Cut release 0.5.1

* Move to smart pointers and split out ParsedText class

* Cleanup ParsedText

* Fix clearCache functions and clear section cache if page load fails

* Bump Page and Section file versions

* Combine removeDir implementations in Epub

* Adjust screen margins

.clangd

@@ -0,0 +1,2 @@
+CompileFlags:
+    Add: [-std=c++2a]

README.md

@@ -36,7 +36,34 @@ This project is **not affiliated with Xteink**; it's built as a community projec
 - [ ] WiFi connectivity
 - [ ] BLE connectivity
 
-## Getting Started
+## Installing
+
+### Web (latest firmware)
+
+1. Connect your Xteink X4 to your computer via USB-C
+2. Go to https://xteink.dve.al/ and click "Flash CrossPoint firmware"
+
+To revert back to the official firmware, you can flash the latest official firmware from https://xteink.dve.al/, or swap
+back to the other partition using the "Swap boot partition" button here https://xteink.dve.al/debug.
+
+### Web (specific firmware version)
+
+1. Connect your Xteink X4 to your computer via USB-C
+2. Download the `firmware.bin` file from the release of your choice via the [releases page](https://github.com/daveallie/crosspoint-reader/releases)
+3. Go to https://xteink.dve.al/ and flash the firmware file using the "OTA fast flash controls" section
+
+To revert back to the official firmware, you can flash the latest official firmware from https://xteink.dve.al/, or swap
+back to the other partition using the "Swap boot partition" button here https://xteink.dve.al/debug.
+
+### Manual
+
+See [Development](#development) below.
+
+## Usage
+
+See [the user guide](./USER_GUIDE.md) for instructions on operating CrossPoint.
+
+## Development
 
 ### Prerequisites
 
@@ -58,24 +85,12 @@ git submodule update --init --recursive
 
 ### Flashing your device
 
-#### Command line
-
 Connect your Xteink X4 to your computer via USB-C and run the following command.
 
 ```sh
 pio run --target upload
 ```
 
-#### Web
-
-1. Connect your Xteink X4 to your computer via USB-C
-2. Download the `firmware.bin` file from the latest release via the [releases page](https://github.com/daveallie/crosspoint-reader/releases)
-3. Go to https://xteink.dve.al/ and flash the firmware file using the "OTA fast flash controls" section
-4. Press the reset button on the Xteink X4 to restart the device
-
-To revert back to the official firmware, you can flash the latest official firmware from https://xteink.dve.al/, or swap
-back to the other partition using the "Swap boot partition" button here https://xteink.dve.al/debug. 
-
 ## Internals
 
 CrossPoint Reader is pretty aggressive about caching data down to the SD card to minimise RAM usage. The ESP32-C3 only

USER_GUIDE.md

@@ -0,0 +1,78 @@
+# CrossPoint User Guide
+
+Welcome to the **CrossPoint** firmware. This guide outlines the hardware controls, navigation, and reading features of 
+the device.
+
+## 1. Hardware Overview
+
+The device utilises the standard buttons on the Xtink X4 in the same layout:
+
+### Button Layout
+| Location        | Buttons                                    |
+|-----------------|--------------------------------------------|
+| **Bottom Edge** | **Back**, **Confirm**, **Left**, **Right** |
+| **Right Side**  | **Power**, **Volume Up**, **Volume Down**  |
+
+---
+
+## 2. Power & Startup
+
+### Power On / Off
+
+To turn the device on or off, **press and hold the Power button for 1 full second**.
+
+### First Launch
+
+Upon turning the device on for the first time, you will be placed on the **Book Selection Screen** (File Browser).
+
+> **Note:** On subsequent restarts, the firmware will automatically reopen the last book you were reading.
+
+---
+
+## 3. Book Selection
+
+The Home Screen acts as a folder and file browser.
+
+* **Navigate List:** Use **Left** (or **Volume Up**), or **Right** (or **Volume Down**) to move the selection cursor up 
+  and down through folders and books.
+* **Open Selection:** Press **Confirm** to open a folder or read a selected book.
+
+---
+
+## 4. Reading Mode
+
+Once you have opened a book, the button layout changes to facilitate reading.
+
+### Page Turning
+| Action            | Buttons                              |
+|-------------------|--------------------------------------|
+| **Previous Page** | Press **Left** _or_ **Volume Up**    |
+| **Next Page**     | Press **Right** _or_ **Volume Down** |
+
+### Chapter Navigation
+* **Next Chapter:** Press and **hold** the **Right** (or **Volume Down**) button briefly, then release.
+* **Previous Chapter:** Press and **hold** the **Left** (or **Volume Up**) button briefly, then release.
+
+### System Navigation
+* **Return to Home:** Press **Back** to close the book and return to the Book Selection screen.
+* **Chapter Menu:** Press **Confirm** to open the Table of Contents/Chapter Selection screen.
+
+---
+
+## 5. Chapter Selection Screen
+
+Accessible by pressing **Confirm** while inside a book.
+
+1.  Use **Left** (or **Volume Up**), or **Right** (or **Volume Down**) to highlight the desired chapter.
+2.  Press **Confirm** to jump to that chapter.
+3.  *Alternatively, press **Back** to cancel and return to your current page.*
+
+---
+
+## 6. Current Limitations & Roadmap
+
+Please note that this firmware is currently in active development. The following features are **not yet supported** but
+are planned for future updates:
+
+* **Images:** Embedded images in e-books will not render.
+* **Text Formatting:** There are currently no settings to adjust font type, size, line spacing, or margins.

lib/EpdFont/EpdFontData.h

@@ -31,4 +31,5 @@ typedef struct {
   uint8_t advanceY;                     ///< Newline distance (y axis)
   int ascender;                         ///< Maximal height of a glyph above the base line
   int descender;                        ///< Maximal height of a glyph below the base line
+  bool is2Bit;
 } EpdFontData;

lib/EpdFont/builtinFonts/babyblue.h

@@ -2,6 +2,7 @@
  * generated by fontconvert.py
  * name: babyblue
  * size: 8
+ * mode: 1-bit
  */
 #pragma once
 #include "EpdFontData.h"
@@ -500,5 +501,5 @@ static const EpdUnicodeInterval babyblueIntervals[] = {
 };
 
 static const EpdFontData babyblue = {
-    babyblueBitmaps, babyblueGlyphs, babyblueIntervals, 5, 17, 13, -4,
+    babyblueBitmaps, babyblueGlyphs, babyblueIntervals, 5, 17, 13, -4, false,
 };

lib/EpdFont/builtinFonts/pixelarial14.h

@@ -0,0 +1,184 @@
+/**
+ * generated by fontconvert.py
+ * name: pixelarial14
+ * size: 8
+ * mode: 1-bit
+ */
+#pragma once
+#include "EpdFontData.h"
+
+static const uint8_t pixelarial14Bitmaps[1145] = {
+    0xFF, 0xFF, 0xFF, 0xC0, 0xFF, 0xFF, 0xFF, 0x1C, 0x63, 0x8C, 0xF7, 0x98, 0xCF, 0xFF, 0xFF, 0xDC, 0xE7, 0xFE, 0xFF,
+    0xFF, 0xFB, 0x9C, 0x63, 0x0C, 0x60, 0x30, 0xF3, 0xFF, 0xBF, 0x1F, 0x9F, 0x9B, 0x37, 0xEF, 0xFB, 0xE3, 0x00, 0x70,
+    0x67, 0xCF, 0x37, 0x61, 0xBB, 0x0D, 0xF0, 0x7D, 0x81, 0xDD, 0xC0, 0xDF, 0x07, 0x98, 0xFC, 0xC7, 0x66, 0x7B, 0xF3,
+    0x07, 0x00, 0x3E, 0x0F, 0xE1, 0x8C, 0x31, 0x86, 0x60, 0xFC, 0x1F, 0x07, 0xE4, 0xC7, 0x98, 0xF3, 0x0E, 0x7F, 0xF7,
+    0xE6, 0xFF, 0xF0, 0x37, 0x66, 0xCC, 0xCC, 0xCC, 0xCC, 0xC6, 0x67, 0x30, 0xCE, 0x66, 0x33, 0x33, 0x33, 0x33, 0x36,
+    0x6E, 0xC0, 0x6F, 0xF6, 0xFF, 0x08, 0x0E, 0x07, 0x03, 0x8F, 0xFF, 0xFC, 0x70, 0x38, 0x1C, 0x0E, 0x00, 0xFF, 0xC0,
+    0xFB, 0xFF, 0x80, 0xF0, 0x1C, 0x73, 0xCC, 0x30, 0xC7, 0x18, 0x61, 0x8E, 0x30, 0xC0, 0x7E, 0xFF, 0xC3, 0xC3, 0xC3,
+    0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xFF, 0x7E, 0x37, 0xFF, 0x33, 0x33, 0x33, 0x33, 0x30, 0x7E, 0xFF, 0xC3, 0xC3,
+    0x03, 0x03, 0x07, 0x0E, 0x1C, 0x38, 0x70, 0xFF, 0xFF, 0x7E, 0xFF, 0xC3, 0xC3, 0x03, 0x3F, 0x3F, 0x03, 0x03, 0xC3,
+    0xC3, 0xFF, 0x7E, 0x03, 0x03, 0x83, 0xC3, 0xE3, 0x31, 0x99, 0xCD, 0xC6, 0xC3, 0x7F, 0xFF, 0xE0, 0x60, 0x30, 0x7F,
+    0x7F, 0xE0, 0xC0, 0xFE, 0xFF, 0xC3, 0x03, 0x03, 0xC3, 0xC7, 0xFE, 0x7E, 0x7E, 0xFF, 0xC3, 0xC0, 0xC0, 0xFE, 0xFF,
+    0xE3, 0xC3, 0xC3, 0xC3, 0xFF, 0x7E, 0xFF, 0xFF, 0x07, 0x06, 0x06, 0x1E, 0x1C, 0x1C, 0x1C, 0x38, 0x30, 0x30, 0x30,
+    0x7E, 0xFF, 0xC3, 0xC3, 0xC3, 0xFF, 0xFF, 0xC3, 0xC3, 0xC3, 0xC3, 0xFF, 0x7E, 0x7E, 0xFF, 0xC3, 0xC3, 0xC3, 0xC7,
+    0xFF, 0x7F, 0x03, 0x03, 0xC7, 0xFE, 0x7C, 0xF0, 0x00, 0x3C, 0xF0, 0x00, 0x3F, 0xF0, 0x03, 0x03, 0x1E, 0x7E, 0xF0,
+    0xF0, 0x70, 0x7E, 0x1F, 0x03, 0xFF, 0xFF, 0x00, 0xFF, 0xFF, 0xFF, 0xC0, 0xC0, 0x70, 0x7E, 0x1F, 0x0F, 0x1E, 0x7E,
+    0xF0, 0xC0, 0x7E, 0xFF, 0xC3, 0xC3, 0x03, 0x07, 0x1E, 0x1C, 0x30, 0x30, 0x30, 0x30, 0x30, 0x3F, 0x87, 0xFE, 0xFF,
+    0x7D, 0xFB, 0xF1, 0xBF, 0x1B, 0xF3, 0xBF, 0xFF, 0xDF, 0xE6, 0x00, 0x7F, 0x03, 0xF0, 0x06, 0x01, 0xF0, 0x1F, 0x01,
+    0xF0, 0x1F, 0x03, 0xB8, 0x31, 0x87, 0xFC, 0x7F, 0xE7, 0xFE, 0xE0, 0x7C, 0x03, 0xC0, 0x30, 0xFF, 0x7F, 0xF0, 0x78,
+    0x3C, 0x1F, 0xFF, 0xFF, 0x83, 0xC1, 0xE0, 0xF0, 0x7F, 0xFF, 0xF0, 0x3F, 0x0F, 0xF3, 0x87, 0xE0, 0x3C, 0x01, 0x80,
+    0x30, 0x06, 0x00, 0xC0, 0x18, 0x0F, 0x87, 0xBF, 0xC3, 0xF0, 0xFF, 0x1F, 0xF3, 0x07, 0xE0, 0x3C, 0x07, 0x80, 0xF0,
+    0x1E, 0x03, 0xC0, 0x78, 0x0F, 0x07, 0xFF, 0xCF, 0xF0, 0xFF, 0xFF, 0xF0, 0x18, 0x0C, 0x07, 0xFF, 0xFF, 0x80, 0xC0,
+    0x60, 0x30, 0x1F, 0xFF, 0xF8, 0xFF, 0xFF, 0xF0, 0x18, 0x0C, 0x07, 0xFB, 0xFD, 0x80, 0xC0, 0x60, 0x30, 0x18, 0x0C,
+    0x00, 0x3F, 0x87, 0xFE, 0xE0, 0x7C, 0x03, 0xC0, 0x0C, 0x00, 0xC1, 0xFC, 0x1F, 0xC0, 0x3C, 0x03, 0xE0, 0x77, 0xFE,
+    0x3F, 0x80, 0xC1, 0xE0, 0xF0, 0x78, 0x3C, 0x1F, 0xFF, 0xFF, 0x83, 0xC1, 0xE0, 0xF0, 0x78, 0x3C, 0x18, 0xFF, 0xFF,
+    0xFF, 0xC0, 0x06, 0x0C, 0x18, 0x30, 0x60, 0xC1, 0x83, 0x07, 0x8F, 0x1F, 0xF7, 0xC0, 0xC0, 0x78, 0x3F, 0x0E, 0x61,
+    0x8C, 0x61, 0xBC, 0x3F, 0x87, 0xB8, 0xE3, 0x1C, 0x63, 0x0E, 0x60, 0xFC, 0x06, 0xC0, 0x60, 0x30, 0x18, 0x0C, 0x06,
+    0x03, 0x01, 0x80, 0xC0, 0x60, 0x30, 0x1F, 0xFF, 0xF8, 0xC0, 0x3E, 0x07, 0xE0, 0x7E, 0x07, 0xF1, 0xBF, 0x1B, 0xFB,
+    0xBD, 0xF3, 0xDF, 0x3D, 0xF3, 0xDF, 0x3C, 0x63, 0xC6, 0x30, 0xC1, 0xF0, 0xFC, 0x7E, 0x3F, 0x1F, 0xEF, 0x77, 0xBB,
+    0xC7, 0xE3, 0xF1, 0xF8, 0x7C, 0x18, 0x3F, 0x87, 0xFE, 0xE0, 0x7C, 0x03, 0xC0, 0x3C, 0x03, 0xC0, 0x3C, 0x03, 0xC0,
+    0x3C, 0x03, 0xE0, 0x77, 0xFE, 0x3F, 0x80, 0xFF, 0x7F, 0xF0, 0x78, 0x3C, 0x1E, 0x0F, 0xFF, 0xFE, 0xC0, 0x60, 0x30,
+    0x18, 0x0C, 0x00, 0x3F, 0x87, 0xFE, 0xE0, 0x7C, 0x03, 0xC0, 0x3C, 0x03, 0xC0, 0x3C, 0x03, 0xC0, 0x3C, 0x37, 0xE3,
+    0xE7, 0xFF, 0x3F, 0x70, 0xFF, 0x9F, 0xFF, 0x01, 0xE0, 0x3C, 0x07, 0x80, 0xFF, 0xFF, 0xFC, 0xC6, 0x18, 0xE3, 0x0E,
+    0x60, 0xFC, 0x06, 0x7F, 0x7F, 0xF0, 0x78, 0x3C, 0x07, 0xE1, 0xFE, 0x0F, 0x01, 0xE0, 0xF0, 0x7F, 0xF7, 0xF0, 0xFF,
+    0xFF, 0xC7, 0x03, 0x81, 0xC0, 0xE0, 0x70, 0x38, 0x1C, 0x0E, 0x07, 0x03, 0x81, 0xC0, 0xC1, 0xE0, 0xF0, 0x78, 0x3C,
+    0x1E, 0x0F, 0x07, 0x83, 0xC1, 0xE0, 0xF8, 0xEF, 0xE3, 0xE0, 0xC0, 0x3C, 0x03, 0xE0, 0x76, 0x06, 0x60, 0x67, 0x1E,
+    0x31, 0x83, 0xB8, 0x1F, 0x01, 0xF0, 0x1F, 0x00, 0x60, 0x06, 0x00, 0xC1, 0x81, 0xE1, 0xF0, 0xF8, 0xD8, 0xEC, 0x6C,
+    0x66, 0x36, 0x33, 0x1B, 0x19, 0xDD, 0xFC, 0x6C, 0x7C, 0x36, 0x3E, 0x1B, 0x1F, 0x0F, 0x8F, 0x03, 0x83, 0x01, 0xC1,
+    0x80, 0xC0, 0x7C, 0x3D, 0x86, 0x30, 0xC3, 0x30, 0x7E, 0x07, 0x80, 0xF8, 0x33, 0x0E, 0x71, 0x86, 0x70, 0xFC, 0x06,
+    0xC0, 0x3E, 0x07, 0x71, 0xE3, 0x18, 0x31, 0x83, 0xF8, 0x1F, 0x00, 0x60, 0x06, 0x00, 0x60, 0x06, 0x00, 0x60, 0x06,
+    0x00, 0xFF, 0xFF, 0xFC, 0x0E, 0x01, 0x80, 0x30, 0x0E, 0x07, 0x80, 0xE0, 0x30, 0x06, 0x01, 0xC0, 0x7F, 0xFF, 0xFE,
+    0xFF, 0x6D, 0xB6, 0xDB, 0x6D, 0xB7, 0xE0, 0xC3, 0x0E, 0x18, 0x61, 0x87, 0x0C, 0x30, 0xC3, 0x87, 0x1C, 0xFD, 0xB6,
+    0xDB, 0x6D, 0xB6, 0xDF, 0xE0, 0x30, 0xF1, 0xF3, 0xE7, 0xDD, 0xF1, 0x80, 0xFF, 0xFF, 0xFC, 0xCE, 0x73, 0x00, 0x7E,
+    0x7E, 0xC3, 0xC3, 0x3F, 0x7F, 0x63, 0xE3, 0xC7, 0xFF, 0x7F, 0xC0, 0xC0, 0xFE, 0xFE, 0xE3, 0xE3, 0xC3, 0xC3, 0xC3,
+    0xC3, 0xE3, 0xFF, 0xFE, 0x78, 0xFB, 0x1E, 0x3C, 0x18, 0x30, 0x60, 0xC7, 0xFD, 0xF0, 0x03, 0x03, 0x7B, 0x7F, 0xC7,
+    0xC7, 0xC3, 0xC3, 0xC3, 0xC3, 0xC7, 0xFF, 0x7F, 0x7E, 0x7E, 0xC3, 0xC3, 0xFF, 0xFF, 0xC0, 0xC0, 0xC3, 0xFF, 0x7E,
+    0x3D, 0xEF, 0xBF, 0x61, 0x86, 0x18, 0x61, 0x86, 0x18, 0x60, 0x7B, 0x7F, 0xC7, 0xC7, 0xC3, 0xC3, 0xC3, 0xC3, 0xC7,
+    0xFF, 0x7F, 0x03, 0xC3, 0xFF, 0x7E, 0xC0, 0xC0, 0xFE, 0xFE, 0xE3, 0xE3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3,
+    0xFF, 0xFF, 0xFF, 0xC0, 0x33, 0x33, 0x33, 0x33, 0x33, 0x33, 0x33, 0x3F, 0xE0, 0xC0, 0xC0, 0xC3, 0xC3, 0xC6, 0xDE,
+    0xFC, 0xF8, 0xFC, 0xEE, 0xC6, 0xC7, 0xC3, 0xFF, 0xFF, 0xFF, 0xC0, 0xF9, 0xEF, 0xDE, 0xE7, 0x3E, 0x73, 0xC6, 0x3C,
+    0x63, 0xC6, 0x3C, 0x63, 0xC6, 0x3C, 0x63, 0xC6, 0x30, 0xFE, 0xFE, 0xE3, 0xE3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3,
+    0xC3, 0x7E, 0x7E, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3, 0xFF, 0x7E, 0xFE, 0xFE, 0xE3, 0xE3, 0xC3, 0xC3, 0xC3,
+    0xC3, 0xE3, 0xFF, 0xFE, 0xC0, 0xC0, 0xC0, 0xC0, 0x7B, 0x7F, 0xC7, 0xC7, 0xC3, 0xC3, 0xC3, 0xC3, 0xC7, 0xFF, 0x7F,
+    0x03, 0x03, 0x03, 0x03, 0xFB, 0xFE, 0x38, 0xC3, 0x0C, 0x30, 0xC3, 0x0C, 0x00, 0x78, 0xFB, 0x1E, 0x3F, 0x8F, 0x81,
+    0x83, 0xC7, 0xFD, 0xF0, 0x61, 0x8F, 0xBF, 0x61, 0x86, 0x18, 0x61, 0x86, 0x1E, 0x7C, 0xC3, 0xC3, 0xC3, 0xC3, 0xC3,
+    0xC3, 0xC3, 0xC3, 0xC7, 0xFF, 0x7F, 0xC1, 0xE0, 0xF0, 0x7C, 0x76, 0x33, 0xB8, 0xD8, 0x6C, 0x3E, 0x0E, 0x07, 0x00,
+    0xC6, 0x3C, 0x63, 0xC6, 0x3F, 0xF7, 0x7F, 0x67, 0xF6, 0x7F, 0x67, 0xF6, 0x7B, 0xE3, 0x18, 0x31, 0x80, 0xC3, 0xC3,
+    0x66, 0x66, 0x7E, 0x3C, 0x3C, 0x7E, 0x66, 0xE7, 0xC3, 0xC1, 0xE0, 0xF0, 0x7C, 0x76, 0x33, 0xB8, 0xD8, 0x6C, 0x36,
+    0x1F, 0x07, 0x03, 0x81, 0xC3, 0xE1, 0xC0, 0xFF, 0xFF, 0x06, 0x1E, 0x1C, 0x1C, 0x30, 0x30, 0x70, 0xFF, 0xFF, 0x37,
+    0x66, 0x66, 0x6E, 0xCE, 0x66, 0x66, 0x67, 0x30, 0xFF, 0xFF, 0xFF, 0xC0, 0xCE, 0x66, 0x66, 0x67, 0x37, 0x66, 0x66,
+    0x6E, 0xC0, 0xC3, 0x9B, 0xFF, 0xF9, 0xB8, 0x30, 0xDB, 0x66, 0xC0, 0x6D, 0xBD, 0x80, 0x7F, 0xEF, 0x3C, 0xF3, 0xC0,
+    0x7D, 0xF7, 0xDF, 0xF3, 0xC0,
+};
+
+static const EpdGlyph pixelarial14Glyphs[] = {
+    {0, 0, 4, 0, 0, 0, 0},          //
+    {2, 13, 3, 0, 13, 4, 0},        // !
+    {4, 6, 5, 0, 13, 3, 4},         // "
+    {11, 13, 12, 0, 13, 18, 7},     // #
+    {7, 13, 8, 0, 13, 12, 25},      // $
+    {13, 13, 14, 0, 13, 22, 37},    // %
+    {11, 13, 12, 0, 13, 18, 59},    // &
+    {2, 6, 3, 0, 13, 2, 77},        // '
+    {4, 17, 5, 0, 13, 9, 79},       // (
+    {4, 17, 5, 0, 13, 9, 88},       // )
+    {4, 6, 5, 0, 13, 3, 97},        // *
+    {9, 10, 10, 0, 11, 12, 100},    // +
+    {2, 5, 3, 0, 2, 2, 112},        // ,
+    {6, 3, 6, 0, 6, 3, 114},        // -
+    {2, 2, 3, 0, 2, 1, 117},        // .
+    {6, 13, 6, 0, 13, 10, 118},     // /
+    {8, 13, 9, 0, 13, 13, 128},     // 0
+    {4, 13, 5, 0, 13, 7, 141},      // 1
+    {8, 13, 9, 0, 13, 13, 148},     // 2
+    {8, 13, 9, 0, 13, 13, 161},     // 3
+    {9, 13, 10, 0, 13, 15, 174},    // 4
+    {8, 13, 9, 0, 13, 13, 189},     // 5
+    {8, 13, 9, 0, 13, 13, 202},     // 6
+    {8, 13, 9, 0, 13, 13, 215},     // 7
+    {8, 13, 9, 0, 13, 13, 228},     // 8
+    {8, 13, 9, 0, 13, 13, 241},     // 9
+    {2, 11, 3, 0, 11, 3, 254},      // :
+    {2, 14, 3, 0, 11, 4, 257},      // ;
+    {8, 10, 9, 0, 11, 10, 261},     // <
+    {8, 6, 9, 0, 9, 6, 271},        // =
+    {8, 10, 9, 0, 11, 10, 277},     // >
+    {8, 13, 9, 0, 13, 13, 287},     // ?
+    {12, 12, 13, 0, 9, 18, 300},    // @
+    {12, 13, 13, 0, 13, 20, 318},   // A
+    {9, 13, 10, 0, 13, 15, 338},    // B
+    {11, 13, 12, 0, 13, 18, 353},   // C
+    {11, 13, 12, 0, 13, 18, 371},   // D
+    {9, 13, 10, 0, 13, 15, 389},    // E
+    {9, 13, 10, 0, 13, 15, 404},    // F
+    {12, 13, 13, 0, 13, 20, 419},   // G
+    {9, 13, 10, 0, 13, 15, 439},    // H
+    {2, 13, 3, 0, 13, 4, 454},      // I
+    {7, 13, 8, 0, 13, 12, 458},     // J
+    {11, 13, 12, 0, 13, 18, 470},   // K
+    {9, 13, 10, 0, 13, 15, 488},    // L
+    {12, 13, 13, 0, 13, 20, 503},   // M
+    {9, 13, 10, 0, 13, 15, 523},    // N
+    {12, 13, 13, 0, 13, 20, 538},   // O
+    {9, 13, 10, 0, 13, 15, 558},    // P
+    {12, 13, 13, 0, 13, 20, 573},   // Q
+    {11, 13, 12, 0, 13, 18, 593},   // R
+    {9, 13, 10, 0, 13, 15, 611},    // S
+    {9, 13, 10, 0, 13, 15, 626},    // T
+    {9, 13, 10, 0, 13, 15, 641},    // U
+    {12, 13, 13, 0, 13, 20, 656},   // V
+    {17, 13, 18, 0, 13, 28, 676},   // W
+    {11, 13, 12, 0, 13, 18, 704},   // X
+    {12, 13, 13, 0, 13, 20, 722},   // Y
+    {11, 13, 12, 0, 13, 18, 742},   // Z
+    {3, 17, 4, 0, 13, 7, 760},      // [
+    {6, 13, 6, 0, 13, 10, 767},     // <backslash>
+    {3, 17, 4, 0, 13, 7, 777},      // ]
+    {7, 7, 8, 0, 13, 7, 784},       // ^
+    {11, 2, 12, 0, 2, 3, 791},      // _
+    {4, 5, 5, 0, 13, 3, 794},       // `
+    {8, 11, 9, 0, 11, 11, 797},     // a
+    {8, 13, 9, 0, 13, 13, 808},     // b
+    {7, 11, 8, 0, 11, 10, 821},     // c
+    {8, 13, 9, 0, 13, 13, 831},     // d
+    {8, 11, 9, 0, 11, 11, 844},     // e
+    {6, 13, 6, 0, 13, 10, 855},     // f
+    {8, 15, 9, 0, 11, 15, 865},     // g
+    {8, 13, 9, 0, 13, 13, 880},     // h
+    {2, 13, 3, 0, 13, 4, 893},      // i
+    {4, 17, 5, 0, 13, 9, 897},      // j
+    {8, 13, 9, 0, 13, 13, 906},     // k
+    {2, 13, 3, 0, 13, 4, 919},      // l
+    {12, 11, 13, 0, 11, 17, 923},   // m
+    {8, 11, 9, 0, 11, 11, 940},     // n
+    {8, 11, 9, 0, 11, 11, 951},     // o
+    {8, 15, 9, 0, 11, 15, 962},     // p
+    {8, 15, 9, 0, 11, 15, 977},     // q
+    {6, 11, 6, 0, 11, 9, 992},      // r
+    {7, 11, 8, 0, 11, 10, 1001},    // s
+    {6, 13, 6, 0, 13, 10, 1011},    // t
+    {8, 11, 9, 0, 11, 11, 1021},    // u
+    {9, 11, 10, 0, 11, 13, 1032},   // v
+    {12, 11, 13, 0, 11, 17, 1045},  // w
+    {8, 11, 9, 0, 11, 11, 1062},    // x
+    {9, 15, 10, 0, 11, 17, 1073},   // y
+    {8, 11, 9, 0, 11, 11, 1090},    // z
+    {4, 17, 5, 0, 13, 9, 1101},     // {
+    {2, 13, 3, 0, 13, 4, 1110},     // |
+    {4, 17, 5, 0, 13, 9, 1114},     // }
+    {11, 4, 12, 0, 9, 6, 1123},     // ~
+    {3, 6, 4, 0, 13, 3, 1129},      // ‘
+    {3, 6, 4, 0, 13, 3, 1132},      // ’
+    {6, 6, 6, 0, 13, 5, 1135},      // “
+    {6, 6, 6, 0, 13, 5, 1140},      // ”
+};
+
+static const EpdUnicodeInterval pixelarial14Intervals[] = {
+    {0x20, 0x7E, 0x0},
+    {0x2018, 0x2019, 0x5F},
+    {0x201C, 0x201D, 0x61},
+};
+
+static const EpdFontData pixelarial14 = {
+    pixelarial14Bitmaps, pixelarial14Glyphs, pixelarial14Intervals, 3, 17, 13, -4, false,
+};

lib/EpdFont/builtinFonts/ubuntu_10.h

@@ -2,6 +2,7 @@
  * generated by fontconvert.py
  * name: ubuntu_10
  * size: 10
+ * mode: 1-bit
  */
 #pragma once
 #include "EpdFontData.h"
@@ -762,5 +763,5 @@ static const EpdUnicodeInterval ubuntu_10Intervals[] = {
 };
 
 static const EpdFontData ubuntu_10 = {
-    ubuntu_10Bitmaps, ubuntu_10Glyphs, ubuntu_10Intervals, 31, 24, 20, -4,
+    ubuntu_10Bitmaps, ubuntu_10Glyphs, ubuntu_10Intervals, 31, 24, 20, -4, false,
 };

lib/EpdFont/builtinFonts/ubuntu_bold_10.h

@@ -2,6 +2,7 @@
  * generated by fontconvert.py
  * name: ubuntu_bold_10
  * size: 10
+ * mode: 1-bit
  */
 #pragma once
 #include "EpdFontData.h"
@@ -806,5 +807,5 @@ static const EpdUnicodeInterval ubuntu_bold_10Intervals[] = {
 };
 
 static const EpdFontData ubuntu_bold_10 = {
-    ubuntu_bold_10Bitmaps, ubuntu_bold_10Glyphs, ubuntu_bold_10Intervals, 31, 24, 20, -4,
+    ubuntu_bold_10Bitmaps, ubuntu_bold_10Glyphs, ubuntu_bold_10Intervals, 31, 24, 20, -4, false,
 };

lib/EpdFont/scripts/fontconvert.py

@@ -13,12 +13,14 @@ parser = argparse.ArgumentParser(description="Generate a header file from a font
 parser.add_argument("name", action="store", help="name of the font.")
 parser.add_argument("size", type=int, help="font size to use.")
 parser.add_argument("fontstack", action="store", nargs='+', help="list of font files, ordered by descending priority.")
+parser.add_argument("--2bit", dest="is2Bit", action="store_true", help="generate 2-bit greyscale bitmap instead of 1-bit black and white.")
 parser.add_argument("--additional-intervals", dest="additional_intervals", action="append", help="Additional code point intervals to export as min,max. This argument can be repeated.")
 args = parser.parse_args()
 
 GlyphProps = namedtuple("GlyphProps", ["width", "height", "advance_x", "left", "top", "data_length", "data_offset", "code_point"])
 
 font_stack = [freetype.Face(f) for f in args.fontstack]
+is2Bit = args.is2Bit
 size = args.size
 font_name = args.name
 
@@ -173,26 +175,73 @@ for i_start, i_end in intervals:
                 pixels4g.append(px)
                 px = 0
 
-        # Downsample to 1-bit bitmap - treat any non-zero as black
+        if is2Bit:
-        pixelsbw = []
+            # 0 = white, 15 black, 8+ dark grey, 7- light grey
-        px = 0
+            # Downsample to 2-bit bitmap
-        pitch = (bitmap.width // 2) + (bitmap.width % 2)
+            pixels2b = []
-        for y in range(bitmap.rows):
+            px = 0
-            for x in range(bitmap.width):
+            pitch = (bitmap.width // 2) + (bitmap.width % 2)
-                px = px << 1
+            for y in range(bitmap.rows):
-                bm = pixels4g[y * pitch + (x // 2)]
+                for x in range(bitmap.width):
-                px += 1 if ((x & 1) == 0 and bm & 0xF > 0) or ((x & 1) == 1 and bm & 0xF0 > 0) else 0
+                    px = px << 2
+                    bm = pixels4g[y * pitch + (x // 2)]
+                    bm = (bm >> ((x % 2) * 4)) & 0xF
 
-                if (y * bitmap.width + x) % 8 == 7:
+                    if bm == 15:
-                    pixelsbw.append(px)
+                        px += 3
-                    px = 0
+                    elif bm >= 8:
-        if (bitmap.width * bitmap.rows) % 8 != 0:
+                        px += 2
-            px = px << (8 - (bitmap.width * bitmap.rows) % 8)
+                    elif bm > 0:
-            pixelsbw.append(px)
+                        px += 1
 
+                    if (y * bitmap.width + x) % 4 == 3:
+                        pixels2b.append(px)
+                        px = 0
+            if (bitmap.width * bitmap.rows) % 4 != 0:
+                px = px << (4 - (bitmap.width * bitmap.rows) % 4) * 2
+                pixels2b.append(px)
+
+            # for y in range(bitmap.rows):
+            #     line = ''
+            #     for x in range(bitmap.width):
+            #         pixelPosition = y * bitmap.width + x
+            #         byte = pixels2b[pixelPosition // 4]
+            #         bit_index = (3 - (pixelPosition % 4)) * 2
+            #         line += '#' if ((byte >> bit_index) & 3) > 0 else '.'
+            #     print(line)
+            # print('')
+        else:
+            # Downsample to 1-bit bitmap - treat any non-zero as black
+            pixelsbw = []
+            px = 0
+            pitch = (bitmap.width // 2) + (bitmap.width % 2)
+            for y in range(bitmap.rows):
+                for x in range(bitmap.width):
+                    px = px << 1
+                    bm = pixels4g[y * pitch + (x // 2)]
+                    px += 1 if ((x & 1) == 0 and bm & 0xF > 0) or ((x & 1) == 1 and bm & 0xF0 > 0) else 0
+
+                    if (y * bitmap.width + x) % 8 == 7:
+                        pixelsbw.append(px)
+                        px = 0
+            if (bitmap.width * bitmap.rows) % 8 != 0:
+                px = px << (8 - (bitmap.width * bitmap.rows) % 8)
+                pixelsbw.append(px)
+
+            # for y in range(bitmap.rows):
+            #     line = ''
+            #     for x in range(bitmap.width):
+            #         pixelPosition = y * bitmap.width + x
+            #         byte = pixelsbw[pixelPosition // 8]
+            #         bit_index = 7 - (pixelPosition % 8)
+            #         line += '#' if (byte >> bit_index) & 1 else '.'
+            #     print(line)
+            # print('')
+
+        pixels = pixels2b if is2Bit else pixelsbw
 
         # Build output data
-        packed = bytes(pixelsbw)
+        packed = bytes(pixels)
         glyph = GlyphProps(
             width = bitmap.width,
             height = bitmap.rows,
@@ -216,7 +265,7 @@ for index, glyph in enumerate(all_glyphs):
     glyph_data.extend([b for b in packed])
     glyph_props.append(props)
 
-print(f"/**\n * generated by fontconvert.py\n * name: {font_name}\n * size: {size}\n */")
+print(f"/**\n * generated by fontconvert.py\n * name: {font_name}\n * size: {size}\n * mode: {'2-bit' if is2Bit else '1-bit'}\n */")
 print("#pragma once")
 print("#include \"EpdFontData.h\"\n")
 print(f"static const uint8_t {font_name}Bitmaps[{len(glyph_data)}] = {{")
@@ -244,4 +293,5 @@ print(f"    {len(intervals)},")
 print(f"    {norm_ceil(face.size.height)},")
 print(f"    {norm_ceil(face.size.ascender)},")
 print(f"    {norm_floor(face.size.descender)},")
+print(f"    {'true' if is2Bit else 'false'},")
 print("};")

lib/EpdFontRenderer/EpdFontRenderer.hpp

@@ -1,84 +0,0 @@
-#pragma once
-#include <EpdFontFamily.h>
-#include <HardwareSerial.h>
-#include <Utf8.h>
-
-inline int min(const int a, const int b) { return a < b ? a : b; }
-inline int max(const int a, const int b) { return a > b ? a : b; }
-
-template <typename Renderable>
-class EpdFontRenderer {
-  Renderable& renderer;
-  void renderChar(uint32_t cp, int* x, const int* y, uint16_t color, EpdFontStyle style = REGULAR);
-
- public:
-  const EpdFontFamily* fontFamily;
-  explicit EpdFontRenderer(const EpdFontFamily* fontFamily, Renderable& renderer)
-      : fontFamily(fontFamily), renderer(renderer) {}
-  ~EpdFontRenderer() = default;
-  void renderString(const char* string, int* x, int* y, uint16_t color, EpdFontStyle style = REGULAR);
-};
-
-template <typename Renderable>
-void EpdFontRenderer<Renderable>::renderString(const char* string, int* x, int* y, const uint16_t color,
-                                               const EpdFontStyle style) {
-  // cannot draw a NULL / empty string
-  if (string == nullptr || *string == '\0') {
-    return;
-  }
-
-  // no printable characters
-  if (!fontFamily->hasPrintableChars(string, style)) {
-    return;
-  }
-
-  uint32_t cp;
-  while ((cp = utf8NextCodepoint(reinterpret_cast<const uint8_t**>(&string)))) {
-    renderChar(cp, x, y, color, style);
-  }
-
-  *y += fontFamily->getData(style)->advanceY;
-}
-
-template <typename Renderable>
-void EpdFontRenderer<Renderable>::renderChar(const uint32_t cp, int* x, const int* y, uint16_t color,
-                                             const EpdFontStyle style) {
-  const EpdGlyph* glyph = fontFamily->getGlyph(cp, style);
-  if (!glyph) {
-    // TODO: Replace with fallback glyph property?
-    glyph = fontFamily->getGlyph('?', style);
-  }
-
-  // no glyph?
-  if (!glyph) {
-    Serial.printf("No glyph for codepoint %d\n", cp);
-    return;
-  }
-
-  const uint32_t offset = glyph->dataOffset;
-  const uint8_t width = glyph->width;
-  const uint8_t height = glyph->height;
-  const int left = glyph->left;
-
-  const uint8_t* bitmap = nullptr;
-  bitmap = &fontFamily->getData(style)->bitmap[offset];
-
-  if (bitmap != nullptr) {
-    for (int glyphY = 0; glyphY < height; glyphY++) {
-      int screenY = *y - glyph->top + glyphY;
-      for (int glyphX = 0; glyphX < width; glyphX++) {
-        const int pixelPosition = glyphY * width + glyphX;
-        int screenX = *x + left + glyphX;
-
-        const uint8_t byte = bitmap[pixelPosition / 8];
-        const uint8_t bit_index = 7 - (pixelPosition % 8);
-
-        if ((byte >> bit_index) & 1) {
-          renderer.drawPixel(screenX, screenY, color);
-        }
-      }
-    }
-  }
-
-  *x += glyph->advanceX;
-}

lib/EpdRenderer/EpdRenderer.cpp

@@ -1,168 +0,0 @@
-#include "EpdRenderer.h"
-
-#include "builtinFonts/babyblue.h"
-#include "builtinFonts/bookerly.h"
-#include "builtinFonts/bookerly_bold.h"
-#include "builtinFonts/bookerly_bold_italic.h"
-#include "builtinFonts/bookerly_italic.h"
-#include "builtinFonts/ubuntu_10.h"
-#include "builtinFonts/ubuntu_bold_10.h"
-
-EpdFont bookerlyFont(&bookerly);
-EpdFont bookerlyBoldFont(&bookerly_bold);
-EpdFont bookerlyItalicFont(&bookerly_italic);
-EpdFont bookerlyBoldItalicFont(&bookerly_bold_italic);
-EpdFontFamily bookerlyFontFamily(&bookerlyFont, &bookerlyBoldFont, &bookerlyItalicFont, &bookerlyBoldItalicFont);
-
-EpdFont smallFont(&babyblue);
-EpdFontFamily smallFontFamily(&smallFont);
-
-EpdFont ubuntu10Font(&ubuntu_10);
-EpdFont ununtuBold10Font(&ubuntu_bold_10);
-EpdFontFamily ubuntuFontFamily(&ubuntu10Font, &ununtuBold10Font);
-
-EpdRenderer::EpdRenderer(XteinkDisplay& display)
-    : display(display), marginTop(11), marginBottom(30), marginLeft(10), marginRight(10), lineCompression(0.95f) {
-  this->regularFontRenderer = new EpdFontRenderer<XteinkDisplay>(&bookerlyFontFamily, display);
-  this->smallFontRenderer = new EpdFontRenderer<XteinkDisplay>(&smallFontFamily, display);
-  this->uiFontRenderer = new EpdFontRenderer<XteinkDisplay>(&ubuntuFontFamily, display);
-}
-
-EpdRenderer::~EpdRenderer() {
-  delete regularFontRenderer;
-  delete smallFontRenderer;
-  delete uiFontRenderer;
-}
-
-int EpdRenderer::getTextWidth(const char* text, const EpdFontStyle style) const {
-  int w = 0, h = 0;
-
-  regularFontRenderer->fontFamily->getTextDimensions(text, &w, &h, style);
-
-  return w;
-}
-
-int EpdRenderer::getUiTextWidth(const char* text, const EpdFontStyle style) const {
-  int w = 0, h = 0;
-
-  uiFontRenderer->fontFamily->getTextDimensions(text, &w, &h, style);
-
-  return w;
-}
-
-int EpdRenderer::getSmallTextWidth(const char* text, const EpdFontStyle style) const {
-  int w = 0, h = 0;
-
-  smallFontRenderer->fontFamily->getTextDimensions(text, &w, &h, style);
-
-  return w;
-}
-
-void EpdRenderer::drawText(const int x, const int y, const char* text, const uint16_t color,
-                           const EpdFontStyle style) const {
-  int ypos = y + getLineHeight() + marginTop;
-  int xpos = x + marginLeft;
-  regularFontRenderer->renderString(text, &xpos, &ypos, color > 0 ? GxEPD_BLACK : GxEPD_WHITE, style);
-}
-
-void EpdRenderer::drawUiText(const int x, const int y, const char* text, const uint16_t color,
-                             const EpdFontStyle style) const {
-  int ypos = y + uiFontRenderer->fontFamily->getData(style)->advanceY + marginTop;
-  int xpos = x + marginLeft;
-  uiFontRenderer->renderString(text, &xpos, &ypos, color > 0 ? GxEPD_BLACK : GxEPD_WHITE, style);
-}
-
-void EpdRenderer::drawSmallText(const int x, const int y, const char* text, const uint16_t color,
-                                const EpdFontStyle style) const {
-  int ypos = y + smallFontRenderer->fontFamily->getData(style)->advanceY + marginTop;
-  int xpos = x + marginLeft;
-  smallFontRenderer->renderString(text, &xpos, &ypos, color > 0 ? GxEPD_BLACK : GxEPD_WHITE, style);
-}
-
-void EpdRenderer::drawTextBox(const int x, const int y, const std::string& text, const int width, const int height,
-                              const EpdFontStyle style) const {
-  const size_t length = text.length();
-  // fit the text into the box
-  int start = 0;
-  int end = 1;
-  int ypos = 0;
-  while (true) {
-    if (end >= length) {
-      drawText(x, y + ypos, text.substr(start, length - start).c_str(), 1, style);
-      break;
-    }
-
-    if (ypos + getLineHeight() >= height) {
-      break;
-    }
-
-    if (text[end - 1] == '\n') {
-      drawText(x, y + ypos, text.substr(start, end - start).c_str(), 1, style);
-      ypos += getLineHeight();
-      start = end;
-      end = start + 1;
-      continue;
-    }
-
-    if (getTextWidth(text.substr(start, end - start).c_str(), style) > width) {
-      drawText(x, y + ypos, text.substr(start, end - start - 1).c_str(), 1, style);
-      ypos += getLineHeight();
-      start = end - 1;
-      continue;
-    }
-
-    end++;
-  }
-}
-
-void EpdRenderer::drawLine(int x1, int y1, int x2, int y2, uint16_t color) const {
-  display.drawLine(x1 + marginLeft, y1 + marginTop, x2 + marginLeft, y2 + marginTop,
-                   color > 0 ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::drawRect(const int x, const int y, const int width, const int height, const uint16_t color) const {
-  display.drawRect(x + marginLeft, y + marginTop, width, height, color > 0 ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::fillRect(const int x, const int y, const int width, const int height, const uint16_t color) const {
-  display.fillRect(x + marginLeft, y + marginTop, width, height, color > 0 ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::drawCircle(const int x, const int y, const int radius, const uint16_t color) const {
-  display.drawCircle(x + marginLeft, y + marginTop, radius, color > 0 ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::fillCircle(const int x, const int y, const int radius, const uint16_t color) const {
-  display.fillCircle(x + marginLeft, y + marginTop, radius, color > 0 ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::drawImage(const uint8_t bitmap[], const int x, const int y, const int width, const int height,
-                            const bool invert, const bool mirrorY) const {
-  drawImageNoMargin(bitmap, x + marginLeft, y + marginTop, width, height, invert, mirrorY);
-}
-
-void EpdRenderer::drawImageNoMargin(const uint8_t bitmap[], const int x, const int y, const int width, const int height,
-                                    const bool invert, const bool mirrorY) const {
-  display.drawImage(bitmap, x, y, width, height, invert, mirrorY);
-}
-
-void EpdRenderer::clearScreen(const bool black) const {
-  Serial.println("Clearing screen");
-  display.fillScreen(black ? GxEPD_BLACK : GxEPD_WHITE);
-}
-
-void EpdRenderer::flushDisplay(const bool partialUpdate) const { display.display(partialUpdate); }
-
-void EpdRenderer::flushArea(const int x, const int y, const int width, const int height) const {
-  display.displayWindow(x + marginLeft, y + marginTop, width, height);
-}
-
-int EpdRenderer::getPageWidth() const { return display.width() - marginLeft - marginRight; }
-
-int EpdRenderer::getPageHeight() const { return display.height() - marginTop - marginBottom; }
-
-int EpdRenderer::getSpaceWidth() const { return regularFontRenderer->fontFamily->getGlyph(' ', REGULAR)->advanceX; }
-
-int EpdRenderer::getLineHeight() const {
-  return regularFontRenderer->fontFamily->getData(REGULAR)->advanceY * lineCompression;
-}

lib/EpdRenderer/EpdRenderer.h

@@ -1,52 +0,0 @@
-#pragma once
-
-#include <GxEPD2_BW.h>
-
-#include <EpdFontRenderer.hpp>
-
-#define XteinkDisplay GxEPD2_BW<GxEPD2_426_GDEQ0426T82, GxEPD2_426_GDEQ0426T82::HEIGHT>
-
-class EpdRenderer {
-  XteinkDisplay& display;
-  EpdFontRenderer<XteinkDisplay>* regularFontRenderer;
-  EpdFontRenderer<XteinkDisplay>* smallFontRenderer;
-  EpdFontRenderer<XteinkDisplay>* uiFontRenderer;
-  int marginTop;
-  int marginBottom;
-  int marginLeft;
-  int marginRight;
-  float lineCompression;
-
- public:
-  explicit EpdRenderer(XteinkDisplay& display);
-  ~EpdRenderer();
-  int getTextWidth(const char* text, EpdFontStyle style = REGULAR) const;
-  int getUiTextWidth(const char* text, EpdFontStyle style = REGULAR) const;
-  int getSmallTextWidth(const char* text, EpdFontStyle style = REGULAR) const;
-  void drawText(int x, int y, const char* text, uint16_t color = 1, EpdFontStyle style = REGULAR) const;
-  void drawUiText(int x, int y, const char* text, uint16_t color = 1, EpdFontStyle style = REGULAR) const;
-  void drawSmallText(int x, int y, const char* text, uint16_t color = 1, EpdFontStyle style = REGULAR) const;
-  void drawTextBox(int x, int y, const std::string& text, int width, int height, EpdFontStyle style = REGULAR) const;
-  void drawLine(int x1, int y1, int x2, int y2, uint16_t color = 1) const;
-  void drawRect(int x, int y, int width, int height, uint16_t color = 1) const;
-  void fillRect(int x, int y, int width, int height, uint16_t color = 1) const;
-  void drawCircle(int x, int y, int radius, uint16_t color = 1) const;
-  void fillCircle(int x, int y, int radius, uint16_t color = 1) const;
-  void drawImage(const uint8_t bitmap[], int x, int y, int width, int height, bool invert = false,
-                 bool mirrorY = false) const;
-  void drawImageNoMargin(const uint8_t bitmap[], int x, int y, int width, int height, bool invert = false,
-                         bool mirrorY = false) const;
-  void clearScreen(bool black = false) const;
-  void flushDisplay(bool partialUpdate = true) const;
-  void flushArea(int x, int y, int width, int height) const;
-
-  int getPageWidth() const;
-  int getPageHeight() const;
-  int getSpaceWidth() const;
-  int getLineHeight() const;
-  // set margins
-  void setMarginTop(const int newMarginTop) { this->marginTop = newMarginTop; }
-  void setMarginBottom(const int newMarginBottom) { this->marginBottom = newMarginBottom; }
-  void setMarginLeft(const int newMarginLeft) { this->marginLeft = newMarginLeft; }
-  void setMarginRight(const int newMarginRight) { this->marginRight = newMarginRight; }
-};

lib/Epub/Epub.cpp

@@ -6,249 +6,166 @@
 
 #include <map>
 
-bool Epub::findContentOpfFile(const ZipFile& zip, std::string& contentOpfFile) {
+#include "Epub/FsHelpers.h"
-  // open up the meta data to find where the content.opf file lives
+#include "Epub/parsers/ContainerParser.h"
-  size_t s;
+#include "Epub/parsers/ContentOpfParser.h"
-  const auto metaInfo = reinterpret_cast<char*>(zip.readFileToMemory("META-INF/container.xml", &s, true));
+#include "Epub/parsers/TocNcxParser.h"
-  if (!metaInfo) {
+
-    Serial.println("Could not find META-INF/container.xml");
+bool Epub::findContentOpfFile(std::string* contentOpfFile) const {
+  const auto containerPath = "META-INF/container.xml";
+  size_t containerSize;
+
+  // Get file size without loading it all into heap
+  if (!getItemSize(containerPath, &containerSize)) {
+    Serial.printf("[%lu] [EBP] Could not find or size META-INF/container.xml\n", millis());
     return false;
   }
 
-  // parse the meta data
+  ContainerParser containerParser(containerSize);
-  tinyxml2::XMLDocument metaDataDoc;
-  const auto result = metaDataDoc.Parse(metaInfo);
-  free(metaInfo);
 
-  if (result != tinyxml2::XML_SUCCESS) {
+  if (!containerParser.setup()) {
-    Serial.printf("Could not parse META-INF/container.xml. Error: %d\n", result);
     return false;
   }
 
-  const auto container = metaDataDoc.FirstChildElement("container");
+  // Stream read (reusing your existing stream logic)
-  if (!container) {
+  if (!readItemContentsToStream(containerPath, containerParser, 512)) {
-    Serial.println("Could not find container element in META-INF/container.xml");
+    Serial.printf("[%lu] [EBP] Could not read META-INF/container.xml\n", millis());
+    containerParser.teardown();
     return false;
   }
 
-  const auto rootfiles = container->FirstChildElement("rootfiles");
+  // Extract the result
-  if (!rootfiles) {
+  if (containerParser.fullPath.empty()) {
-    Serial.println("Could not find rootfiles element in META-INF/container.xml");
+    Serial.printf("[%lu] [EBP] Could not find valid rootfile in container.xml\n", millis());
+    containerParser.teardown();
     return false;
   }
 
-  // find the root file that has the media-type="application/oebps-package+xml"
+  *contentOpfFile = std::move(containerParser.fullPath);
-  auto rootfile = rootfiles->FirstChildElement("rootfile");
-  while (rootfile) {
-    const char* mediaType = rootfile->Attribute("media-type");
-    if (mediaType && strcmp(mediaType, "application/oebps-package+xml") == 0) {
-      const char* full_path = rootfile->Attribute("full-path");
-      if (full_path) {
-        contentOpfFile = full_path;
-        return true;
-      }
-    }
-    rootfile = rootfile->NextSiblingElement("rootfile");
-  }
 
-  Serial.println("Could not get path to content.opf file");
+  containerParser.teardown();
-  return false;
-}
-
-bool Epub::parseContentOpf(ZipFile& zip, std::string& content_opf_file) {
-  // read in the content.opf file and parse it
-  auto contents = reinterpret_cast<char*>(zip.readFileToMemory(content_opf_file.c_str(), nullptr, true));
-
-  // parse the contents
-  tinyxml2::XMLDocument doc;
-  auto result = doc.Parse(contents);
-  free(contents);
-
-  if (result != tinyxml2::XML_SUCCESS) {
-    Serial.printf("Error parsing content.opf - %s\n", tinyxml2::XMLDocument::ErrorIDToName(result));
-    return false;
-  }
-
-  auto package = doc.FirstChildElement("package");
-  if (!package) package = doc.FirstChildElement("opf:package");
-
-  if (!package) {
-    Serial.println("Could not find package element in content.opf");
-    return false;
-  }
-
-  // get the metadata - title and cover image
-  auto metadata = package->FirstChildElement("metadata");
-  if (!metadata) metadata = package->FirstChildElement("opf:metadata");
-  if (!metadata) {
-    Serial.println("Missing metadata");
-    return false;
-  }
-
-  auto titleEl = metadata->FirstChildElement("dc:title");
-  if (!titleEl) {
-    Serial.println("Missing title");
-    return false;
-  }
-  this->title = titleEl->GetText();
-
-  auto cover = metadata->FirstChildElement("meta");
-  if (!cover) cover = metadata->FirstChildElement("opf:meta");
-  while (cover && cover->Attribute("name") && strcmp(cover->Attribute("name"), "cover") != 0) {
-    cover = cover->NextSiblingElement("meta");
-  }
-  if (!cover) {
-    Serial.println("Missing cover");
-  }
-  auto coverItem = cover ? cover->Attribute("content") : nullptr;
-
-  // read the manifest and spine
-  // the manifest gives us the names of the files
-  // the spine gives us the order of the files
-  // we can then read the files in the order they are in the spine
-  auto manifest = package->FirstChildElement("manifest");
-  if (!manifest) manifest = package->FirstChildElement("opf:manifest");
-  if (!manifest) {
-    Serial.println("Missing manifest");
-    return false;
-  }
-
-  // create a mapping from id to file name
-  auto item = manifest->FirstChildElement("item");
-  if (!item) item = manifest->FirstChildElement("opf:item");
-  std::map<std::string, std::string> items;
-
-  while (item) {
-    std::string itemId = item->Attribute("id");
-    std::string href = contentBasePath + item->Attribute("href");
-
-    // grab the cover image
-    if (coverItem && itemId == coverItem) {
-      coverImageItem = href;
-    }
-
-    // grab the ncx file
-    if (itemId == "ncx" || itemId == "ncxtoc") {
-      tocNcxItem = href;
-    }
-
-    items[itemId] = href;
-    auto nextItem = item->NextSiblingElement("item");
-    if (!nextItem) nextItem = item->NextSiblingElement("opf:item");
-    item = nextItem;
-  }
-
-  // find the spine
-  auto spineEl = package->FirstChildElement("spine");
-  if (!spineEl) spineEl = package->FirstChildElement("opf:spine");
-  if (!spineEl) {
-    Serial.println("Missing spine");
-    return false;
-  }
-
-  // read the spine
-  auto itemref = spineEl->FirstChildElement("itemref");
-  if (!itemref) itemref = spineEl->FirstChildElement("opf:itemref");
-  while (itemref) {
-    auto id = itemref->Attribute("idref");
-    if (items.find(id) != items.end()) {
-      spine.emplace_back(id, items[id]);
-    }
-    auto nextItemRef = itemref->NextSiblingElement("itemref");
-    if (!nextItemRef) nextItemRef = itemref->NextSiblingElement("opf:itemref");
-    itemref = nextItemRef;
-  }
   return true;
 }
 
-bool Epub::parseTocNcxFile(const ZipFile& zip) {
+bool Epub::parseContentOpf(const std::string& contentOpfFilePath) {
+  size_t contentOpfSize;
+  if (!getItemSize(contentOpfFilePath, &contentOpfSize)) {
+    Serial.printf("[%lu] [EBP] Could not get size of content.opf\n", millis());
+    return false;
+  }
+
+  ContentOpfParser opfParser(getBasePath(), contentOpfSize);
+
+  if (!opfParser.setup()) {
+    Serial.printf("[%lu] [EBP] Could not setup content.opf parser\n", millis());
+    return false;
+  }
+
+  if (!readItemContentsToStream(contentOpfFilePath, opfParser, 1024)) {
+    Serial.printf("[%lu] [EBP] Could not read content.opf\n", millis());
+    opfParser.teardown();
+    return false;
+  }
+
+  // Grab data from opfParser into epub
+  title = opfParser.title;
+
+  if (opfParser.items.count("ncx")) {
+    tocNcxItem = opfParser.items.at("ncx");
+  } else if (opfParser.items.count("ncxtoc")) {
+    tocNcxItem = opfParser.items.at("ncxtoc");
+  }
+
+  for (auto& spineRef : opfParser.spineRefs) {
+    if (opfParser.items.count(spineRef)) {
+      spine.emplace_back(spineRef, opfParser.items.at(spineRef));
+    }
+  }
+
+  Serial.printf("[%lu] [EBP] Successfully parsed content.opf\n", millis());
+
+  opfParser.teardown();
+  return true;
+}
+
+bool Epub::parseTocNcxFile() {
   // the ncx file should have been specified in the content.opf file
   if (tocNcxItem.empty()) {
-    Serial.println("No ncx file specified");
+    Serial.printf("[%lu] [EBP] No ncx file specified\n", millis());
     return false;
   }
 
-  const auto ncxData = reinterpret_cast<char*>(zip.readFileToMemory(tocNcxItem.c_str(), nullptr, true));
+  size_t tocSize;
-  if (!ncxData) {
+  if (!getItemSize(tocNcxItem, &tocSize)) {
-    Serial.printf("Could not find %s\n", tocNcxItem.c_str());
+    Serial.printf("[%lu] [EBP] Could not get size of toc ncx\n", millis());
     return false;
   }
 
-  // Parse the Toc contents
+  TocNcxParser ncxParser(contentBasePath, tocSize);
-  tinyxml2::XMLDocument doc;
-  const auto result = doc.Parse(ncxData);
-  free(ncxData);
 
-  if (result != tinyxml2::XML_SUCCESS) {
+  if (!ncxParser.setup()) {
-    Serial.printf("Error parsing toc %s\n", tinyxml2::XMLDocument::ErrorIDToName(result));
+    Serial.printf("[%lu] [EBP] Could not setup toc ncx parser\n", millis());
     return false;
   }
 
-  const auto ncx = doc.FirstChildElement("ncx");
+  if (!readItemContentsToStream(tocNcxItem, ncxParser, 1024)) {
-  if (!ncx) {
+    Serial.printf("[%lu] [EBP] Could not read toc ncx stream\n", millis());
-    Serial.println("Could not find first child ncx in toc");
+    ncxParser.teardown();
     return false;
   }
 
-  const auto navMap = ncx->FirstChildElement("navMap");
+  this->toc = std::move(ncxParser.toc);
-  if (!navMap) {
-    Serial.println("Could not find navMap child in ncx");
-    return false;
-  }
 
-  recursivelyParseNavMap(navMap->FirstChildElement("navPoint"));
+  Serial.printf("[%lu] [EBP] Parsed %d TOC items\n", millis(), this->toc.size());
+
+  ncxParser.teardown();
   return true;
 }
 
-void Epub::recursivelyParseNavMap(tinyxml2::XMLElement* element) {
-  // Fills toc map
-  while (element) {
-    std::string navTitle = element->FirstChildElement("navLabel")->FirstChildElement("text")->FirstChild()->Value();
-    const auto content = element->FirstChildElement("content");
-    std::string href = contentBasePath + content->Attribute("src");
-    // split the href on the # to get the href and the anchor
-    const size_t pos = href.find('#');
-    std::string anchor;
-
-    if (pos != std::string::npos) {
-      anchor = href.substr(pos + 1);
-      href = href.substr(0, pos);
-    }
-
-    toc.emplace_back(navTitle, href, anchor, 0);
-
-    tinyxml2::XMLElement* nestedNavPoint = element->FirstChildElement("navPoint");
-    if (nestedNavPoint) {
-      recursivelyParseNavMap(nestedNavPoint);
-    }
-    element = element->NextSiblingElement("navPoint");
-  }
-}
-
 // load in the meta data for the epub file
 bool Epub::load() {
+  Serial.printf("[%lu] [EBP] Loading ePub: %s\n", millis(), filepath.c_str());
   ZipFile zip("/sd" + filepath);
 
-  std::string contentOpfFile;
+  std::string contentOpfFilePath;
-  if (!findContentOpfFile(zip, contentOpfFile)) {
+  if (!findContentOpfFile(&contentOpfFilePath)) {
-    Serial.println("Could not open ePub");
+    Serial.printf("[%lu] [EBP] Could not find content.opf in zip\n", millis());
     return false;
   }
 
-  contentBasePath = contentOpfFile.substr(0, contentOpfFile.find_last_of('/') + 1);
+  Serial.printf("[%lu] [EBP] Found content.opf at: %s\n", millis(), contentOpfFilePath.c_str());
 
-  if (!parseContentOpf(zip, contentOpfFile)) {
+  contentBasePath = contentOpfFilePath.substr(0, contentOpfFilePath.find_last_of('/') + 1);
+
+  if (!parseContentOpf(contentOpfFilePath)) {
+    Serial.printf("[%lu] [EBP] Could not parse content.opf\n", millis());
     return false;
   }
 
-  if (!parseTocNcxFile(zip)) {
+  if (!parseTocNcxFile()) {
+    Serial.printf("[%lu] [EBP] Could not parse toc\n", millis());
     return false;
   }
 
+  Serial.printf("[%lu] [EBP] Loaded ePub: %s\n", millis(), filepath.c_str());
+
   return true;
 }
 
-void Epub::clearCache() const { SD.rmdir(cachePath.c_str()); }
+bool Epub::clearCache() const {
+  if (!SD.exists(cachePath.c_str())) {
+    Serial.printf("[%lu] [EPB] Cache does not exist, no action needed\n", millis());
+    return true;
+  }
+
+  if (!FsHelpers::removeDir(cachePath.c_str())) {
+    Serial.printf("[%lu] [EPB] Failed to clear cache\n", millis());
+    return false;
+  }
+
+  Serial.printf("[%lu] [EPB] Cache cleared successfully\n", millis());
+  return true;
+}
 
 void Epub::setupCacheDir() const {
   if (SD.exists(cachePath.c_str())) {
@@ -314,7 +231,7 @@ uint8_t* Epub::readItemContentsToBytes(const std::string& itemHref, size_t* size
 
   const auto content = zip.readFileToMemory(path.c_str(), size, trailingNullByte);
   if (!content) {
-    Serial.printf("Failed to read item %s\n", path.c_str());
+    Serial.printf("[%lu] [EBP] Failed to read item %s\n", millis(), path.c_str());
     return nullptr;
   }
 
@@ -328,11 +245,18 @@ bool Epub::readItemContentsToStream(const std::string& itemHref, Print& out, con
   return zip.readFileToStream(path.c_str(), out, chunkSize);
 }
 
+bool Epub::getItemSize(const std::string& itemHref, size_t* size) const {
+  const ZipFile zip("/sd" + filepath);
+  const std::string path = normalisePath(itemHref);
+
+  return zip.getInflatedFileSize(path.c_str(), size);
+}
+
 int Epub::getSpineItemsCount() const { return spine.size(); }
 
 std::string& Epub::getSpineItem(const int spineIndex) {
   if (spineIndex < 0 || spineIndex >= spine.size()) {
-    Serial.printf("getSpineItem index:%d is out of range\n", spineIndex);
+    Serial.printf("[%lu] [EBP] getSpineItem index:%d is out of range\n", millis(), spineIndex);
     return spine.at(0).second;
   }
 
@@ -341,7 +265,7 @@ std::string& Epub::getSpineItem(const int spineIndex) {
 
 EpubTocEntry& Epub::getTocItem(const int tocTndex) {
   if (tocTndex < 0 || tocTndex >= toc.size()) {
-    Serial.printf("getTocItem index:%d is out of range\n", tocTndex);
+    Serial.printf("[%lu] [EBP] getTocItem index:%d is out of range\n", millis(), tocTndex);
     return toc.at(0);
   }
 
@@ -360,7 +284,7 @@ int Epub::getSpineIndexForTocIndex(const int tocIndex) const {
     }
   }
 
-  Serial.println("Section not found");
+  Serial.printf("[%lu] [EBP] Section not found\n", millis());
   // not found - default to the start of the book
   return 0;
 }
@@ -374,7 +298,6 @@ int Epub::getTocIndexForSpineIndex(const int spineIndex) const {
     }
   }
 
-  Serial.println("TOC item not found");
+  Serial.printf("[%lu] [EBP] TOC item not found\n", millis());
-  // not found - default to first item
+  return -1;
-  return 0;
 }

lib/Epub/Epub.h

@@ -1,22 +1,13 @@
 #pragma once
-#include <HardwareSerial.h>
+#include <Print.h>
-#include <tinyxml2.h>
 
 #include <string>
 #include <unordered_map>
 #include <vector>
 
-class ZipFile;
+#include "Epub/EpubTocEntry.h"
 
-class EpubTocEntry {
+class ZipFile;
- public:
-  std::string title;
-  std::string href;
-  std::string anchor;
-  int level;
-  EpubTocEntry(std::string title, std::string href, std::string anchor, const int level)
-      : title(std::move(title)), href(std::move(href)), anchor(std::move(anchor)), level(level) {}
-};
 
 class Epub {
   // the title read from the EPUB meta data
@@ -36,11 +27,9 @@ class Epub {
   // Uniq cache key based on filepath
   std::string cachePath;
 
-  // find the path for the content.opf file
+  bool findContentOpfFile(std::string* contentOpfFile) const;
-  static bool findContentOpfFile(const ZipFile& zip, std::string& contentOpfFile);
+  bool parseContentOpf(const std::string& contentOpfFilePath);
-  bool parseContentOpf(ZipFile& zip, std::string& content_opf_file);
+  bool parseTocNcxFile();
-  bool parseTocNcxFile(const ZipFile& zip);
-  void recursivelyParseNavMap(tinyxml2::XMLElement* element);
 
  public:
   explicit Epub(std::string filepath, const std::string& cacheDir) : filepath(std::move(filepath)) {
@@ -50,7 +39,7 @@ class Epub {
   ~Epub() = default;
   std::string& getBasePath() { return contentBasePath; }
   bool load();
-  void clearCache() const;
+  bool clearCache() const;
   void setupCacheDir() const;
   const std::string& getCachePath() const;
   const std::string& getPath() const;
@@ -59,6 +48,7 @@ class Epub {
   uint8_t* readItemContentsToBytes(const std::string& itemHref, size_t* size = nullptr,
                                    bool trailingNullByte = false) const;
   bool readItemContentsToStream(const std::string& itemHref, Print& out, size_t chunkSize) const;
+  bool getItemSize(const std::string& itemHref, size_t* size) const;
   std::string& getSpineItem(int spineIndex);
   int getSpineItemsCount() const;
   EpubTocEntry& getTocItem(int tocTndex);

lib/Epub/Epub/EpubHtmlParserSlim.h

@@ -1,42 +0,0 @@
-#pragma once
-
-#include <expat.h>
-#include <limits.h>
-
-#include <functional>
-
-#include "blocks/TextBlock.h"
-
-class Page;
-class EpdRenderer;
-
-#define PART_WORD_BUFFER_SIZE 200
-
-class EpubHtmlParserSlim {
-  const char* filepath;
-  EpdRenderer& renderer;
-  std::function<void(Page*)> completePageFn;
-  int depth = 0;
-  int skipUntilDepth = INT_MAX;
-  int boldUntilDepth = INT_MAX;
-  int italicUntilDepth = INT_MAX;
-  // If we encounter words longer than this, but this is pretty large
-  char partWordBuffer[PART_WORD_BUFFER_SIZE] = {};
-  int partWordBufferIndex = 0;
-  TextBlock* currentTextBlock = nullptr;
-  Page* currentPage = nullptr;
-
-  void startNewTextBlock(BLOCK_STYLE style);
-  void makePages();
-  // XML callbacks
-  static void XMLCALL startElement(void* userData, const XML_Char* name, const XML_Char** atts);
-  static void XMLCALL characterData(void* userData, const XML_Char* s, int len);
-  static void XMLCALL endElement(void* userData, const XML_Char* name);
-
- public:
-  explicit EpubHtmlParserSlim(const char* filepath, EpdRenderer& renderer,
-                              const std::function<void(Page*)>& completePageFn)
-      : filepath(filepath), renderer(renderer), completePageFn(completePageFn) {}
-  ~EpubHtmlParserSlim() = default;
-  bool parseAndBuildPages();
-};

lib/Epub/Epub/EpubTocEntry.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <string>
+
+class EpubTocEntry {
+ public:
+  std::string title;
+  std::string href;
+  std::string anchor;
+  int level;
+  EpubTocEntry(std::string title, std::string href, std::string anchor, const int level)
+      : title(std::move(title)), href(std::move(href)), anchor(std::move(anchor)), level(level) {}
+};

lib/Epub/Epub/FsHelpers.cpp

@@ -0,0 +1,36 @@
+#include "FsHelpers.h"
+
+#include <SD.h>
+
+bool FsHelpers::removeDir(const char* path) {
+  // 1. Open the directory
+  File dir = SD.open(path);
+  if (!dir) {
+    return false;
+  }
+  if (!dir.isDirectory()) {
+    return false;
+  }
+
+  File file = dir.openNextFile();
+  while (file) {
+    String filePath = path;
+    if (!filePath.endsWith("/")) {
+      filePath += "/";
+    }
+    filePath += file.name();
+
+    if (file.isDirectory()) {
+      if (!removeDir(filePath.c_str())) {
+        return false;
+      }
+    } else {
+      if (!SD.remove(filePath.c_str())) {
+        return false;
+      }
+    }
+    file = dir.openNextFile();
+  }
+
+  return SD.rmdir(path);
+}

lib/Epub/Epub/FsHelpers.h

@@ -0,0 +1,6 @@
+#pragma once
+
+class FsHelpers {
+ public:
+  static bool removeDir(const char* path);
+};

lib/Epub/Epub/Page.cpp

@@ -3,48 +3,56 @@
 #include <HardwareSerial.h>
 #include <Serialization.h>
 
-void PageLine::render(EpdRenderer& renderer) { block->render(renderer, 0, yPos); }
+constexpr uint8_t PAGE_FILE_VERSION = 3;
+
+void PageLine::render(GfxRenderer& renderer, const int fontId) { block->render(renderer, fontId, xPos, yPos); }
 
 void PageLine::serialize(std::ostream& os) {
+  serialization::writePod(os, xPos);
   serialization::writePod(os, yPos);
 
   // serialize TextBlock pointed to by PageLine
   block->serialize(os);
 }
 
-PageLine* PageLine::deserialize(std::istream& is) {
+std::unique_ptr<PageLine> PageLine::deserialize(std::istream& is) {
-  int32_t yPos;
+  int16_t xPos;
+  int16_t yPos;
+  serialization::readPod(is, xPos);
   serialization::readPod(is, yPos);
 
-  const auto tb = TextBlock::deserialize(is);
+  auto tb = TextBlock::deserialize(is);
-  return new PageLine(tb, yPos);
+  return std::unique_ptr<PageLine>(new PageLine(std::move(tb), xPos, yPos));
 }
 
-void Page::render(EpdRenderer& renderer) const {
+void Page::render(GfxRenderer& renderer, const int fontId) const {
-  const auto start = millis();
+  for (auto& element : elements) {
-  for (const auto element : elements) {
+    element->render(renderer, fontId);
-    element->render(renderer);
   }
-  Serial.printf("Rendered page elements (%u) in %dms\n", elements.size(), millis() - start);
 }
 
 void Page::serialize(std::ostream& os) const {
-  serialization::writePod(os, nextY);
+  serialization::writePod(os, PAGE_FILE_VERSION);
 
   const uint32_t count = elements.size();
   serialization::writePod(os, count);
 
-  for (auto* el : elements) {
+  for (const auto& el : elements) {
     // Only PageLine exists currently
     serialization::writePod(os, static_cast<uint8_t>(TAG_PageLine));
-    static_cast<PageLine*>(el)->serialize(os);
+    el->serialize(os);
   }
 }
 
-Page* Page::deserialize(std::istream& is) {
+std::unique_ptr<Page> Page::deserialize(std::istream& is) {
-  auto* page = new Page();
+  uint8_t version;
+  serialization::readPod(is, version);
+  if (version != PAGE_FILE_VERSION) {
+    Serial.printf("[%lu] [PGE] Deserialization failed: Unknown version %u\n", millis(), version);
+    return nullptr;
+  }
 
-  serialization::readPod(is, page->nextY);
+  auto page = std::unique_ptr<Page>(new Page());
 
   uint32_t count;
   serialization::readPod(is, count);
@@ -54,10 +62,11 @@ Page* Page::deserialize(std::istream& is) {
     serialization::readPod(is, tag);
 
     if (tag == TAG_PageLine) {
-      auto* pl = PageLine::deserialize(is);
+      auto pl = PageLine::deserialize(is);
-      page->elements.push_back(pl);
+      page->elements.push_back(std::move(pl));
     } else {
-      throw std::runtime_error("Unknown PageElement tag");
+      Serial.printf("[%lu] [PGE] Deserialization failed: Unknown tag %u\n", millis(), tag);
+      return nullptr;
     }
   }
 

lib/Epub/Epub/Page.h

@@ -1,4 +1,7 @@
 #pragma once
+#include <utility>
+#include <vector>
+
 #include "blocks/TextBlock.h"
 
 enum PageElementTag : uint8_t {
@@ -8,36 +11,31 @@ enum PageElementTag : uint8_t {
 // represents something that has been added to a page
 class PageElement {
  public:
-  int yPos;
+  int16_t xPos;
-  explicit PageElement(const int yPos) : yPos(yPos) {}
+  int16_t yPos;
+  explicit PageElement(const int16_t xPos, const int16_t yPos) : xPos(xPos), yPos(yPos) {}
   virtual ~PageElement() = default;
-  virtual void render(EpdRenderer& renderer) = 0;
+  virtual void render(GfxRenderer& renderer, int fontId) = 0;
   virtual void serialize(std::ostream& os) = 0;
 };
 
 // a line from a block element
 class PageLine final : public PageElement {
-  const TextBlock* block;
+  std::shared_ptr<TextBlock> block;
 
  public:
-  PageLine(const TextBlock* block, const int yPos) : PageElement(yPos), block(block) {}
+  PageLine(std::shared_ptr<TextBlock> block, const int16_t xPos, const int16_t yPos)
-  ~PageLine() override { delete block; }
+      : PageElement(xPos, yPos), block(std::move(block)) {}
-  void render(EpdRenderer& renderer) override;
+  void render(GfxRenderer& renderer, int fontId) override;
   void serialize(std::ostream& os) override;
-  static PageLine* deserialize(std::istream& is);
+  static std::unique_ptr<PageLine> deserialize(std::istream& is);
 };
 
 class Page {
  public:
-  int nextY = 0;
   // the list of block index and line numbers on this page
-  std::vector<PageElement*> elements;
+  std::vector<std::shared_ptr<PageElement>> elements;
-  void render(EpdRenderer& renderer) const;
+  void render(GfxRenderer& renderer, int fontId) const;
-  ~Page() {
-    for (const auto element : elements) {
-      delete element;
-    }
-  }
   void serialize(std::ostream& os) const;
-  static Page* deserialize(std::istream& is);
+  static std::unique_ptr<Page> deserialize(std::istream& is);
 };

lib/Epub/Epub/ParsedText.cpp

@@ -0,0 +1,164 @@
+#include "ParsedText.h"
+
+#include <GfxRenderer.h>
+
+#include <algorithm>
+#include <cmath>
+#include <functional>
+#include <limits>
+#include <vector>
+
+constexpr int MAX_COST = std::numeric_limits<int>::max();
+
+void ParsedText::addWord(std::string word, const EpdFontStyle fontStyle) {
+  if (word.empty()) return;
+
+  words.push_back(std::move(word));
+  wordStyles.push_back(fontStyle);
+}
+
+// Consumes data to minimize memory usage
+void ParsedText::layoutAndExtractLines(const GfxRenderer& renderer, const int fontId, const int horizontalMargin,
+                                       const std::function<void(std::shared_ptr<TextBlock>)>& processLine) {
+  if (words.empty()) {
+    return;
+  }
+
+  const size_t totalWordCount = words.size();
+  const int pageWidth = renderer.getScreenWidth() - horizontalMargin;
+  const int spaceWidth = renderer.getSpaceWidth(fontId);
+
+  std::vector<uint16_t> wordWidths;
+  wordWidths.reserve(totalWordCount);
+
+  auto wordsIt = words.begin();
+  auto wordStylesIt = wordStyles.begin();
+
+  while (wordsIt != words.end()) {
+    wordWidths.push_back(renderer.getTextWidth(fontId, wordsIt->c_str(), *wordStylesIt));
+
+    std::advance(wordsIt, 1);
+    std::advance(wordStylesIt, 1);
+  }
+
+  // DP table to store the minimum badness (cost) of lines starting at index i
+  std::vector<int> dp(totalWordCount);
+  // 'ans[i]' stores the index 'j' of the *last word* in the optimal line starting at 'i'
+  std::vector<size_t> ans(totalWordCount);
+
+  // Base Case
+  dp[totalWordCount - 1] = 0;
+  ans[totalWordCount - 1] = totalWordCount - 1;
+
+  for (int i = totalWordCount - 2; i >= 0; --i) {
+    int currlen = -spaceWidth;
+    dp[i] = MAX_COST;
+
+    for (size_t j = i; j < totalWordCount; ++j) {
+      // Current line length: previous width + space + current word width
+      currlen += wordWidths[j] + spaceWidth;
+
+      if (currlen > pageWidth) {
+        break;
+      }
+
+      int cost;
+      if (j == totalWordCount - 1) {
+        cost = 0;  // Last line
+      } else {
+        const int remainingSpace = pageWidth - currlen;
+        // Use long long for the square to prevent overflow
+        const long long cost_ll = static_cast<long long>(remainingSpace) * remainingSpace + dp[j + 1];
+
+        if (cost_ll > MAX_COST) {
+          cost = MAX_COST;
+        } else {
+          cost = static_cast<int>(cost_ll);
+        }
+      }
+
+      if (cost < dp[i]) {
+        dp[i] = cost;
+        ans[i] = j;  // j is the index of the last word in this optimal line
+      }
+    }
+  }
+
+  // Stores the index of the word that starts the next line (last_word_index + 1)
+  std::vector<size_t> lineBreakIndices;
+  size_t currentWordIndex = 0;
+  constexpr size_t MAX_LINES = 1000;
+
+  while (currentWordIndex < totalWordCount) {
+    if (lineBreakIndices.size() >= MAX_LINES) {
+      break;
+    }
+
+    size_t nextBreakIndex = ans[currentWordIndex] + 1;
+    lineBreakIndices.push_back(nextBreakIndex);
+
+    currentWordIndex = nextBreakIndex;
+  }
+
+  // Initialize iterators for consumption
+  auto wordStartIt = words.begin();
+  auto wordStyleStartIt = wordStyles.begin();
+  size_t wordWidthIndex = 0;
+
+  size_t lastBreakAt = 0;
+  for (const size_t lineBreak : lineBreakIndices) {
+    const size_t lineWordCount = lineBreak - lastBreakAt;
+
+    // Calculate end iterators for the range to splice
+    auto wordEndIt = wordStartIt;
+    auto wordStyleEndIt = wordStyleStartIt;
+    std::advance(wordEndIt, lineWordCount);
+    std::advance(wordStyleEndIt, lineWordCount);
+
+    // Calculate total word width for this line
+    int lineWordWidthSum = 0;
+    for (size_t i = 0; i < lineWordCount; ++i) {
+      lineWordWidthSum += wordWidths[wordWidthIndex + i];
+    }
+
+    // Calculate spacing
+    const int spareSpace = pageWidth - lineWordWidthSum;
+    int spacing = spaceWidth;
+    const bool isLastLine = lineBreak == totalWordCount;
+
+    if (style == TextBlock::JUSTIFIED && !isLastLine && lineWordCount >= 2) {
+      spacing = spareSpace / (lineWordCount - 1);
+    }
+
+    // Calculate initial x position
+    uint16_t xpos = 0;
+    if (style == TextBlock::RIGHT_ALIGN) {
+      xpos = spareSpace - (lineWordCount - 1) * spaceWidth;
+    } else if (style == TextBlock::CENTER_ALIGN) {
+      xpos = (spareSpace - (lineWordCount - 1) * spaceWidth) / 2;
+    }
+
+    // Pre-calculate X positions for words
+    std::list<uint16_t> lineXPos;
+    for (size_t i = 0; i < lineWordCount; ++i) {
+      const uint16_t currentWordWidth = wordWidths[wordWidthIndex + i];
+      lineXPos.push_back(xpos);
+      xpos += currentWordWidth + spacing;
+    }
+
+    // *** CRITICAL STEP: CONSUME DATA USING SPLICE ***
+    std::list<std::string> lineWords;
+    lineWords.splice(lineWords.begin(), words, wordStartIt, wordEndIt);
+    std::list<EpdFontStyle> lineWordStyles;
+    lineWordStyles.splice(lineWordStyles.begin(), wordStyles, wordStyleStartIt, wordStyleEndIt);
+
+    processLine(
+        std::make_shared<TextBlock>(std::move(lineWords), std::move(lineXPos), std::move(lineWordStyles), style));
+
+    // Update pointers/indices for the next line
+    wordStartIt = wordEndIt;
+    wordStyleStartIt = wordStyleEndIt;
+    wordWidthIndex += lineWordCount;
+    lastBreakAt = lineBreak;
+  }
+}

lib/Epub/Epub/ParsedText.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <EpdFontFamily.h>
+
+#include <cstdint>
+#include <functional>
+#include <list>
+#include <memory>
+#include <string>
+
+#include "blocks/TextBlock.h"
+
+class GfxRenderer;
+
+class ParsedText {
+  std::list<std::string> words;
+  std::list<EpdFontStyle> wordStyles;
+  TextBlock::BLOCK_STYLE style;
+
+ public:
+  explicit ParsedText(const TextBlock::BLOCK_STYLE style) : style(style) {}
+  ~ParsedText() = default;
+
+  void addWord(std::string word, EpdFontStyle fontStyle);
+  void setStyle(const TextBlock::BLOCK_STYLE style) { this->style = style; }
+  TextBlock::BLOCK_STYLE getStyle() const { return style; }
+  bool isEmpty() const { return words.empty(); }
+  void layoutAndExtractLines(const GfxRenderer& renderer, int fontId, int horizontalMargin,
+                             const std::function<void(std::shared_ptr<TextBlock>)>& processLine);
+};

lib/Epub/Epub/Section.cpp

@@ -1,37 +1,44 @@
 #include "Section.h"
 
-#include <EpdRenderer.h>
 #include <SD.h>
+#include <Serialization.h>
 
 #include <fstream>
 
-#include "EpubHtmlParserSlim.h"
+#include "FsHelpers.h"
 #include "Page.h"
-#include "Serialization.h"
+#include "parsers/ChapterHtmlSlimParser.h"
 
-constexpr uint8_t SECTION_FILE_VERSION = 2;
+constexpr uint8_t SECTION_FILE_VERSION = 4;
-
-void Section::onPageComplete(const Page* page) {
-  Serial.printf("Page %d complete - free mem: %lu\n", pageCount, ESP.getFreeHeap());
 
+void Section::onPageComplete(std::unique_ptr<Page> page) {
   const auto filePath = cachePath + "/page_" + std::to_string(pageCount) + ".bin";
 
   std::ofstream outputFile("/sd" + filePath);
   page->serialize(outputFile);
   outputFile.close();
 
+  Serial.printf("[%lu] [SCT] Page %d processed\n", millis(), pageCount);
+
   pageCount++;
-  delete page;
 }
 
-void Section::writeCacheMetadata() const {
+void Section::writeCacheMetadata(const int fontId, const float lineCompression, const int marginTop,
+                                 const int marginRight, const int marginBottom, const int marginLeft) const {
   std::ofstream outputFile(("/sd" + cachePath + "/section.bin").c_str());
   serialization::writePod(outputFile, SECTION_FILE_VERSION);
+  serialization::writePod(outputFile, fontId);
+  serialization::writePod(outputFile, lineCompression);
+  serialization::writePod(outputFile, marginTop);
+  serialization::writePod(outputFile, marginRight);
+  serialization::writePod(outputFile, marginBottom);
+  serialization::writePod(outputFile, marginLeft);
   serialization::writePod(outputFile, pageCount);
   outputFile.close();
 }
 
-bool Section::loadCacheMetadata() {
+bool Section::loadCacheMetadata(const int fontId, const float lineCompression, const int marginTop,
+                                const int marginRight, const int marginBottom, const int marginLeft) {
   if (!SD.exists(cachePath.c_str())) {
     return false;
   }
@@ -42,17 +49,39 @@ bool Section::loadCacheMetadata() {
   }
 
   std::ifstream inputFile(("/sd" + sectionFilePath).c_str());
-  uint8_t version;
+
-  serialization::readPod(inputFile, version);
+  // Match parameters
-  if (version != SECTION_FILE_VERSION) {
+  {
-    inputFile.close();
+    uint8_t version;
-    SD.remove(sectionFilePath.c_str());
+    serialization::readPod(inputFile, version);
-    Serial.printf("Section state file: Unknown version %u\n", version);
+    if (version != SECTION_FILE_VERSION) {
-    return false;
+      inputFile.close();
+      Serial.printf("[%lu] [SCT] Deserialization failed: Unknown version %u\n", millis(), version);
+      clearCache();
+      return false;
+    }
+
+    int fileFontId, fileMarginTop, fileMarginRight, fileMarginBottom, fileMarginLeft;
+    float fileLineCompression;
+    serialization::readPod(inputFile, fileFontId);
+    serialization::readPod(inputFile, fileLineCompression);
+    serialization::readPod(inputFile, fileMarginTop);
+    serialization::readPod(inputFile, fileMarginRight);
+    serialization::readPod(inputFile, fileMarginBottom);
+    serialization::readPod(inputFile, fileMarginLeft);
+
+    if (fontId != fileFontId || lineCompression != fileLineCompression || marginTop != fileMarginTop ||
+        marginRight != fileMarginRight || marginBottom != fileMarginBottom || marginLeft != fileMarginLeft) {
+      inputFile.close();
+      Serial.printf("[%lu] [SCT] Deserialization failed: Parameters do not match\n", millis());
+      clearCache();
+      return false;
+    }
   }
+
   serialization::readPod(inputFile, pageCount);
   inputFile.close();
-  Serial.printf("Loaded cache: %d pages\n", pageCount);
+  Serial.printf("[%lu] [SCT] Deserialization succeeded: %d pages\n", millis(), pageCount);
   return true;
 }
 
@@ -61,9 +90,24 @@ void Section::setupCacheDir() const {
   SD.mkdir(cachePath.c_str());
 }
 
-void Section::clearCache() const { SD.rmdir(cachePath.c_str()); }
+// Your updated class method (assuming you are using the 'SD' object, which is a wrapper for a specific filesystem)
+bool Section::clearCache() const {
+  if (!SD.exists(cachePath.c_str())) {
+    Serial.printf("[%lu] [SCT] Cache does not exist, no action needed\n", millis());
+    return true;
+  }
 
-bool Section::persistPageDataToSD() {
+  if (!FsHelpers::removeDir(cachePath.c_str())) {
+    Serial.printf("[%lu] [SCT] Failed to clear cache\n", millis());
+    return false;
+  }
+
+  Serial.printf("[%lu] [SCT] Cache cleared successfully\n", millis());
+  return true;
+}
+
+bool Section::persistPageDataToSD(const int fontId, const float lineCompression, const int marginTop,
+                                  const int marginRight, const int marginBottom, const int marginLeft) {
   const auto localPath = epub->getSpineItem(spineIndex);
 
   // TODO: Should we get rid of this file all together?
@@ -75,44 +119,39 @@ bool Section::persistPageDataToSD() {
   f.close();
 
   if (!success) {
-    Serial.println("Failed to stream item contents");
+    Serial.printf("[%lu] [SCT] Failed to stream item contents to temp file\n", millis());
     return false;
   }
 
-  Serial.printf("Streamed HTML to %s\n", tmpHtmlPath.c_str());
+  Serial.printf("[%lu] [SCT] Streamed temp HTML to %s\n", millis(), tmpHtmlPath.c_str());
 
   const auto sdTmpHtmlPath = "/sd" + tmpHtmlPath;
 
-  auto visitor =
+  ChapterHtmlSlimParser visitor(sdTmpHtmlPath.c_str(), renderer, fontId, lineCompression, marginTop, marginRight,
-      EpubHtmlParserSlim(sdTmpHtmlPath.c_str(), renderer, [this](const Page* page) { this->onPageComplete(page); });
+                                marginBottom, marginLeft,
+                                [this](std::unique_ptr<Page> page) { this->onPageComplete(std::move(page)); });
   success = visitor.parseAndBuildPages();
 
   SD.remove(tmpHtmlPath.c_str());
   if (!success) {
-    Serial.println("Failed to parse and build pages");
+    Serial.printf("[%lu] [SCT] Failed to parse XML and build pages\n", millis());
     return false;
   }
 
-  writeCacheMetadata();
+  writeCacheMetadata(fontId, lineCompression, marginTop, marginRight, marginBottom, marginLeft);
 
   return true;
 }
 
-void Section::renderPage() const {
+std::unique_ptr<Page> Section::loadPageFromSD() const {
-  if (0 <= currentPage && currentPage < pageCount) {
+  const auto filePath = "/sd" + cachePath + "/page_" + std::to_string(currentPage) + ".bin";
-    const auto filePath = "/sd" + cachePath + "/page_" + std::to_string(currentPage) + ".bin";
+  if (!SD.exists(filePath.c_str() + 3)) {
-    std::ifstream inputFile(filePath);
+    Serial.printf("[%lu] [SCT] Page file does not exist: %s\n", millis(), filePath.c_str());
-    const Page* p = Page::deserialize(inputFile);
+    return nullptr;
-    inputFile.close();
-    p->render(renderer);
-    delete p;
-  } else if (pageCount == 0) {
-    Serial.println("No pages to render");
-    const int width = renderer.getTextWidth("Empty chapter", BOLD);
-    renderer.drawText((renderer.getPageWidth() - width) / 2, 300, "Empty chapter", 1, BOLD);
-  } else {
-    Serial.printf("Page out of bounds: %d (max %d)\n", currentPage, pageCount);
-    const int width = renderer.getTextWidth("Out of bounds", BOLD);
-    renderer.drawText((renderer.getPageWidth() - width) / 2, 300, "Out of bounds", 1, BOLD);
   }
+
+  std::ifstream inputFile(filePath);
+  auto page = Page::deserialize(inputFile);
+  inputFile.close();
+  return page;
 }

lib/Epub/Epub/Section.h

@@ -1,30 +1,35 @@
 #pragma once
+#include <memory>
+
 #include "Epub.h"
 
 class Page;
-class EpdRenderer;
+class GfxRenderer;
 
 class Section {
-  Epub* epub;
+  std::shared_ptr<Epub> epub;
   const int spineIndex;
-  EpdRenderer& renderer;
+  GfxRenderer& renderer;
   std::string cachePath;
 
-  void onPageComplete(const Page* page);
+  void writeCacheMetadata(int fontId, float lineCompression, int marginTop, int marginRight, int marginBottom,
+                          int marginLeft) const;
+  void onPageComplete(std::unique_ptr<Page> page);
 
  public:
   int pageCount = 0;
   int currentPage = 0;
 
-  explicit Section(Epub* epub, const int spineIndex, EpdRenderer& renderer)
+  explicit Section(const std::shared_ptr<Epub>& epub, const int spineIndex, GfxRenderer& renderer)
       : epub(epub), spineIndex(spineIndex), renderer(renderer) {
     cachePath = epub->getCachePath() + "/" + std::to_string(spineIndex);
   }
   ~Section() = default;
-  void writeCacheMetadata() const;
+  bool loadCacheMetadata(int fontId, float lineCompression, int marginTop, int marginRight, int marginBottom,
-  bool loadCacheMetadata();
+                         int marginLeft);
   void setupCacheDir() const;
-  void clearCache() const;
+  bool clearCache() const;
-  bool persistPageDataToSD();
+  bool persistPageDataToSD(int fontId, float lineCompression, int marginTop, int marginRight, int marginBottom,
-  void renderPage() const;
+                           int marginLeft);
+  std::unique_ptr<Page> loadPageFromSD() const;
 };

lib/Epub/Epub/blocks/Block.h

@@ -1,6 +1,6 @@
 #pragma once
 
-class EpdRenderer;
+class GfxRenderer;
 
 typedef enum { TEXT_BLOCK, IMAGE_BLOCK } BlockType;
 
@@ -8,7 +8,7 @@ typedef enum { TEXT_BLOCK, IMAGE_BLOCK } BlockType;
 class Block {
  public:
   virtual ~Block() = default;
-  virtual void layout(EpdRenderer& renderer) = 0;
+  virtual void layout(GfxRenderer& renderer) = 0;
   virtual BlockType getType() = 0;
   virtual bool isEmpty() = 0;
   virtual void finish() {}

lib/Epub/Epub/blocks/TextBlock.cpp

@@ -1,171 +1,19 @@
 #include "TextBlock.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
 #include <Serialization.h>
 
-void TextBlock::addWord(const std::string& word, const bool is_bold, const bool is_italic) {
+void TextBlock::render(const GfxRenderer& renderer, const int fontId, const int x, const int y) const {
-  if (word.length() == 0) return;
+  auto wordIt = words.begin();
+  auto wordStylesIt = wordStyles.begin();
+  auto wordXposIt = wordXpos.begin();
 
-  words.push_back(word);
-  wordStyles.push_back((is_bold ? BOLD_SPAN : 0) | (is_italic ? ITALIC_SPAN : 0));
-}
-
-std::list<TextBlock*> TextBlock::splitIntoLines(const EpdRenderer& renderer) {
-  const int totalWordCount = words.size();
-  const int pageWidth = renderer.getPageWidth();
-  const int spaceWidth = renderer.getSpaceWidth();
-
-  words.shrink_to_fit();
-  wordStyles.shrink_to_fit();
-  wordXpos.reserve(totalWordCount);
-
-  // measure each word
-  uint16_t wordWidths[totalWordCount];
   for (int i = 0; i < words.size(); i++) {
-    // measure the word
+    renderer.drawText(fontId, *wordXposIt + x, y, wordIt->c_str(), true, *wordStylesIt);
-    EpdFontStyle fontStyle = REGULAR;
-    if (wordStyles[i] & BOLD_SPAN) {
-      if (wordStyles[i] & ITALIC_SPAN) {
-        fontStyle = BOLD_ITALIC;
-      } else {
-        fontStyle = BOLD;
-      }
-    } else if (wordStyles[i] & ITALIC_SPAN) {
-      fontStyle = ITALIC;
-    }
-    const int width = renderer.getTextWidth(words[i].c_str(), fontStyle);
-    wordWidths[i] = width;
-  }
 
-  // now apply the dynamic programming algorithm to find the best line breaks
+    std::advance(wordIt, 1);
-  // DP table in which dp[i] represents cost of line starting with word words[i]
+    std::advance(wordStylesIt, 1);
-  int dp[totalWordCount];
+    std::advance(wordXposIt, 1);
-
-  // Array in which ans[i] store index of last word in line starting with word
-  // word[i]
-  size_t ans[totalWordCount];
-
-  // If only one word is present then only one line is required. Cost of last
-  // line is zero. Hence cost of this line is zero. Ending point is also n-1 as
-  // single word is present
-  dp[totalWordCount - 1] = 0;
-  ans[totalWordCount - 1] = totalWordCount - 1;
-
-  // Make each word first word of line by iterating over each index in arr.
-  for (int i = totalWordCount - 2; i >= 0; i--) {
-    int currlen = -1;
-    dp[i] = INT_MAX;
-
-    // Variable to store possible minimum cost of line.
-    int cost;
-
-    // Keep on adding words in current line by iterating from starting word upto
-    // last word in arr.
-    for (int j = i; j < totalWordCount; j++) {
-      // Update the width of the words in current line + the space between two
-      // words.
-      currlen += wordWidths[j] + spaceWidth;
-
-      // If we're bigger than the current pagewidth then we can't add more words
-      if (currlen > pageWidth) break;
-
-      // if we've run out of words then this is last line and the cost should be
-      // 0 Otherwise the cost is the sqaure of the left over space + the costs
-      // of all the previous lines
-      if (j == totalWordCount - 1)
-        cost = 0;
-      else
-        cost = (pageWidth - currlen) * (pageWidth - currlen) + dp[j + 1];
-
-      // Check if this arrangement gives minimum cost for line starting with
-      // word words[i].
-      if (cost < dp[i]) {
-        dp[i] = cost;
-        ans[i] = j;
-      }
-    }
-  }
-
-  // We can now iterate through the answer to find the line break positions
-  std::list<uint16_t> lineBreaks;
-  for (size_t i = 0; i < totalWordCount;) {
-    i = ans[i] + 1;
-    if (i > totalWordCount) {
-      break;
-    }
-    lineBreaks.push_back(i);
-    // Text too big, just exit
-    if (lineBreaks.size() > 1000) {
-      break;
-    }
-  }
-
-  std::list<TextBlock*> lines;
-
-  // With the line breaks calculated we can now position the words along the
-  // line
-  int startWord = 0;
-  for (const auto lineBreak : lineBreaks) {
-    const int lineWordCount = lineBreak - startWord;
-
-    int lineWordWidthSum = 0;
-    for (int i = startWord; i < lineBreak; i++) {
-      lineWordWidthSum += wordWidths[i];
-    }
-
-    // Calculate spacing between words
-    const uint16_t spareSpace = pageWidth - lineWordWidthSum;
-    uint16_t spacing = spaceWidth;
-    // evenly space words if using justified style, not the last line, and at
-    // least 2 words
-    if (style == JUSTIFIED && lineBreak != lineBreaks.back() && lineWordCount >= 2) {
-      spacing = spareSpace / (lineWordCount - 1);
-    }
-
-    uint16_t xpos = 0;
-    if (style == RIGHT_ALIGN) {
-      xpos = spareSpace - (lineWordCount - 1) * spaceWidth;
-    } else if (style == CENTER_ALIGN) {
-      xpos = (spareSpace - (lineWordCount - 1) * spaceWidth) / 2;
-    }
-
-    for (int i = startWord; i < lineBreak; i++) {
-      wordXpos[i] = xpos;
-      xpos += wordWidths[i] + spacing;
-    }
-
-    std::vector<std::string> lineWords;
-    std::vector<uint16_t> lineXPos;
-    std::vector<uint8_t> lineWordStyles;
-    lineWords.reserve(lineWordCount);
-    lineXPos.reserve(lineWordCount);
-    lineWordStyles.reserve(lineWordCount);
-
-    for (int i = startWord; i < lineBreak; i++) {
-      lineWords.push_back(words[i]);
-      lineXPos.push_back(wordXpos[i]);
-      lineWordStyles.push_back(wordStyles[i]);
-    }
-    const auto textLine = new TextBlock(lineWords, lineXPos, lineWordStyles, style);
-    lines.push_back(textLine);
-    startWord = lineBreak;
-  }
-
-  return lines;
-}
-
-void TextBlock::render(const EpdRenderer& renderer, const int x, const int y) const {
-  for (int i = 0; i < words.size(); i++) {
-    // render the word
-    EpdFontStyle fontStyle = REGULAR;
-    if (wordStyles[i] & BOLD_SPAN && wordStyles[i] & ITALIC_SPAN) {
-      fontStyle = BOLD_ITALIC;
-    } else if (wordStyles[i] & BOLD_SPAN) {
-      fontStyle = BOLD;
-    } else if (wordStyles[i] & ITALIC_SPAN) {
-      fontStyle = ITALIC;
-    }
-    renderer.drawText(x + wordXpos[i], y, words[i].c_str(), 1, fontStyle);
   }
 }
 
@@ -189,11 +37,11 @@ void TextBlock::serialize(std::ostream& os) const {
   serialization::writePod(os, style);
 }
 
-TextBlock* TextBlock::deserialize(std::istream& is) {
+std::unique_ptr<TextBlock> TextBlock::deserialize(std::istream& is) {
   uint32_t wc, xc, sc;
-  std::vector<std::string> words;
+  std::list<std::string> words;
-  std::vector<uint16_t> wordXpos;
+  std::list<uint16_t> wordXpos;
-  std::vector<uint8_t> wordStyles;
+  std::list<EpdFontStyle> wordStyles;
   BLOCK_STYLE style;
 
   // words
@@ -214,5 +62,5 @@ TextBlock* TextBlock::deserialize(std::istream& is) {
   // style
   serialization::readPod(is, style);
 
-  return new TextBlock(words, wordXpos, wordStyles, style);
+  return std::unique_ptr<TextBlock>(new TextBlock(std::move(words), std::move(wordXpos), std::move(wordStyles), style));
 }

lib/Epub/Epub/blocks/TextBlock.h

@@ -1,50 +1,40 @@
 #pragma once
+#include <EpdFontFamily.h>
+
 #include <list>
+#include <memory>
 #include <string>
-#include <vector>
 
 #include "Block.h"
 
-enum SPAN_STYLE : uint8_t {
-  BOLD_SPAN = 1,
-  ITALIC_SPAN = 2,
-};
-
-enum BLOCK_STYLE : uint8_t {
-  JUSTIFIED = 0,
-  LEFT_ALIGN = 1,
-  CENTER_ALIGN = 2,
-  RIGHT_ALIGN = 3,
-};
-
 // represents a block of words in the html document
 class TextBlock final : public Block {
-  // pointer to each word
+ public:
-  std::vector<std::string> words;
+  enum BLOCK_STYLE : uint8_t {
-  // x position of each word
+    JUSTIFIED = 0,
-  std::vector<uint16_t> wordXpos;
+    LEFT_ALIGN = 1,
-  // the styles of each word
+    CENTER_ALIGN = 2,
-  std::vector<uint8_t> wordStyles;
+    RIGHT_ALIGN = 3,
+  };
 
-  // the style of the block - left, center, right aligned
+ private:
+  std::list<std::string> words;
+  std::list<uint16_t> wordXpos;
+  std::list<EpdFontStyle> wordStyles;
   BLOCK_STYLE style;
 
  public:
-  explicit TextBlock(const BLOCK_STYLE style) : style(style) {}
+  explicit TextBlock(std::list<std::string> words, std::list<uint16_t> word_xpos, std::list<EpdFontStyle> word_styles,
-  explicit TextBlock(const std::vector<std::string>& words, const std::vector<uint16_t>& word_xpos,
+                     const BLOCK_STYLE style)
-                     // the styles of each word
+      : words(std::move(words)), wordXpos(std::move(word_xpos)), wordStyles(std::move(word_styles)), style(style) {}
-                     const std::vector<uint8_t>& word_styles, const BLOCK_STYLE style)
-      : words(words), wordXpos(word_xpos), wordStyles(word_styles), style(style) {}
   ~TextBlock() override = default;
-  void addWord(const std::string& word, bool is_bold, bool is_italic);
   void setStyle(const BLOCK_STYLE style) { this->style = style; }
   BLOCK_STYLE getStyle() const { return style; }
   bool isEmpty() override { return words.empty(); }
-  void layout(EpdRenderer& renderer) override {};
+  void layout(GfxRenderer& renderer) override {};
   // given a renderer works out where to break the words into lines
-  std::list<TextBlock*> splitIntoLines(const EpdRenderer& renderer);
+  void render(const GfxRenderer& renderer, int fontId, int x, int y) const;
-  void render(const EpdRenderer& renderer, int x, int y) const;
   BlockType getType() override { return TEXT_BLOCK; }
   void serialize(std::ostream& os) const;
-  static TextBlock* deserialize(std::istream& is);
+  static std::unique_ptr<TextBlock> deserialize(std::istream& is);
 };

lib/Epub/Epub/parsers/ChapterHtmlSlimParser.cpp

@@ -1,11 +1,11 @@
-#include "EpubHtmlParserSlim.h"
+#include "ChapterHtmlSlimParser.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
 #include <HardwareSerial.h>
 #include <expat.h>
 
-#include "Page.h"
+#include "../Page.h"
-#include "htmlEntities.h"
+#include "../htmlEntities.h"
 
 const char* HEADER_TAGS[] = {"h1", "h2", "h3", "h4", "h5", "h6"};
 constexpr int NUM_HEADER_TAGS = sizeof(HEADER_TAGS) / sizeof(HEADER_TAGS[0]);
@@ -38,7 +38,7 @@ bool matches(const char* tag_name, const char* possible_tags[], const int possib
 }
 
 // start a new text block if needed
-void EpubHtmlParserSlim::startNewTextBlock(const BLOCK_STYLE style) {
+void ChapterHtmlSlimParser::startNewTextBlock(const TextBlock::BLOCK_STYLE style) {
   if (currentTextBlock) {
     // already have a text block running and it is empty - just reuse it
     if (currentTextBlock->isEmpty()) {
@@ -46,15 +46,13 @@ void EpubHtmlParserSlim::startNewTextBlock(const BLOCK_STYLE style) {
       return;
     }
 
-    currentTextBlock->finish();
     makePages();
-    delete currentTextBlock;
   }
-  currentTextBlock = new TextBlock(style);
+  currentTextBlock.reset(new ParsedText(style));
 }
 
-void XMLCALL EpubHtmlParserSlim::startElement(void* userData, const XML_Char* name, const XML_Char** atts) {
+void XMLCALL ChapterHtmlSlimParser::startElement(void* userData, const XML_Char* name, const XML_Char** atts) {
-  auto* self = static_cast<EpubHtmlParserSlim*>(userData);
+  auto* self = static_cast<ChapterHtmlSlimParser*>(userData);
   (void)atts;
 
   // Middle of skip
@@ -64,23 +62,7 @@ void XMLCALL EpubHtmlParserSlim::startElement(void* userData, const XML_Char* na
   }
 
   if (matches(name, IMAGE_TAGS, NUM_IMAGE_TAGS)) {
-    // const char* src = element.Attribute("src");
+    // TODO: Start processing image tags
-    // if (src) {
-    //   // don't leave an empty text block in the list
-    //   // const BLOCK_STYLE style = currentTextBlock->get_style();
-    //   if (currentTextBlock->isEmpty()) {
-    //     delete currentTextBlock;
-    //     currentTextBlock = nullptr;
-    //   }
-    //   // TODO: Fix this
-    //   // blocks.push_back(new ImageBlock(m_base_path + src));
-    //   // start a new text block - with the same style as before
-    //   // startNewTextBlock(style);
-    // } else {
-    //   // ESP_LOGE(TAG, "Could not find src attribute");
-    // }
-
-    // start skip
     self->skipUntilDepth = self->depth;
     self->depth += 1;
     return;
@@ -94,13 +76,13 @@ void XMLCALL EpubHtmlParserSlim::startElement(void* userData, const XML_Char* na
   }
 
   if (matches(name, HEADER_TAGS, NUM_HEADER_TAGS)) {
-    self->startNewTextBlock(CENTER_ALIGN);
+    self->startNewTextBlock(TextBlock::CENTER_ALIGN);
     self->boldUntilDepth = min(self->boldUntilDepth, self->depth);
   } else if (matches(name, BLOCK_TAGS, NUM_BLOCK_TAGS)) {
     if (strcmp(name, "br") == 0) {
       self->startNewTextBlock(self->currentTextBlock->getStyle());
     } else {
-      self->startNewTextBlock(JUSTIFIED);
+      self->startNewTextBlock(TextBlock::JUSTIFIED);
     }
   } else if (matches(name, BOLD_TAGS, NUM_BOLD_TAGS)) {
     self->boldUntilDepth = min(self->boldUntilDepth, self->depth);
@@ -111,21 +93,29 @@ void XMLCALL EpubHtmlParserSlim::startElement(void* userData, const XML_Char* na
   self->depth += 1;
 }
 
-void XMLCALL EpubHtmlParserSlim::characterData(void* userData, const XML_Char* s, const int len) {
+void XMLCALL ChapterHtmlSlimParser::characterData(void* userData, const XML_Char* s, const int len) {
-  auto* self = static_cast<EpubHtmlParserSlim*>(userData);
+  auto* self = static_cast<ChapterHtmlSlimParser*>(userData);
 
   // Middle of skip
   if (self->skipUntilDepth < self->depth) {
     return;
   }
 
+  EpdFontStyle fontStyle = REGULAR;
+  if (self->boldUntilDepth < self->depth && self->italicUntilDepth < self->depth) {
+    fontStyle = BOLD_ITALIC;
+  } else if (self->boldUntilDepth < self->depth) {
+    fontStyle = BOLD;
+  } else if (self->italicUntilDepth < self->depth) {
+    fontStyle = ITALIC;
+  }
+
   for (int i = 0; i < len; i++) {
     if (isWhitespace(s[i])) {
       // Currently looking at whitespace, if there's anything in the partWordBuffer, flush it
       if (self->partWordBufferIndex > 0) {
         self->partWordBuffer[self->partWordBufferIndex] = '\0';
-        self->currentTextBlock->addWord(replaceHtmlEntities(self->partWordBuffer), self->boldUntilDepth < self->depth,
+        self->currentTextBlock->addWord(std::move(replaceHtmlEntities(self->partWordBuffer)), fontStyle);
-                                        self->italicUntilDepth < self->depth);
         self->partWordBufferIndex = 0;
       }
       // Skip the whitespace char
@@ -133,10 +123,9 @@ void XMLCALL EpubHtmlParserSlim::characterData(void* userData, const XML_Char* s
     }
 
     // If we're about to run out of space, then cut the word off and start a new one
-    if (self->partWordBufferIndex >= PART_WORD_BUFFER_SIZE - 2) {
+    if (self->partWordBufferIndex >= MAX_WORD_SIZE) {
       self->partWordBuffer[self->partWordBufferIndex] = '\0';
-      self->currentTextBlock->addWord(replaceHtmlEntities(self->partWordBuffer), self->boldUntilDepth < self->depth,
+      self->currentTextBlock->addWord(std::move(replaceHtmlEntities(self->partWordBuffer)), fontStyle);
-                                      self->italicUntilDepth < self->depth);
       self->partWordBufferIndex = 0;
     }
 
@@ -144,8 +133,8 @@ void XMLCALL EpubHtmlParserSlim::characterData(void* userData, const XML_Char* s
   }
 }
 
-void XMLCALL EpubHtmlParserSlim::endElement(void* userData, const XML_Char* name) {
+void XMLCALL ChapterHtmlSlimParser::endElement(void* userData, const XML_Char* name) {
-  auto* self = static_cast<EpubHtmlParserSlim*>(userData);
+  auto* self = static_cast<ChapterHtmlSlimParser*>(userData);
   (void)name;
 
   if (self->partWordBufferIndex > 0) {
@@ -158,9 +147,17 @@ void XMLCALL EpubHtmlParserSlim::endElement(void* userData, const XML_Char* name
         matches(name, BOLD_TAGS, NUM_BOLD_TAGS) || matches(name, ITALIC_TAGS, NUM_ITALIC_TAGS) || self->depth == 1;
 
     if (shouldBreakText) {
+      EpdFontStyle fontStyle = REGULAR;
+      if (self->boldUntilDepth < self->depth && self->italicUntilDepth < self->depth) {
+        fontStyle = BOLD_ITALIC;
+      } else if (self->boldUntilDepth < self->depth) {
+        fontStyle = BOLD;
+      } else if (self->italicUntilDepth < self->depth) {
+        fontStyle = ITALIC;
+      }
+
       self->partWordBuffer[self->partWordBufferIndex] = '\0';
-      self->currentTextBlock->addWord(replaceHtmlEntities(self->partWordBuffer), self->boldUntilDepth < self->depth,
+      self->currentTextBlock->addWord(std::move(replaceHtmlEntities(self->partWordBuffer)), fontStyle);
-                                      self->italicUntilDepth < self->depth);
       self->partWordBufferIndex = 0;
     }
   }
@@ -183,14 +180,14 @@ void XMLCALL EpubHtmlParserSlim::endElement(void* userData, const XML_Char* name
   }
 }
 
-bool EpubHtmlParserSlim::parseAndBuildPages() {
+bool ChapterHtmlSlimParser::parseAndBuildPages() {
-  startNewTextBlock(JUSTIFIED);
+  startNewTextBlock(TextBlock::JUSTIFIED);
 
   const XML_Parser parser = XML_ParserCreate(nullptr);
   int done;
 
   if (!parser) {
-    Serial.println("Couldn't allocate memory for parser");
+    Serial.printf("[%lu] [EHP] Couldn't allocate memory for parser\n", millis());
     return false;
   }
 
@@ -200,7 +197,7 @@ bool EpubHtmlParserSlim::parseAndBuildPages() {
 
   FILE* file = fopen(filepath, "r");
   if (!file) {
-    Serial.printf("Couldn't open file %s\n", filepath);
+    Serial.printf("[%lu] [EHP] Couldn't open file %s\n", millis(), filepath);
     XML_ParserFree(parser);
     return false;
   }
@@ -208,7 +205,7 @@ bool EpubHtmlParserSlim::parseAndBuildPages() {
   do {
     void* const buf = XML_GetBuffer(parser, 1024);
     if (!buf) {
-      Serial.println("Couldn't allocate memory for buffer");
+      Serial.printf("[%lu] [EHP] Couldn't allocate memory for buffer\n", millis());
       XML_ParserFree(parser);
       fclose(file);
       return false;
@@ -217,7 +214,7 @@ bool EpubHtmlParserSlim::parseAndBuildPages() {
     const size_t len = fread(buf, 1, 1024, file);
 
     if (ferror(file)) {
-      Serial.println("Read error");
+      Serial.printf("[%lu] [EHP] File read error\n", millis());
       XML_ParserFree(parser);
       fclose(file);
       return false;
@@ -226,7 +223,7 @@ bool EpubHtmlParserSlim::parseAndBuildPages() {
     done = feof(file);
 
     if (XML_ParseBuffer(parser, static_cast<int>(len), done) == XML_STATUS_ERROR) {
-      Serial.printf("Parse error at line %lu:\n%s\n", XML_GetCurrentLineNumber(parser),
+      Serial.printf("[%lu] [EHP] Parse error at line %lu:\n%s\n", millis(), XML_GetCurrentLineNumber(parser),
                     XML_ErrorString(XML_GetErrorCode(parser)));
       XML_ParserFree(parser);
       fclose(file);
@@ -240,54 +237,43 @@ bool EpubHtmlParserSlim::parseAndBuildPages() {
   // Process last page if there is still text
   if (currentTextBlock) {
     makePages();
-    completePageFn(currentPage);
+    completePageFn(std::move(currentPage));
-    currentPage = nullptr;
+    currentPage.reset();
-    delete currentTextBlock;
+    currentTextBlock.reset();
-    currentTextBlock = nullptr;
   }
 
   return true;
 }
 
-void EpubHtmlParserSlim::makePages() {
+void ChapterHtmlSlimParser::addLineToPage(std::shared_ptr<TextBlock> line) {
+  const int lineHeight = renderer.getLineHeight(fontId) * lineCompression;
+  const int pageHeight = GfxRenderer::getScreenHeight() - marginTop - marginBottom;
+
+  if (currentPageNextY + lineHeight > pageHeight) {
+    completePageFn(std::move(currentPage));
+    currentPage.reset(new Page());
+    currentPageNextY = marginTop;
+  }
+
+  currentPage->elements.push_back(std::make_shared<PageLine>(line, marginLeft, currentPageNextY));
+  currentPageNextY += lineHeight;
+}
+
+void ChapterHtmlSlimParser::makePages() {
   if (!currentTextBlock) {
-    Serial.println("!! No text block to make pages for !!");
+    Serial.printf("[%lu] [EHP] !! No text block to make pages for !!\n", millis());
     return;
   }
 
   if (!currentPage) {
-    currentPage = new Page();
+    currentPage.reset(new Page());
+    currentPageNextY = marginTop;
   }
 
-  const int lineHeight = renderer.getLineHeight();
+  const int lineHeight = renderer.getLineHeight(fontId) * lineCompression;
-  const int pageHeight = renderer.getPageHeight();
+  currentTextBlock->layoutAndExtractLines(
-
+      renderer, fontId, marginLeft + marginRight,
-  // Long running task, make sure to let other things happen
+      [this](const std::shared_ptr<TextBlock>& textBlock) { addLineToPage(textBlock); });
-  vTaskDelay(1);
+  // Extra paragrpah spacing
-
+  currentPageNextY += lineHeight / 2;
-  if (currentTextBlock->getType() == TEXT_BLOCK) {
-    const auto lines = currentTextBlock->splitIntoLines(renderer);
-
-    for (const auto line : lines) {
-      if (currentPage->nextY + lineHeight > pageHeight) {
-        completePageFn(currentPage);
-        currentPage = new Page();
-      }
-
-      currentPage->elements.push_back(new PageLine(line, currentPage->nextY));
-      currentPage->nextY += lineHeight;
-    }
-    // add some extra line between blocks
-    currentPage->nextY += lineHeight / 2;
-  }
-  // TODO: Image block support
-  // if (block->getType() == BlockType::IMAGE_BLOCK) {
-  //   ImageBlock *imageBlock = (ImageBlock *)block;
-  //   if (y + imageBlock->height > page_height) {
-  //     pages.push_back(new Page());
-  //     y = 0;
-  //   }
-  //   pages.back()->elements.push_back(new PageImage(imageBlock, y));
-  //   y += imageBlock->height;
-  // }
 }

lib/Epub/Epub/parsers/ChapterHtmlSlimParser.h

@@ -0,0 +1,63 @@
+#pragma once
+
+#include <expat.h>
+
+#include <climits>
+#include <functional>
+#include <memory>
+
+#include "../ParsedText.h"
+#include "../blocks/TextBlock.h"
+
+class Page;
+class GfxRenderer;
+
+#define MAX_WORD_SIZE 200
+
+class ChapterHtmlSlimParser {
+  const char* filepath;
+  GfxRenderer& renderer;
+  std::function<void(std::unique_ptr<Page>)> completePageFn;
+  int depth = 0;
+  int skipUntilDepth = INT_MAX;
+  int boldUntilDepth = INT_MAX;
+  int italicUntilDepth = INT_MAX;
+  // buffer for building up words from characters, will auto break if longer than this
+  // leave one char at end for null pointer
+  char partWordBuffer[MAX_WORD_SIZE + 1] = {};
+  int partWordBufferIndex = 0;
+  std::unique_ptr<ParsedText> currentTextBlock = nullptr;
+  std::unique_ptr<Page> currentPage = nullptr;
+  int16_t currentPageNextY = 0;
+  int fontId;
+  float lineCompression;
+  int marginTop;
+  int marginRight;
+  int marginBottom;
+  int marginLeft;
+
+  void startNewTextBlock(TextBlock::BLOCK_STYLE style);
+  void makePages();
+  // XML callbacks
+  static void XMLCALL startElement(void* userData, const XML_Char* name, const XML_Char** atts);
+  static void XMLCALL characterData(void* userData, const XML_Char* s, int len);
+  static void XMLCALL endElement(void* userData, const XML_Char* name);
+
+ public:
+  explicit ChapterHtmlSlimParser(const char* filepath, GfxRenderer& renderer, const int fontId,
+                                 const float lineCompression, const int marginTop, const int marginRight,
+                                 const int marginBottom, const int marginLeft,
+                                 const std::function<void(std::unique_ptr<Page>)>& completePageFn)
+      : filepath(filepath),
+        renderer(renderer),
+        fontId(fontId),
+        lineCompression(lineCompression),
+        marginTop(marginTop),
+        marginRight(marginRight),
+        marginBottom(marginBottom),
+        marginLeft(marginLeft),
+        completePageFn(completePageFn) {}
+  ~ChapterHtmlSlimParser() = default;
+  bool parseAndBuildPages();
+  void addLineToPage(std::shared_ptr<TextBlock> line);
+};

lib/Epub/Epub/parsers/ContainerParser.cpp

@@ -0,0 +1,96 @@
+#include "ContainerParser.h"
+
+#include <HardwareSerial.h>
+
+bool ContainerParser::setup() {
+  parser = XML_ParserCreate(nullptr);
+  if (!parser) {
+    Serial.printf("[%lu] [CTR] Couldn't allocate memory for parser\n", millis());
+    return false;
+  }
+
+  XML_SetUserData(parser, this);
+  XML_SetElementHandler(parser, startElement, endElement);
+  return true;
+}
+
+bool ContainerParser::teardown() {
+  if (parser) {
+    XML_ParserFree(parser);
+    parser = nullptr;
+  }
+  return true;
+}
+
+size_t ContainerParser::write(const uint8_t data) { return write(&data, 1); }
+
+size_t ContainerParser::write(const uint8_t* buffer, const size_t size) {
+  if (!parser) return 0;
+
+  const uint8_t* currentBufferPos = buffer;
+  auto remainingInBuffer = size;
+
+  while (remainingInBuffer > 0) {
+    void* const buf = XML_GetBuffer(parser, 1024);
+    if (!buf) {
+      Serial.printf("[%lu] [CTR] Couldn't allocate buffer\n", millis());
+      return 0;
+    }
+
+    const auto toRead = remainingInBuffer < 1024 ? remainingInBuffer : 1024;
+    memcpy(buf, currentBufferPos, toRead);
+
+    if (XML_ParseBuffer(parser, static_cast<int>(toRead), remainingSize == toRead) == XML_STATUS_ERROR) {
+      Serial.printf("[%lu] [CTR] Parse error: %s\n", millis(), XML_ErrorString(XML_GetErrorCode(parser)));
+      return 0;
+    }
+
+    currentBufferPos += toRead;
+    remainingInBuffer -= toRead;
+    remainingSize -= toRead;
+  }
+  return size;
+}
+
+void XMLCALL ContainerParser::startElement(void* userData, const XML_Char* name, const XML_Char** atts) {
+  auto* self = static_cast<ContainerParser*>(userData);
+
+  // Simple state tracking to ensure we are looking at the valid schema structure
+  if (self->state == START && strcmp(name, "container") == 0) {
+    self->state = IN_CONTAINER;
+    return;
+  }
+
+  if (self->state == IN_CONTAINER && strcmp(name, "rootfiles") == 0) {
+    self->state = IN_ROOTFILES;
+    return;
+  }
+
+  if (self->state == IN_ROOTFILES && strcmp(name, "rootfile") == 0) {
+    const char* mediaType = nullptr;
+    const char* path = nullptr;
+
+    for (int i = 0; atts[i]; i += 2) {
+      if (strcmp(atts[i], "media-type") == 0) {
+        mediaType = atts[i + 1];
+      } else if (strcmp(atts[i], "full-path") == 0) {
+        path = atts[i + 1];
+      }
+    }
+
+    // Check if this is the standard OEBPS package
+    if (mediaType && path && strcmp(mediaType, "application/oebps-package+xml") == 0) {
+      self->fullPath = path;
+    }
+  }
+}
+
+void XMLCALL ContainerParser::endElement(void* userData, const XML_Char* name) {
+  auto* self = static_cast<ContainerParser*>(userData);
+
+  if (self->state == IN_ROOTFILES && strcmp(name, "rootfiles") == 0) {
+    self->state = IN_CONTAINER;
+  } else if (self->state == IN_CONTAINER && strcmp(name, "container") == 0) {
+    self->state = START;
+  }
+}

lib/Epub/Epub/parsers/ContainerParser.h

@@ -0,0 +1,32 @@
+#pragma once
+#include <Print.h>
+
+#include <string>
+
+#include "expat.h"
+
+class ContainerParser final : public Print {
+  enum ParserState {
+    START,
+    IN_CONTAINER,
+    IN_ROOTFILES,
+  };
+
+  size_t remainingSize;
+  XML_Parser parser = nullptr;
+  ParserState state = START;
+
+  static void startElement(void* userData, const XML_Char* name, const XML_Char** atts);
+  static void endElement(void* userData, const XML_Char* name);
+
+ public:
+  std::string fullPath;
+
+  explicit ContainerParser(const size_t xmlSize) : remainingSize(xmlSize) {}
+
+  bool setup();
+  bool teardown();
+
+  size_t write(uint8_t) override;
+  size_t write(const uint8_t* buffer, size_t size) override;
+};

lib/Epub/Epub/parsers/ContentOpfParser.cpp

@@ -0,0 +1,161 @@
+#include "ContentOpfParser.h"
+
+#include <HardwareSerial.h>
+#include <ZipFile.h>
+
+bool ContentOpfParser::setup() {
+  parser = XML_ParserCreate(nullptr);
+  if (!parser) {
+    Serial.printf("[%lu] [COF] Couldn't allocate memory for parser\n", millis());
+    return false;
+  }
+
+  XML_SetUserData(parser, this);
+  XML_SetElementHandler(parser, startElement, endElement);
+  XML_SetCharacterDataHandler(parser, characterData);
+  return true;
+}
+
+bool ContentOpfParser::teardown() {
+  if (parser) {
+    XML_ParserFree(parser);
+    parser = nullptr;
+  }
+  return true;
+}
+
+size_t ContentOpfParser::write(const uint8_t data) { return write(&data, 1); }
+
+size_t ContentOpfParser::write(const uint8_t* buffer, const size_t size) {
+  if (!parser) return 0;
+
+  const uint8_t* currentBufferPos = buffer;
+  auto remainingInBuffer = size;
+
+  while (remainingInBuffer > 0) {
+    void* const buf = XML_GetBuffer(parser, 1024);
+
+    if (!buf) {
+      Serial.printf("[%lu] [COF] Couldn't allocate memory for buffer\n", millis());
+      XML_ParserFree(parser);
+      parser = nullptr;
+      return 0;
+    }
+
+    const auto toRead = remainingInBuffer < 1024 ? remainingInBuffer : 1024;
+    memcpy(buf, currentBufferPos, toRead);
+
+    if (XML_ParseBuffer(parser, static_cast<int>(toRead), remainingSize == toRead) == XML_STATUS_ERROR) {
+      Serial.printf("[%lu] [COF] Parse error at line %lu: %s\n", millis(), XML_GetCurrentLineNumber(parser),
+                    XML_ErrorString(XML_GetErrorCode(parser)));
+      XML_ParserFree(parser);
+      parser = nullptr;
+      return 0;
+    }
+
+    currentBufferPos += toRead;
+    remainingInBuffer -= toRead;
+    remainingSize -= toRead;
+  }
+
+  return size;
+}
+
+void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name, const XML_Char** atts) {
+  auto* self = static_cast<ContentOpfParser*>(userData);
+  (void)atts;
+
+  if (self->state == START && (strcmp(name, "package") == 0 || strcmp(name, "opf:package") == 0)) {
+    self->state = IN_PACKAGE;
+    return;
+  }
+
+  if (self->state == IN_PACKAGE && (strcmp(name, "metadata") == 0 || strcmp(name, "opf:metadata") == 0)) {
+    self->state = IN_METADATA;
+    return;
+  }
+
+  if (self->state == IN_METADATA && strcmp(name, "dc:title") == 0) {
+    self->state = IN_BOOK_TITLE;
+    return;
+  }
+
+  if (self->state == IN_PACKAGE && (strcmp(name, "manifest") == 0 || strcmp(name, "opf:manifest") == 0)) {
+    self->state = IN_MANIFEST;
+    return;
+  }
+
+  if (self->state == IN_PACKAGE && (strcmp(name, "spine") == 0 || strcmp(name, "opf:spine") == 0)) {
+    self->state = IN_SPINE;
+    return;
+  }
+
+  // TODO: Support book cover
+  // if (self->state == IN_METADATA && (strcmp(name, "meta") == 0 || strcmp(name, "opf:meta") == 0)) {
+  // }
+
+  if (self->state == IN_MANIFEST && (strcmp(name, "item") == 0 || strcmp(name, "opf:item") == 0)) {
+    std::string itemId;
+    std::string href;
+
+    for (int i = 0; atts[i]; i += 2) {
+      if (strcmp(atts[i], "id") == 0) {
+        itemId = atts[i + 1];
+      } else if (strcmp(atts[i], "href") == 0) {
+        href = self->baseContentPath + atts[i + 1];
+      }
+    }
+
+    self->items[itemId] = href;
+    return;
+  }
+
+  if (self->state == IN_SPINE && (strcmp(name, "itemref") == 0 || strcmp(name, "opf:itemref") == 0)) {
+    for (int i = 0; atts[i]; i += 2) {
+      if (strcmp(atts[i], "idref") == 0) {
+        self->spineRefs.emplace_back(atts[i + 1]);
+        break;
+      }
+    }
+    return;
+  }
+}
+
+void XMLCALL ContentOpfParser::characterData(void* userData, const XML_Char* s, const int len) {
+  auto* self = static_cast<ContentOpfParser*>(userData);
+
+  if (self->state == IN_BOOK_TITLE) {
+    self->title.append(s, len);
+    return;
+  }
+}
+
+void XMLCALL ContentOpfParser::endElement(void* userData, const XML_Char* name) {
+  auto* self = static_cast<ContentOpfParser*>(userData);
+  (void)name;
+
+  if (self->state == IN_SPINE && (strcmp(name, "spine") == 0 || strcmp(name, "opf:spine") == 0)) {
+    self->state = IN_PACKAGE;
+    return;
+  }
+
+  if (self->state == IN_MANIFEST && (strcmp(name, "manifest") == 0 || strcmp(name, "opf:manifest") == 0)) {
+    self->state = IN_PACKAGE;
+    return;
+  }
+
+  if (self->state == IN_BOOK_TITLE && strcmp(name, "dc:title") == 0) {
+    self->state = IN_METADATA;
+    return;
+  }
+
+  if (self->state == IN_METADATA && (strcmp(name, "metadata") == 0 || strcmp(name, "opf:metadata") == 0)) {
+    self->state = IN_PACKAGE;
+    return;
+  }
+
+  if (self->state == IN_PACKAGE && (strcmp(name, "package") == 0 || strcmp(name, "opf:package") == 0)) {
+    self->state = START;
+    return;
+  }
+}

lib/Epub/Epub/parsers/ContentOpfParser.h

@@ -0,0 +1,42 @@
+#pragma once
+#include <Print.h>
+
+#include <map>
+
+#include "Epub.h"
+#include "expat.h"
+
+class ContentOpfParser final : public Print {
+  enum ParserState {
+    START,
+    IN_PACKAGE,
+    IN_METADATA,
+    IN_BOOK_TITLE,
+    IN_MANIFEST,
+    IN_SPINE,
+  };
+
+  const std::string& baseContentPath;
+  size_t remainingSize;
+  XML_Parser parser = nullptr;
+  ParserState state = START;
+
+  static void startElement(void* userData, const XML_Char* name, const XML_Char** atts);
+  static void characterData(void* userData, const XML_Char* s, int len);
+  static void endElement(void* userData, const XML_Char* name);
+
+ public:
+  std::string title;
+  std::string tocNcxPath;
+  std::map<std::string, std::string> items;
+  std::vector<std::string> spineRefs;
+
+  explicit ContentOpfParser(const std::string& baseContentPath, const size_t xmlSize)
+      : baseContentPath(baseContentPath), remainingSize(xmlSize) {}
+
+  bool setup();
+  bool teardown();
+
+  size_t write(uint8_t) override;
+  size_t write(const uint8_t* buffer, size_t size) override;
+};

lib/Epub/Epub/parsers/TocNcxParser.cpp

@@ -0,0 +1,165 @@
+#include "TocNcxParser.h"
+
+#include <HardwareSerial.h>
+
+bool TocNcxParser::setup() {
+  parser = XML_ParserCreate(nullptr);
+  if (!parser) {
+    Serial.printf("[%lu] [TOC] Couldn't allocate memory for parser\n", millis());
+    return false;
+  }
+
+  XML_SetUserData(parser, this);
+  XML_SetElementHandler(parser, startElement, endElement);
+  XML_SetCharacterDataHandler(parser, characterData);
+  return true;
+}
+
+bool TocNcxParser::teardown() {
+  if (parser) {
+    XML_ParserFree(parser);
+    parser = nullptr;
+  }
+  return true;
+}
+
+size_t TocNcxParser::write(const uint8_t data) { return write(&data, 1); }
+
+size_t TocNcxParser::write(const uint8_t* buffer, const size_t size) {
+  if (!parser) return 0;
+
+  const uint8_t* currentBufferPos = buffer;
+  auto remainingInBuffer = size;
+
+  while (remainingInBuffer > 0) {
+    void* const buf = XML_GetBuffer(parser, 1024);
+    if (!buf) {
+      Serial.printf("[%lu] [TOC] Couldn't allocate memory for buffer\n", millis());
+      return 0;
+    }
+
+    const auto toRead = remainingInBuffer < 1024 ? remainingInBuffer : 1024;
+    memcpy(buf, currentBufferPos, toRead);
+
+    if (XML_ParseBuffer(parser, static_cast<int>(toRead), remainingSize == toRead) == XML_STATUS_ERROR) {
+      Serial.printf("[%lu] [TOC] Parse error at line %lu: %s\n", millis(), XML_GetCurrentLineNumber(parser),
+                    XML_ErrorString(XML_GetErrorCode(parser)));
+      return 0;
+    }
+
+    currentBufferPos += toRead;
+    remainingInBuffer -= toRead;
+    remainingSize -= toRead;
+  }
+  return size;
+}
+
+void XMLCALL TocNcxParser::startElement(void* userData, const XML_Char* name, const XML_Char** atts) {
+  // NOTE: We rely on navPoint label and content coming before any nested navPoints, this will be fine:
+  // <navPoint>
+  //   <navLabel><text>Chapter 1</text></navLabel>
+  //   <content src="ch1.html"/>
+  //   <navPoint> ...nested... </navPoint>
+  // </navPoint>
+  //
+  // This will NOT:
+  // <navPoint>
+  //   <navPoint> ...nested... </navPoint>
+  //   <navLabel><text>Chapter 1</text></navLabel>
+  //   <content src="ch1.html"/>
+  // </navPoint>
+
+  auto* self = static_cast<TocNcxParser*>(userData);
+
+  if (self->state == START && strcmp(name, "ncx") == 0) {
+    self->state = IN_NCX;
+    return;
+  }
+
+  if (self->state == IN_NCX && strcmp(name, "navMap") == 0) {
+    self->state = IN_NAV_MAP;
+    return;
+  }
+
+  // Handles both top-level and nested navPoints
+  if ((self->state == IN_NAV_MAP || self->state == IN_NAV_POINT) && strcmp(name, "navPoint") == 0) {
+    self->state = IN_NAV_POINT;
+    self->currentDepth++;
+
+    self->currentLabel.clear();
+    self->currentSrc.clear();
+    return;
+  }
+
+  if (self->state == IN_NAV_POINT && strcmp(name, "navLabel") == 0) {
+    self->state = IN_NAV_LABEL;
+    return;
+  }
+
+  if (self->state == IN_NAV_LABEL && strcmp(name, "text") == 0) {
+    self->state = IN_NAV_LABEL_TEXT;
+    return;
+  }
+
+  if (self->state == IN_NAV_POINT && strcmp(name, "content") == 0) {
+    for (int i = 0; atts[i]; i += 2) {
+      if (strcmp(atts[i], "src") == 0) {
+        self->currentSrc = atts[i + 1];
+        break;
+      }
+    }
+    return;
+  }
+}
+
+void XMLCALL TocNcxParser::characterData(void* userData, const XML_Char* s, const int len) {
+  auto* self = static_cast<TocNcxParser*>(userData);
+  if (self->state == IN_NAV_LABEL_TEXT) {
+    self->currentLabel.append(s, len);
+  }
+}
+
+void XMLCALL TocNcxParser::endElement(void* userData, const XML_Char* name) {
+  auto* self = static_cast<TocNcxParser*>(userData);
+
+  if (self->state == IN_NAV_LABEL_TEXT && strcmp(name, "text") == 0) {
+    self->state = IN_NAV_LABEL;
+    return;
+  }
+
+  if (self->state == IN_NAV_LABEL && strcmp(name, "navLabel") == 0) {
+    self->state = IN_NAV_POINT;
+    return;
+  }
+
+  if (self->state == IN_NAV_POINT && strcmp(name, "navPoint") == 0) {
+    self->currentDepth--;
+    if (self->currentDepth == 0) {
+      self->state = IN_NAV_MAP;
+    }
+    return;
+  }
+
+  if (self->state == IN_NAV_POINT && strcmp(name, "content") == 0) {
+    // At this point (end of content tag), we likely have both Label (from previous tags) and Src.
+    // This is the safest place to push the data, assuming <navLabel> always comes before <content>.
+    // NCX spec says navLabel comes before content.
+    if (!self->currentLabel.empty() && !self->currentSrc.empty()) {
+      std::string href = self->baseContentPath + self->currentSrc;
+      std::string anchor;
+
+      const size_t pos = href.find('#');
+      if (pos != std::string::npos) {
+        anchor = href.substr(pos + 1);
+        href = href.substr(0, pos);
+      }
+
+      // Push to vector
+      self->toc.emplace_back(self->currentLabel, href, anchor, self->currentDepth);
+
+      // Clear them so we don't re-add them if there are weird XML structures
+      self->currentLabel.clear();
+      self->currentSrc.clear();
+    }
+  }
+}

lib/Epub/Epub/parsers/TocNcxParser.h

@@ -0,0 +1,37 @@
+#pragma once
+#include <Print.h>
+
+#include <string>
+#include <vector>
+
+#include "Epub/EpubTocEntry.h"
+#include "expat.h"
+
+class TocNcxParser final : public Print {
+  enum ParserState { START, IN_NCX, IN_NAV_MAP, IN_NAV_POINT, IN_NAV_LABEL, IN_NAV_LABEL_TEXT, IN_CONTENT };
+
+  const std::string& baseContentPath;
+  size_t remainingSize;
+  XML_Parser parser = nullptr;
+  ParserState state = START;
+
+  std::string currentLabel;
+  std::string currentSrc;
+  size_t currentDepth = 0;
+
+  static void startElement(void* userData, const XML_Char* name, const XML_Char** atts);
+  static void characterData(void* userData, const XML_Char* s, int len);
+  static void endElement(void* userData, const XML_Char* name);
+
+ public:
+  std::vector<EpubTocEntry> toc;
+
+  explicit TocNcxParser(const std::string& baseContentPath, const size_t xmlSize)
+      : baseContentPath(baseContentPath), remainingSize(xmlSize) {}
+
+  bool setup();
+  bool teardown();
+
+  size_t write(uint8_t) override;
+  size_t write(const uint8_t* buffer, size_t size) override;
+};

lib/GfxRenderer/GfxRenderer.cpp

@@ -0,0 +1,233 @@
+#include "GfxRenderer.h"
+
+#include <Utf8.h>
+
+void GfxRenderer::insertFont(const int fontId, EpdFontFamily font) { fontMap.insert({fontId, font}); }
+
+void GfxRenderer::drawPixel(const int x, const int y, const bool state) const {
+  uint8_t* frameBuffer = einkDisplay.getFrameBuffer();
+
+  // Early return if no framebuffer is set
+  if (!frameBuffer) {
+    Serial.printf("[%lu] [GFX] !! No framebuffer\n", millis());
+    return;
+  }
+
+  // Rotate coordinates: portrait (480x800) -> landscape (800x480)
+  // Rotation: 90 degrees clockwise
+  const int rotatedX = y;
+  const int rotatedY = EInkDisplay::DISPLAY_HEIGHT - 1 - x;
+
+  // Bounds checking (portrait: 480x800)
+  if (rotatedX < 0 || rotatedX >= EInkDisplay::DISPLAY_WIDTH || rotatedY < 0 ||
+      rotatedY >= EInkDisplay::DISPLAY_HEIGHT) {
+    Serial.printf("[%lu] [GFX] !! Outside range (%d, %d)\n", millis(), x, y);
+    return;
+  }
+
+  // Calculate byte position and bit position
+  const uint16_t byteIndex = rotatedY * EInkDisplay::DISPLAY_WIDTH_BYTES + (rotatedX / 8);
+  const uint8_t bitPosition = 7 - (rotatedX % 8);  // MSB first
+
+  if (state) {
+    frameBuffer[byteIndex] &= ~(1 << bitPosition);  // Clear bit
+  } else {
+    frameBuffer[byteIndex] |= 1 << bitPosition;  // Set bit
+  }
+}
+
+int GfxRenderer::getTextWidth(const int fontId, const char* text, const EpdFontStyle style) const {
+  if (fontMap.count(fontId) == 0) {
+    Serial.printf("[%lu] [GFX] Font %d not found\n", millis(), fontId);
+    return 0;
+  }
+
+  int w = 0, h = 0;
+  fontMap.at(fontId).getTextDimensions(text, &w, &h, style);
+  return w;
+}
+
+void GfxRenderer::drawCenteredText(const int fontId, const int y, const char* text, const bool black,
+                                   const EpdFontStyle style) const {
+  const int x = (getScreenWidth() - getTextWidth(fontId, text, style)) / 2;
+  drawText(fontId, x, y, text, black, style);
+}
+
+void GfxRenderer::drawText(const int fontId, const int x, const int y, const char* text, const bool black,
+                           const EpdFontStyle style) const {
+  const int yPos = y + getLineHeight(fontId);
+  int xpos = x;
+
+  // cannot draw a NULL / empty string
+  if (text == nullptr || *text == '\0') {
+    return;
+  }
+
+  if (fontMap.count(fontId) == 0) {
+    Serial.printf("[%lu] [GFX] Font %d not found\n", millis(), fontId);
+    return;
+  }
+  const auto font = fontMap.at(fontId);
+
+  // no printable characters
+  if (!font.hasPrintableChars(text, style)) {
+    return;
+  }
+
+  uint32_t cp;
+  while ((cp = utf8NextCodepoint(reinterpret_cast<const uint8_t**>(&text)))) {
+    renderChar(font, cp, &xpos, &yPos, black, style);
+  }
+}
+
+void GfxRenderer::drawLine(int x1, int y1, int x2, int y2, const bool state) const {
+  if (x1 == x2) {
+    if (y2 < y1) {
+      std::swap(y1, y2);
+    }
+    for (int y = y1; y <= y2; y++) {
+      drawPixel(x1, y, state);
+    }
+  } else if (y1 == y2) {
+    if (x2 < x1) {
+      std::swap(x1, x2);
+    }
+    for (int x = x1; x <= x2; x++) {
+      drawPixel(x, y1, state);
+    }
+  } else {
+    // TODO: Implement
+    Serial.printf("[%lu] [GFX] Line drawing not supported\n", millis());
+  }
+}
+
+void GfxRenderer::drawRect(const int x, const int y, const int width, const int height, const bool state) const {
+  drawLine(x, y, x + width - 1, y, state);
+  drawLine(x + width - 1, y, x + width - 1, y + height - 1, state);
+  drawLine(x + width - 1, y + height - 1, x, y + height - 1, state);
+  drawLine(x, y, x, y + height - 1, state);
+}
+
+void GfxRenderer::fillRect(const int x, const int y, const int width, const int height, const bool state) const {
+  for (int fillY = y; fillY < y + height; fillY++) {
+    drawLine(x, fillY, x + width - 1, fillY, state);
+  }
+}
+
+void GfxRenderer::drawImage(const uint8_t bitmap[], const int x, const int y, const int width, const int height) const {
+  // Flip X and Y for portrait mode
+  einkDisplay.drawImage(bitmap, y, x, height, width);
+}
+
+void GfxRenderer::clearScreen(const uint8_t color) const { einkDisplay.clearScreen(color); }
+
+void GfxRenderer::invertScreen() const {
+  uint8_t* buffer = einkDisplay.getFrameBuffer();
+  for (int i = 0; i < EInkDisplay::BUFFER_SIZE; i++) {
+    buffer[i] = ~buffer[i];
+  }
+}
+
+void GfxRenderer::displayBuffer(const EInkDisplay::RefreshMode refreshMode) const {
+  einkDisplay.displayBuffer(refreshMode);
+}
+
+// TODO: Support partial window update
+// void GfxRenderer::flushArea(const int x, const int y, const int width, const int height) const {
+//   const int rotatedX = y;
+//   const int rotatedY = EInkDisplay::DISPLAY_HEIGHT - 1 - x;
+//
+//   einkDisplay.displayBuffer(EInkDisplay::FAST_REFRESH, rotatedX, rotatedY, height, width);
+// }
+
+// Note: Internal driver treats screen in command orientation, this library treats in portrait orientation
+int GfxRenderer::getScreenWidth() { return EInkDisplay::DISPLAY_HEIGHT; }
+int GfxRenderer::getScreenHeight() { return EInkDisplay::DISPLAY_WIDTH; }
+
+int GfxRenderer::getSpaceWidth(const int fontId) const {
+  if (fontMap.count(fontId) == 0) {
+    Serial.printf("[%lu] [GFX] Font %d not found\n", millis(), fontId);
+    return 0;
+  }
+
+  return fontMap.at(fontId).getGlyph(' ', REGULAR)->advanceX;
+}
+
+int GfxRenderer::getLineHeight(const int fontId) const {
+  if (fontMap.count(fontId) == 0) {
+    Serial.printf("[%lu] [GFX] Font %d not found\n", millis(), fontId);
+    return 0;
+  }
+
+  return fontMap.at(fontId).getData(REGULAR)->advanceY;
+}
+
+uint8_t* GfxRenderer::getFrameBuffer() const { return einkDisplay.getFrameBuffer(); }
+
+void GfxRenderer::swapBuffers() const { einkDisplay.swapBuffers(); }
+
+void GfxRenderer::grayscaleRevert() const { einkDisplay.grayscaleRevert(); }
+
+void GfxRenderer::copyGrayscaleLsbBuffers() const { einkDisplay.copyGrayscaleLsbBuffers(einkDisplay.getFrameBuffer()); }
+
+void GfxRenderer::copyGrayscaleMsbBuffers() const { einkDisplay.copyGrayscaleMsbBuffers(einkDisplay.getFrameBuffer()); }
+
+void GfxRenderer::displayGrayBuffer() const { einkDisplay.displayGrayBuffer(); }
+
+void GfxRenderer::renderChar(const EpdFontFamily& fontFamily, const uint32_t cp, int* x, const int* y,
+                             const bool pixelState, const EpdFontStyle style) const {
+  const EpdGlyph* glyph = fontFamily.getGlyph(cp, style);
+  if (!glyph) {
+    // TODO: Replace with fallback glyph property?
+    glyph = fontFamily.getGlyph('?', style);
+  }
+
+  // no glyph?
+  if (!glyph) {
+    Serial.printf("[%lu] [GFX] No glyph for codepoint %d\n", millis(), cp);
+    return;
+  }
+
+  const int is2Bit = fontFamily.getData(style)->is2Bit;
+  const uint32_t offset = glyph->dataOffset;
+  const uint8_t width = glyph->width;
+  const uint8_t height = glyph->height;
+  const int left = glyph->left;
+
+  const uint8_t* bitmap = nullptr;
+  bitmap = &fontFamily.getData(style)->bitmap[offset];
+
+  if (bitmap != nullptr) {
+    for (int glyphY = 0; glyphY < height; glyphY++) {
+      const int screenY = *y - glyph->top + glyphY;
+      for (int glyphX = 0; glyphX < width; glyphX++) {
+        const int pixelPosition = glyphY * width + glyphX;
+        const int screenX = *x + left + glyphX;
+
+        if (is2Bit) {
+          const uint8_t byte = bitmap[pixelPosition / 4];
+          const uint8_t bit_index = (3 - pixelPosition % 4) * 2;
+
+          const uint8_t val = (byte >> bit_index) & 0x3;
+          if (fontRenderMode == BW && val > 0) {
+            drawPixel(screenX, screenY, pixelState);
+          } else if (fontRenderMode == GRAYSCALE_MSB && val == 1) {
+            // TODO: Not sure how this anti-aliasing goes on black backgrounds
+            drawPixel(screenX, screenY, false);
+          } else if (fontRenderMode == GRAYSCALE_LSB && val == 2) {
+            drawPixel(screenX, screenY, false);
+          }
+        } else {
+          const uint8_t byte = bitmap[pixelPosition / 8];
+          const uint8_t bit_index = 7 - (pixelPosition % 8);
+
+          if ((byte >> bit_index) & 1) {
+            drawPixel(screenX, screenY, pixelState);
+          }
+        }
+      }
+    }
+  }
+
+  *x += glyph->advanceX;
+}

lib/GfxRenderer/GfxRenderer.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <EInkDisplay.h>
+#include <EpdFontFamily.h>
+
+#include <map>
+
+class GfxRenderer {
+ public:
+  enum FontRenderMode { BW, GRAYSCALE_LSB, GRAYSCALE_MSB };
+
+ private:
+  EInkDisplay& einkDisplay;
+  FontRenderMode fontRenderMode;
+  std::map<int, EpdFontFamily> fontMap;
+  void renderChar(const EpdFontFamily& fontFamily, uint32_t cp, int* x, const int* y, bool pixelState,
+                  EpdFontStyle style) const;
+
+ public:
+  explicit GfxRenderer(EInkDisplay& einkDisplay) : einkDisplay(einkDisplay), fontRenderMode(BW) {}
+  ~GfxRenderer() = default;
+
+  // Setup
+  void insertFont(int fontId, EpdFontFamily font);
+
+  // Screen ops
+  static int getScreenWidth();
+  static int getScreenHeight();
+  void displayBuffer(EInkDisplay::RefreshMode refreshMode = EInkDisplay::FAST_REFRESH) const;
+  void invertScreen() const;
+  void clearScreen(uint8_t color = 0xFF) const;
+
+  // Drawing
+  void drawPixel(int x, int y, bool state = true) const;
+  void drawLine(int x1, int y1, int x2, int y2, bool state = true) const;
+  void drawRect(int x, int y, int width, int height, bool state = true) const;
+  void fillRect(int x, int y, int width, int height, bool state = true) const;
+  void drawImage(const uint8_t bitmap[], int x, int y, int width, int height) const;
+
+  // Text
+  int getTextWidth(int fontId, const char* text, EpdFontStyle style = REGULAR) const;
+  void drawCenteredText(int fontId, int y, const char* text, bool black = true, EpdFontStyle style = REGULAR) const;
+  void drawText(int fontId, int x, int y, const char* text, bool black = true, EpdFontStyle style = REGULAR) const;
+  void setFontRenderMode(const FontRenderMode mode) { this->fontRenderMode = mode; }
+  int getSpaceWidth(int fontId) const;
+  int getLineHeight(int fontId) const;
+
+  // Low level functions
+  uint8_t* getFrameBuffer() const;
+  void swapBuffers() const;
+  void grayscaleRevert() const;
+  void copyGrayscaleLsbBuffers() const;
+  void copyGrayscaleMsbBuffers() const;
+  void displayGrayBuffer() const;
+};

lib/ZipFile/ZipFile.cpp

@@ -7,7 +7,7 @@ bool inflateOneShot(const uint8_t* inputBuf, const size_t deflatedSize, uint8_t*
   // Setup inflator
   const auto inflator = static_cast<tinfl_decompressor*>(malloc(sizeof(tinfl_decompressor)));
   if (!inflator) {
-    Serial.println("Failed to allocate memory for inflator");
+    Serial.printf("[%lu] [ZIP] Failed to allocate memory for inflator\n", millis());
     return false;
   }
   memset(inflator, 0, sizeof(tinfl_decompressor));
@@ -20,7 +20,7 @@ bool inflateOneShot(const uint8_t* inputBuf, const size_t deflatedSize, uint8_t*
   free(inflator);
 
   if (status != TINFL_STATUS_DONE) {
-    Serial.printf("tinfl_decompress() failed with status %d\n", status);
+    Serial.printf("[%lu] [ZIP] tinfl_decompress() failed with status %d\n", millis(), status);
     return false;
   }
 
@@ -32,20 +32,22 @@ bool ZipFile::loadFileStat(const char* filename, mz_zip_archive_file_stat* fileS
   const bool status = mz_zip_reader_init_file(&zipArchive, filePath.c_str(), 0);
 
   if (!status) {
-    Serial.printf("mz_zip_reader_init_file() failed!\nError %s\n", mz_zip_get_error_string(zipArchive.m_last_error));
+    Serial.printf("[%lu] [ZIP] mz_zip_reader_init_file() failed! Error: %s\n", millis(),
+                  mz_zip_get_error_string(zipArchive.m_last_error));
     return false;
   }
 
   // find the file
   mz_uint32 fileIndex = 0;
   if (!mz_zip_reader_locate_file_v2(&zipArchive, filename, nullptr, 0, &fileIndex)) {
-    Serial.printf("Could not find file %s\n", filename);
+    Serial.printf("[%lu] [ZIP] Could not find file %s\n", millis(), filename);
     mz_zip_reader_end(&zipArchive);
     return false;
   }
 
   if (!mz_zip_reader_file_stat(&zipArchive, fileIndex, fileStat)) {
-    Serial.printf("mz_zip_reader_file_stat() failed!\nError %s\n", mz_zip_get_error_string(zipArchive.m_last_error));
+    Serial.printf("[%lu] [ZIP] mz_zip_reader_file_stat() failed! Error: %s\n", millis(),
+                  mz_zip_get_error_string(zipArchive.m_last_error));
     mz_zip_reader_end(&zipArchive);
     return false;
   }
@@ -65,13 +67,13 @@ long ZipFile::getDataOffset(const mz_zip_archive_file_stat& fileStat) const {
   fclose(file);
 
   if (read != localHeaderSize) {
-    Serial.println("Something went wrong reading the local header");
+    Serial.printf("[%lu] [ZIP] Something went wrong reading the local header\n", millis());
     return -1;
   }
 
   if (pLocalHeader[0] + (pLocalHeader[1] << 8) + (pLocalHeader[2] << 16) + (pLocalHeader[3] << 24) !=
       0x04034b50 /* MZ_ZIP_LOCAL_DIR_HEADER_SIG */) {
-    Serial.println("Not a valid zip file header");
+    Serial.printf("[%lu] [ZIP] Not a valid zip file header\n", millis());
     return -1;
   }
 
@@ -80,6 +82,16 @@ long ZipFile::getDataOffset(const mz_zip_archive_file_stat& fileStat) const {
   return fileOffset + localHeaderSize + filenameLength + extraOffset;
 }
 
+bool ZipFile::getInflatedFileSize(const char* filename, size_t* size) const {
+  mz_zip_archive_file_stat fileStat;
+  if (!loadFileStat(filename, &fileStat)) {
+    return false;
+  }
+
+  *size = static_cast<size_t>(fileStat.m_uncomp_size);
+  return true;
+}
+
 uint8_t* ZipFile::readFileToMemory(const char* filename, size_t* size, const bool trailingNullByte) const {
   mz_zip_archive_file_stat fileStat;
   if (!loadFileStat(filename, &fileStat)) {
@@ -105,7 +117,7 @@ uint8_t* ZipFile::readFileToMemory(const char* filename, size_t* size, const boo
     fclose(file);
 
     if (dataRead != inflatedDataSize) {
-      Serial.println("Failed to read data");
+      Serial.printf("[%lu] [ZIP] Failed to read data\n", millis());
       free(data);
       return nullptr;
     }
@@ -115,7 +127,7 @@ uint8_t* ZipFile::readFileToMemory(const char* filename, size_t* size, const boo
     // Read out deflated content from file
     const auto deflatedData = static_cast<uint8_t*>(malloc(deflatedDataSize));
     if (deflatedData == nullptr) {
-      Serial.println("Failed to allocate memory for decompression buffer");
+      Serial.printf("[%lu] [ZIP] Failed to allocate memory for decompression buffer\n", millis());
       fclose(file);
       return nullptr;
     }
@@ -124,7 +136,7 @@ uint8_t* ZipFile::readFileToMemory(const char* filename, size_t* size, const boo
     fclose(file);
 
     if (dataRead != deflatedDataSize) {
-      Serial.printf("Failed to read data, expected %d got %d\n", deflatedDataSize, dataRead);
+      Serial.printf("[%lu] [ZIP] Failed to read data, expected %d got %d\n", millis(), deflatedDataSize, dataRead);
       free(deflatedData);
       free(data);
       return nullptr;
@@ -134,14 +146,14 @@ uint8_t* ZipFile::readFileToMemory(const char* filename, size_t* size, const boo
     free(deflatedData);
 
     if (!success) {
-      Serial.println("Failed to inflate file");
+      Serial.printf("[%lu] [ZIP] Failed to inflate file\n", millis());
       free(data);
       return nullptr;
     }
 
     // Continue out of block with data set
   } else {
-    Serial.println("Unsupported compression method");
+    Serial.printf("[%lu] [ZIP] Unsupported compression method\n", millis());
     fclose(file);
     return nullptr;
   }
@@ -172,7 +184,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     // no deflation, just read content
     const auto buffer = static_cast<uint8_t*>(malloc(chunkSize));
     if (!buffer) {
-      Serial.println("Failed to allocate memory for buffer");
+      Serial.printf("[%lu] [ZIP] Failed to allocate memory for buffer\n", millis());
       fclose(file);
       return false;
     }
@@ -181,7 +193,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     while (remaining > 0) {
       const size_t dataRead = fread(buffer, 1, remaining < chunkSize ? remaining : chunkSize, file);
       if (dataRead == 0) {
-        Serial.println("Could not read more bytes");
+        Serial.printf("[%lu] [ZIP] Could not read more bytes\n", millis());
         free(buffer);
         fclose(file);
         return false;
@@ -200,7 +212,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     // Setup inflator
     const auto inflator = static_cast<tinfl_decompressor*>(malloc(sizeof(tinfl_decompressor)));
     if (!inflator) {
-      Serial.println("Failed to allocate memory for inflator");
+      Serial.printf("[%lu] [ZIP] Failed to allocate memory for inflator\n", millis());
       fclose(file);
       return false;
     }
@@ -210,7 +222,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     // Setup file read buffer
     const auto fileReadBuffer = static_cast<uint8_t*>(malloc(chunkSize));
     if (!fileReadBuffer) {
-      Serial.println("Failed to allocate memory for zip file read buffer");
+      Serial.printf("[%lu] [ZIP] Failed to allocate memory for zip file read buffer\n", millis());
       free(inflator);
       fclose(file);
       return false;
@@ -218,7 +230,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
 
     const auto outputBuffer = static_cast<uint8_t*>(malloc(TINFL_LZ_DICT_SIZE));
     if (!outputBuffer) {
-      Serial.println("Failed to allocate memory for dictionary");
+      Serial.printf("[%lu] [ZIP] Failed to allocate memory for dictionary\n", millis());
       free(inflator);
       free(fileReadBuffer);
       fclose(file);
@@ -266,16 +278,20 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
       // Write output chunk
       if (outBytes > 0) {
         processedOutputBytes += outBytes;
-        out.write(outputBuffer + outputCursor, outBytes);
+        if (out.write(outputBuffer + outputCursor, outBytes) != outBytes) {
+          Serial.printf("[%lu] [ZIP] Failed to write all output bytes to stream\n", millis());
+          fclose(file);
+          free(outputBuffer);
+          free(fileReadBuffer);
+          free(inflator);
+          return false;
+        }
         // Update output position in buffer (with wraparound)
         outputCursor = (outputCursor + outBytes) & (TINFL_LZ_DICT_SIZE - 1);
       }
 
-      Serial.printf("Decompressing - %d/%d deflated into %d/%d inflated\n", deflatedDataSize - fileRemainingBytes,
-                    deflatedDataSize, processedOutputBytes, inflatedDataSize);
-
       if (status < 0) {
-        Serial.printf("tinfl_decompress() failed with status %d\n", status);
+        Serial.printf("[%lu] [ZIP] tinfl_decompress() failed with status %d\n", millis(), status);
         fclose(file);
         free(outputBuffer);
         free(fileReadBuffer);
@@ -284,7 +300,8 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
       }
 
       if (status == TINFL_STATUS_DONE) {
-        Serial.println("Decompression finished");
+        Serial.printf("[%lu] [ZIP] Decompressed %d bytes into %d bytes\n", millis(), deflatedDataSize,
+                      inflatedDataSize);
         fclose(file);
         free(inflator);
         free(fileReadBuffer);
@@ -294,7 +311,7 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     }
 
     // If we get here, EOF reached without TINFL_STATUS_DONE
-    Serial.println("Unexpected EOF");
+    Serial.printf("[%lu] [ZIP] Unexpected EOF\n", millis());
     fclose(file);
     free(outputBuffer);
     free(fileReadBuffer);
@@ -302,6 +319,6 @@ bool ZipFile::readFileToStream(const char* filename, Print& out, const size_t ch
     return false;
   }
 
-  Serial.println("Unsupported compression method");
+  Serial.printf("[%lu] [ZIP] Unsupported compression method\n", millis());
   return false;
 }

lib/ZipFile/ZipFile.h

@@ -14,6 +14,7 @@ class ZipFile {
  public:
   explicit ZipFile(std::string filePath) : filePath(std::move(filePath)) {}
   ~ZipFile() = default;
+  bool getInflatedFileSize(const char* filename, size_t* size) const;
   uint8_t* readFileToMemory(const char* filename, size_t* size = nullptr, bool trailingNullByte = false) const;
   bool readFileToStream(const char* filename, Print& out, size_t chunkSize) const;
 };

platformio.ini

@@ -1,14 +1,8 @@
-; PlatformIO Project Configuration File
+[platformio]
-;
+crosspoint_version = 0.5.1
-;   Build options: build flags, source filter
+default_envs = default
-;   Upload options: custom upload port, speed and extra flags
-;   Library options: dependencies, extra library storages
-;   Advanced options: extra scripting
-;
-; Please visit documentation for the other options and examples
-; https://docs.platformio.org/page/projectconf.html
 
-[env:esp32-c3-devkitm-1]
+[base]
 platform = espressif32
 board = esp32-c3-devkitm-1
 framework = arduino
@@ -19,22 +13,34 @@ board_upload.flash_size = 16MB
 board_upload.maximum_size = 16777216
 board_upload.offset_address = 0x10000
 
+build_flags =
+  -DARDUINO_USB_MODE=1
+  -DARDUINO_USB_CDC_ON_BOOT=1
+  -DMINIZ_NO_ZLIB_COMPATIBLE_NAMES=1
+# https://libexpat.github.io/doc/api/latest/#XML_GE
+  -DXML_GE=0
+  -DXML_CONTEXT_BYTES=1024
+  -std=c++2a
+
 ; Board configuration
 board_build.flash_mode = dio
 board_build.flash_size = 16MB
 board_build.partitions = partitions.csv
 
-build_flags =
-  -DARDUINO_USB_MODE=1
-  -DARDUINO_USB_CDC_ON_BOOT=1
-  -DMINIZ_NO_ZLIB_COMPATIBLE_NAMES=1
-  # https://libexpat.github.io/doc/api/latest/#XML_GE
-  -DXML_GE=0
-  -DXML_CONTEXT_BYTES=1024
-
 ; Libraries
 lib_deps =
-  zinggjm/GxEPD2@^1.6.5
-  https://github.com/leethomason/tinyxml2.git#11.0.0
   BatteryMonitor=symlink://open-x4-sdk/libs/hardware/BatteryMonitor
   InputManager=symlink://open-x4-sdk/libs/hardware/InputManager
+  EInkDisplay=symlink://open-x4-sdk/libs/display/EInkDisplay
+
+[env:default]
+extends = base
+build_flags =
+  ${base.build_flags}
+  -DCROSSPOINT_VERSION=\"${platformio.crosspoint_version}-dev\"
+
+[env:gh_release]
+extends = base
+build_flags =
+  ${base.build_flags}
+  -DCROSSPOINT_VERSION=\"${platformio.crosspoint_version}\"

src/CrossPointState.cpp

@@ -23,7 +23,7 @@ bool CrossPointState::loadFromFile() {
   uint8_t version;
   serialization::readPod(inputFile, version);
   if (version != STATE_FILE_VERSION) {
-    Serial.printf("CrossPointState: Unknown version %u\n", version);
+    Serial.printf("[%lu] [CPS] Deserialization failed: Unknown version %u\n", millis(), version);
     inputFile.close();
     return false;
   }

src/config.h

@@ -0,0 +1,29 @@
+#pragma once
+
+/**
+ * Generated with:
+ *  ruby -rdigest -e 'puts [
+ *    "./lib/EpdFont/builtinFonts/bookerly_2b.h",
+ *    "./lib/EpdFont/builtinFonts/bookerly_bold_2b.h",
+ *    "./lib/EpdFont/builtinFonts/bookerly_bold_italic_2b.h",
+ *    "./lib/EpdFont/builtinFonts/bookerly_italic_2b.h",
+ *  ].map{|f| Digest::SHA256.hexdigest(File.read(f)).to_i(16) }.sum % (2 ** 32) - (2 ** 31)'
+ */
+#define READER_FONT_ID 1747632454
+
+/**
+ * Generated with:
+ *  ruby -rdigest -e 'puts [
+ *    "./lib/EpdFont/builtinFonts/ubuntu_10.h",
+ *    "./lib/EpdFont/builtinFonts/ubuntu_bold_10.h",
+ *  ].map{|f| Digest::SHA256.hexdigest(File.read(f)).to_i(16) }.sum % (2 ** 32) - (2 ** 31)'
+ */
+#define UI_FONT_ID 225955604
+
+/**
+ * Generated with:
+ *  ruby -rdigest -e 'puts [
+ *    "./lib/EpdFont/builtinFonts/pixelarial14.h",
+ *  ].map{|f| Digest::SHA256.hexdigest(File.read(f)).to_i(16) }.sum % (2 ** 32) - (2 ** 31)'
+ */
+#define SMALL_FONT_ID 2037928017

src/images/CrossLarge.h

@@ -1,7 +1,7 @@
 #pragma once
 #include <cstdint>
 
-extern const uint8_t CrossLarge[] = {
+static const uint8_t CrossLarge[] = {
     0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
     0xEF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xF7, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC7, 0xFF, 0xFF,
     0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xE3, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x83, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,

src/main.cpp

@@ -1,13 +1,21 @@
 #include <Arduino.h>
-#include <EpdRenderer.h>
+#include <EInkDisplay.h>
 #include <Epub.h>
-#include <GxEPD2_BW.h>
+#include <GfxRenderer.h>
 #include <InputManager.h>
 #include <SD.h>
 #include <SPI.h>
+#include <builtinFonts/bookerly_2b.h>
+#include <builtinFonts/bookerly_bold_2b.h>
+#include <builtinFonts/bookerly_bold_italic_2b.h>
+#include <builtinFonts/bookerly_italic_2b.h>
+#include <builtinFonts/pixelarial14.h>
+#include <builtinFonts/ubuntu_10.h>
+#include <builtinFonts/ubuntu_bold_10.h>
 
 #include "Battery.h"
 #include "CrossPointState.h"
+#include "config.h"
 #include "screens/BootLogoScreen.h"
 #include "screens/EpubReaderScreen.h"
 #include "screens/FileSelectionScreen.h"
@@ -28,32 +36,44 @@
 #define SD_SPI_CS 12
 #define SD_SPI_MISO 7
 
-GxEPD2_BW<GxEPD2_426_GDEQ0426T82, GxEPD2_426_GDEQ0426T82::HEIGHT> display(GxEPD2_426_GDEQ0426T82(EPD_CS, EPD_DC,
+EInkDisplay einkDisplay(EPD_SCLK, EPD_MOSI, EPD_CS, EPD_DC, EPD_RST, EPD_BUSY);
-                                                                                                 EPD_RST, EPD_BUSY));
 InputManager inputManager;
-EpdRenderer renderer(display);
+GfxRenderer renderer(einkDisplay);
 Screen* currentScreen;
 CrossPointState appState;
 
+// Fonts
+EpdFont bookerlyFont(&bookerly_2b);
+EpdFont bookerlyBoldFont(&bookerly_bold_2b);
+EpdFont bookerlyItalicFont(&bookerly_italic_2b);
+EpdFont bookerlyBoldItalicFont(&bookerly_bold_italic_2b);
+EpdFontFamily bookerlyFontFamily(&bookerlyFont, &bookerlyBoldFont, &bookerlyItalicFont, &bookerlyBoldItalicFont);
+
+EpdFont smallFont(&pixelarial14);
+EpdFontFamily smallFontFamily(&smallFont);
+
+EpdFont ubuntu10Font(&ubuntu_10);
+EpdFont ubuntuBold10Font(&ubuntu_bold_10);
+EpdFontFamily ubuntuFontFamily(&ubuntu10Font, &ubuntuBold10Font);
+
 // Power button timing
 // Time required to confirm boot from sleep
 constexpr unsigned long POWER_BUTTON_WAKEUP_MS = 1000;
 // Time required to enter sleep mode
 constexpr unsigned long POWER_BUTTON_SLEEP_MS = 1000;
 
-Epub* loadEpub(const std::string& path) {
+std::unique_ptr<Epub> loadEpub(const std::string& path) {
   if (!SD.exists(path.c_str())) {
-    Serial.printf("File does not exist: %s\n", path.c_str());
+    Serial.printf("[%lu] [   ] File does not exist: %s\n", millis(), path.c_str());
     return nullptr;
   }
 
-  const auto epub = new Epub(path, "/.crosspoint");
+  auto epub = std::unique_ptr<Epub>(new Epub(path, "/.crosspoint"));
   if (epub->load()) {
     return epub;
   }
 
-  Serial.println("Failed to load epub");
+  Serial.printf("[%lu] [   ] Failed to load epub\n", millis());
-  delete epub;
   return nullptr;
 }
 
@@ -75,15 +95,13 @@ void verifyWakeupLongPress() {
   const auto start = millis();
   bool abort = false;
 
-  Serial.println("Verifying power button press");
+  Serial.printf("[%lu] [   ] Verifying power button press\n", millis());
   inputManager.update();
   while (!inputManager.isPressed(InputManager::BTN_POWER) && millis() - start < 1000) {
     delay(50);
     inputManager.update();
-    Serial.println("Waiting...");
   }
 
-  Serial.printf("Made it? %s\n", inputManager.isPressed(InputManager::BTN_POWER) ? "yes" : "no");
   if (inputManager.isPressed(InputManager::BTN_POWER)) {
     do {
       delay(50);
@@ -94,8 +112,6 @@ void verifyWakeupLongPress() {
     abort = true;
   }
 
-  Serial.printf("held for %lu\n", inputManager.getHeldTime());
-
   if (abort) {
     // Button released too early. Returning to sleep.
     // IMPORTANT: Re-arm the wakeup trigger before sleeping again
@@ -117,13 +133,13 @@ void enterDeepSleep() {
   exitScreen();
   enterNewScreen(new SleepScreen(renderer, inputManager));
 
-  Serial.println("Power button released after a long press. Entering deep sleep.");
+  Serial.printf("[%lu] [   ] Power button released after a long press. Entering deep sleep.\n", millis());
   delay(1000);  // Allow Serial buffer to empty and display to update
 
   // Enable Wakeup on LOW (button press)
   esp_deep_sleep_enable_gpio_wakeup(1ULL << InputManager::POWER_BUTTON_PIN, ESP_GPIO_WAKEUP_GPIO_LOW);
 
-  display.hibernate();
+  einkDisplay.deepSleep();
 
   // Enter Deep Sleep
   esp_deep_sleep_start();
@@ -134,15 +150,16 @@ void onSelectEpubFile(const std::string& path) {
   exitScreen();
   enterNewScreen(new FullScreenMessageScreen(renderer, inputManager, "Loading..."));
 
-  Epub* epub = loadEpub(path);
+  auto epub = loadEpub(path);
   if (epub) {
     appState.openEpubPath = path;
     appState.saveToFile();
     exitScreen();
-    enterNewScreen(new EpubReaderScreen(renderer, inputManager, epub, onGoHome));
+    enterNewScreen(new EpubReaderScreen(renderer, inputManager, std::move(epub), onGoHome));
   } else {
     exitScreen();
-    enterNewScreen(new FullScreenMessageScreen(renderer, inputManager, "Failed to load epub", REGULAR, false, false));
+    enterNewScreen(
+        new FullScreenMessageScreen(renderer, inputManager, "Failed to load epub", REGULAR, EInkDisplay::HALF_REFRESH));
     delay(2000);
     onGoHome();
   }
@@ -154,15 +171,13 @@ void onGoHome() {
 }
 
 void setup() {
+  Serial.begin(115200);
+
+  Serial.printf("[%lu] [   ] Starting CrossPoint version " CROSSPOINT_VERSION "\n", millis());
+
   inputManager.begin();
   verifyWakeupLongPress();
 
-  // Begin serial only if USB connected
-  pinMode(UART0_RXD, INPUT);
-  if (digitalRead(UART0_RXD) == HIGH) {
-    Serial.begin(115200);
-  }
-
   // Initialize pins
   pinMode(BAT_GPIO0, INPUT);
 
@@ -170,11 +185,13 @@ void setup() {
   SPI.begin(EPD_SCLK, SD_SPI_MISO, EPD_MOSI, EPD_CS);
 
   // Initialize display
-  const SPISettings spi_settings(SPI_FQ, MSBFIRST, SPI_MODE0);
+  einkDisplay.begin();
-  display.init(115200, true, 2, false, SPI, spi_settings);
+  Serial.printf("[%lu] [   ] Display initialized\n", millis());
-  display.setRotation(3);  // 270 degrees
+
-  display.setTextColor(GxEPD_BLACK);
+  renderer.insertFont(READER_FONT_ID, bookerlyFontFamily);
-  Serial.println("Display initialized");
+  renderer.insertFont(UI_FONT_ID, ubuntuFontFamily);
+  renderer.insertFont(SMALL_FONT_ID, smallFontFamily);
+  Serial.printf("[%lu] [   ] Fonts setup\n", millis());
 
   exitScreen();
   enterNewScreen(new BootLogoScreen(renderer, inputManager));
@@ -184,10 +201,10 @@ void setup() {
 
   appState.loadFromFile();
   if (!appState.openEpubPath.empty()) {
-    Epub* epub = loadEpub(appState.openEpubPath);
+    auto epub = loadEpub(appState.openEpubPath);
     if (epub) {
       exitScreen();
-      enterNewScreen(new EpubReaderScreen(renderer, inputManager, epub, onGoHome));
+      enterNewScreen(new EpubReaderScreen(renderer, inputManager, std::move(epub), onGoHome));
       // Ensure we're not still holding the power button before leaving setup
       waitForPowerRelease();
       return;
@@ -205,8 +222,8 @@ void loop() {
   delay(10);
 
   static unsigned long lastMemPrint = 0;
-  if (Serial && millis() - lastMemPrint >= 5000) {
+  if (Serial && millis() - lastMemPrint >= 10000) {
-    Serial.printf("[%lu] Memory - Free: %d bytes, Total: %d bytes, Min Free: %d bytes\n", millis(), ESP.getFreeHeap(),
+    Serial.printf("[%lu] [MEM] Free: %d bytes, Total: %d bytes, Min Free: %d bytes\n", millis(), ESP.getFreeHeap(),
                   ESP.getHeapSize(), ESP.getMinFreeHeap());
     lastMemPrint = millis();
   }

src/screens/BootLogoScreen.cpp

@@ -1,14 +1,18 @@
 #include "BootLogoScreen.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
 
+#include "config.h"
 #include "images/CrossLarge.h"
 
 void BootLogoScreen::onEnter() {
-  const auto pageWidth = renderer.getPageWidth();
+  const auto pageWidth = GfxRenderer::getScreenWidth();
-  const auto pageHeight = renderer.getPageHeight();
+  const auto pageHeight = GfxRenderer::getScreenHeight();
 
   renderer.clearScreen();
-  // Location for images is from top right in landscape orientation
+  renderer.drawImage(CrossLarge, (pageWidth - 128) / 2, (pageHeight - 128) / 2, 128, 128);
-  renderer.drawImage(CrossLarge, (pageHeight - 128) / 2, (pageWidth - 128) / 2, 128, 128);
+  renderer.drawCenteredText(UI_FONT_ID, pageHeight / 2 + 70, "CrossPoint", true, BOLD);
+  renderer.drawCenteredText(SMALL_FONT_ID, pageHeight / 2 + 95, "BOOTING");
+  renderer.drawCenteredText(SMALL_FONT_ID, pageHeight - 30, CROSSPOINT_VERSION);
+  renderer.displayBuffer();
 }

src/screens/BootLogoScreen.h

@@ -3,6 +3,6 @@
 
 class BootLogoScreen final : public Screen {
  public:
-  explicit BootLogoScreen(EpdRenderer& renderer, InputManager& inputManager) : Screen(renderer, inputManager) {}
+  explicit BootLogoScreen(GfxRenderer& renderer, InputManager& inputManager) : Screen(renderer, inputManager) {}
   void onEnter() override;
 };

src/screens/EpubReaderChapterSelectionScreen.cpp

@@ -0,0 +1,107 @@
+#include "EpubReaderChapterSelectionScreen.h"
+
+#include <GfxRenderer.h>
+#include <SD.h>
+
+#include "config.h"
+
+constexpr int PAGE_ITEMS = 24;
+constexpr int SKIP_PAGE_MS = 700;
+
+void EpubReaderChapterSelectionScreen::taskTrampoline(void* param) {
+  auto* self = static_cast<EpubReaderChapterSelectionScreen*>(param);
+  self->displayTaskLoop();
+}
+
+void EpubReaderChapterSelectionScreen::onEnter() {
+  if (!epub) {
+    return;
+  }
+
+  renderingMutex = xSemaphoreCreateMutex();
+  selectorIndex = currentSpineIndex;
+
+  // Trigger first update
+  updateRequired = true;
+  xTaskCreate(&EpubReaderChapterSelectionScreen::taskTrampoline, "EpubReaderChapterSelectionScreenTask",
+              2048,               // Stack size
+              this,               // Parameters
+              1,                  // Priority
+              &displayTaskHandle  // Task handle
+  );
+}
+
+void EpubReaderChapterSelectionScreen::onExit() {
+  // Wait until not rendering to delete task to avoid killing mid-instruction to EPD
+  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  if (displayTaskHandle) {
+    vTaskDelete(displayTaskHandle);
+    displayTaskHandle = nullptr;
+  }
+  vSemaphoreDelete(renderingMutex);
+  renderingMutex = nullptr;
+}
+
+void EpubReaderChapterSelectionScreen::handleInput() {
+  const bool prevReleased =
+      inputManager.wasReleased(InputManager::BTN_UP) || inputManager.wasReleased(InputManager::BTN_LEFT);
+  const bool nextReleased =
+      inputManager.wasReleased(InputManager::BTN_DOWN) || inputManager.wasReleased(InputManager::BTN_RIGHT);
+
+  const bool skipPage = inputManager.getHeldTime() > SKIP_PAGE_MS;
+
+  if (inputManager.wasPressed(InputManager::BTN_CONFIRM)) {
+    onSelectSpineIndex(selectorIndex);
+  } else if (inputManager.wasPressed(InputManager::BTN_BACK)) {
+    onGoBack();
+  } else if (prevReleased) {
+    if (skipPage) {
+      selectorIndex =
+          ((selectorIndex / PAGE_ITEMS - 1) * PAGE_ITEMS + epub->getSpineItemsCount()) % epub->getSpineItemsCount();
+    } else {
+      selectorIndex = (selectorIndex + epub->getSpineItemsCount() - 1) % epub->getSpineItemsCount();
+    }
+    updateRequired = true;
+  } else if (nextReleased) {
+    if (skipPage) {
+      selectorIndex = ((selectorIndex / PAGE_ITEMS + 1) * PAGE_ITEMS) % epub->getSpineItemsCount();
+    } else {
+      selectorIndex = (selectorIndex + 1) % epub->getSpineItemsCount();
+    }
+    updateRequired = true;
+  }
+}
+
+void EpubReaderChapterSelectionScreen::displayTaskLoop() {
+  while (true) {
+    if (updateRequired) {
+      updateRequired = false;
+      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      renderScreen();
+      xSemaphoreGive(renderingMutex);
+    }
+    vTaskDelay(10 / portTICK_PERIOD_MS);
+  }
+}
+
+void EpubReaderChapterSelectionScreen::renderScreen() {
+  renderer.clearScreen();
+
+  const auto pageWidth = renderer.getScreenWidth();
+  renderer.drawCenteredText(READER_FONT_ID, 10, "Select Chapter", true, BOLD);
+
+  const auto pageStartIndex = selectorIndex / PAGE_ITEMS * PAGE_ITEMS;
+  renderer.fillRect(0, 60 + (selectorIndex % PAGE_ITEMS) * 30 + 2, pageWidth - 1, 30);
+  for (int i = pageStartIndex; i < epub->getSpineItemsCount() && i < pageStartIndex + PAGE_ITEMS; i++) {
+    const int tocIndex = epub->getTocIndexForSpineIndex(i);
+    if (tocIndex == -1) {
+      renderer.drawText(UI_FONT_ID, 20, 60 + (i % PAGE_ITEMS) * 30, "Unnamed", i != selectorIndex);
+    } else {
+      auto item = epub->getTocItem(tocIndex);
+      renderer.drawText(UI_FONT_ID, 20 + (item.level - 1) * 15, 60 + (i % PAGE_ITEMS) * 30, item.title.c_str(),
+                        i != selectorIndex);
+    }
+  }
+
+  renderer.displayBuffer();
+}

src/screens/EpubReaderChapterSelectionScreen.h

@@ -0,0 +1,38 @@
+#pragma once
+#include <Epub.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/semphr.h>
+#include <freertos/task.h>
+
+#include <memory>
+
+#include "Screen.h"
+
+class EpubReaderChapterSelectionScreen final : public Screen {
+  std::shared_ptr<Epub> epub;
+  TaskHandle_t displayTaskHandle = nullptr;
+  SemaphoreHandle_t renderingMutex = nullptr;
+  int currentSpineIndex = 0;
+  int selectorIndex = 0;
+  bool updateRequired = false;
+  const std::function<void()> onGoBack;
+  const std::function<void(int newSpineIndex)> onSelectSpineIndex;
+
+  static void taskTrampoline(void* param);
+  [[noreturn]] void displayTaskLoop();
+  void renderScreen();
+
+ public:
+  explicit EpubReaderChapterSelectionScreen(GfxRenderer& renderer, InputManager& inputManager,
+                                            const std::shared_ptr<Epub>& epub, const int currentSpineIndex,
+                                            const std::function<void()>& onGoBack,
+                                            const std::function<void(int newSpineIndex)>& onSelectSpineIndex)
+      : Screen(renderer, inputManager),
+        epub(epub),
+        currentSpineIndex(currentSpineIndex),
+        onGoBack(onGoBack),
+        onSelectSpineIndex(onSelectSpineIndex) {}
+  void onEnter() override;
+  void onExit() override;
+  void handleInput() override;
+};

src/screens/EpubReaderScreen.cpp

@@ -1,12 +1,20 @@
 #include "EpubReaderScreen.h"
 
-#include <EpdRenderer.h>
+#include <Epub/Page.h>
+#include <GfxRenderer.h>
 #include <SD.h>
 
 #include "Battery.h"
+#include "EpubReaderChapterSelectionScreen.h"
+#include "config.h"
 
-constexpr int PAGES_PER_REFRESH = 20;
+constexpr int PAGES_PER_REFRESH = 15;
 constexpr unsigned long SKIP_CHAPTER_MS = 700;
+constexpr float lineCompression = 0.95f;
+constexpr int marginTop = 8;
+constexpr int marginRight = 10;
+constexpr int marginBottom = 22;
+constexpr int marginLeft = 10;
 
 void EpubReaderScreen::taskTrampoline(void* param) {
   auto* self = static_cast<EpubReaderScreen*>(param);
@@ -29,7 +37,7 @@ void EpubReaderScreen::onEnter() {
     f.read(data, 4);
     currentSpineIndex = data[0] + (data[1] << 8);
     nextPageNumber = data[2] + (data[3] << 8);
-    Serial.printf("Loaded cache: %d, %d\n", currentSpineIndex, nextPageNumber);
+    Serial.printf("[%lu] [ERS] Loaded cache: %d, %d\n", millis(), currentSpineIndex, nextPageNumber);
     f.close();
   }
 
@@ -53,13 +61,42 @@ void EpubReaderScreen::onExit() {
   }
   vSemaphoreDelete(renderingMutex);
   renderingMutex = nullptr;
-  delete section;
+  section.reset();
-  section = nullptr;
+  epub.reset();
-  delete epub;
-  epub = nullptr;
 }
 
 void EpubReaderScreen::handleInput() {
+  // Pass input responsibility to sub screen if exists
+  if (subScreen) {
+    subScreen->handleInput();
+    return;
+  }
+
+  // Enter chapter selection screen
+  if (inputManager.wasPressed(InputManager::BTN_CONFIRM)) {
+    // Don't start screen transition while rendering
+    xSemaphoreTake(renderingMutex, portMAX_DELAY);
+    subScreen.reset(new EpubReaderChapterSelectionScreen(
+        this->renderer, this->inputManager, epub, currentSpineIndex,
+        [this] {
+          subScreen->onExit();
+          subScreen.reset();
+          updateRequired = true;
+        },
+        [this](const int newSpineIndex) {
+          if (currentSpineIndex != newSpineIndex) {
+            currentSpineIndex = newSpineIndex;
+            nextPageNumber = 0;
+            section.reset();
+          }
+          subScreen->onExit();
+          subScreen.reset();
+          updateRequired = true;
+        }));
+    subScreen->onEnter();
+    xSemaphoreGive(renderingMutex);
+  }
+
   if (inputManager.wasPressed(InputManager::BTN_BACK)) {
     onGoHome();
     return;
@@ -74,6 +111,14 @@ void EpubReaderScreen::handleInput() {
     return;
   }
 
+  // any botton press when at end of the book goes back to the last page
+  if (currentSpineIndex > 0 && currentSpineIndex >= epub->getSpineItemsCount()) {
+    currentSpineIndex = epub->getSpineItemsCount() - 1;
+    nextPageNumber = UINT16_MAX;
+    updateRequired = true;
+    return;
+  }
+
   const bool skipChapter = inputManager.getHeldTime() > SKIP_CHAPTER_MS;
 
   if (skipChapter) {
@@ -81,8 +126,7 @@ void EpubReaderScreen::handleInput() {
     xSemaphoreTake(renderingMutex, portMAX_DELAY);
     nextPageNumber = 0;
     currentSpineIndex = nextReleased ? currentSpineIndex + 1 : currentSpineIndex - 1;
-    delete section;
+    section.reset();
-    section = nullptr;
     xSemaphoreGive(renderingMutex);
     updateRequired = true;
     return;
@@ -102,8 +146,7 @@ void EpubReaderScreen::handleInput() {
       xSemaphoreTake(renderingMutex, portMAX_DELAY);
       nextPageNumber = UINT16_MAX;
       currentSpineIndex--;
-      delete section;
+      section.reset();
-      section = nullptr;
       xSemaphoreGive(renderingMutex);
     }
     updateRequired = true;
@@ -115,8 +158,7 @@ void EpubReaderScreen::handleInput() {
       xSemaphoreTake(renderingMutex, portMAX_DELAY);
       nextPageNumber = 0;
       currentSpineIndex++;
-      delete section;
+      section.reset();
-      section = nullptr;
       xSemaphoreGive(renderingMutex);
     }
     updateRequired = true;
@@ -128,7 +170,7 @@ void EpubReaderScreen::displayTaskLoop() {
     if (updateRequired) {
       updateRequired = false;
       xSemaphoreTake(renderingMutex, portMAX_DELAY);
-      renderPage();
+      renderScreen();
       xSemaphoreGive(renderingMutex);
     }
     vTaskDelay(10 / portTICK_PERIOD_MS);
@@ -136,44 +178,63 @@ void EpubReaderScreen::displayTaskLoop() {
 }
 
 // TODO: Failure handling
-void EpubReaderScreen::renderPage() {
+void EpubReaderScreen::renderScreen() {
   if (!epub) {
     return;
   }
 
-  if (currentSpineIndex >= epub->getSpineItemsCount() || currentSpineIndex < 0) {
+  // edge case handling for sub-zero spine index
+  if (currentSpineIndex < 0) {
     currentSpineIndex = 0;
   }
+  // based bounds of book, show end of book screen
+  if (currentSpineIndex > epub->getSpineItemsCount()) {
+    currentSpineIndex = epub->getSpineItemsCount();
+  }
+
+  // Show end of book screen
+  if (currentSpineIndex == epub->getSpineItemsCount()) {
+    renderer.clearScreen();
+    renderer.drawCenteredText(READER_FONT_ID, 300, "End of book", true, BOLD);
+    renderer.displayBuffer();
+    return;
+  }
 
   if (!section) {
     const auto filepath = epub->getSpineItem(currentSpineIndex);
-    Serial.printf("Loading file: %s, index: %d\n", filepath.c_str(), currentSpineIndex);
+    Serial.printf("[%lu] [ERS] Loading file: %s, index: %d\n", millis(), filepath.c_str(), currentSpineIndex);
-    section = new Section(epub, currentSpineIndex, renderer);
+    section = std::unique_ptr<Section>(new Section(epub, currentSpineIndex, renderer));
-    if (!section->loadCacheMetadata()) {
+    if (!section->loadCacheMetadata(READER_FONT_ID, lineCompression, marginTop, marginRight, marginBottom,
-      Serial.println("Cache not found, building...");
+                                    marginLeft)) {
+      Serial.printf("[%lu] [ERS] Cache not found, building...\n", millis());
 
       {
-        const int textWidth = renderer.getTextWidth("Indexing...");
+        const int textWidth = renderer.getTextWidth(READER_FONT_ID, "Indexing...");
         constexpr int margin = 20;
-        const int x = (renderer.getPageWidth() - textWidth - margin * 2) / 2;
+        const int x = (GfxRenderer::getScreenWidth() - textWidth - margin * 2) / 2;
         constexpr int y = 50;
         const int w = textWidth + margin * 2;
-        const int h = renderer.getLineHeight() + margin * 2;
+        const int h = renderer.getLineHeight(READER_FONT_ID) + margin * 2;
+        renderer.grayscaleRevert();
+        uint8_t* fb1 = renderer.getFrameBuffer();
+        renderer.swapBuffers();
+        memcpy(fb1, renderer.getFrameBuffer(), EInkDisplay::BUFFER_SIZE);
         renderer.fillRect(x, y, w, h, 0);
-        renderer.drawText(x + margin, y + margin, "Indexing...");
+        renderer.drawText(READER_FONT_ID, x + margin, y + margin, "Indexing...");
         renderer.drawRect(x + 5, y + 5, w - 10, h - 10);
-        renderer.flushArea(x, y, w, h);
+        renderer.displayBuffer();
+        pagesUntilFullRefresh = 0;
       }
 
       section->setupCacheDir();
-      if (!section->persistPageDataToSD()) {
+      if (!section->persistPageDataToSD(READER_FONT_ID, lineCompression, marginTop, marginRight, marginBottom,
-        Serial.println("Failed to persist page data to SD");
+                                        marginLeft)) {
-        delete section;
+        Serial.printf("[%lu] [ERS] Failed to persist page data to SD\n", millis());
-        section = nullptr;
+        section.reset();
         return;
       }
     } else {
-      Serial.println("Cache found, skipping build...");
+      Serial.printf("[%lu] [ERS] Cache found, skipping build...\n", millis());
     }
 
     if (nextPageNumber == UINT16_MAX) {
@@ -184,14 +245,34 @@ void EpubReaderScreen::renderPage() {
   }
 
   renderer.clearScreen();
-  section->renderPage();
+
-  renderStatusBar();
+  if (section->pageCount == 0) {
-  if (pagesUntilFullRefresh <= 1) {
+    Serial.printf("[%lu] [ERS] No pages to render\n", millis());
-    renderer.flushDisplay(false);
+    renderer.drawCenteredText(READER_FONT_ID, 300, "Empty chapter", true, BOLD);
-    pagesUntilFullRefresh = PAGES_PER_REFRESH;
+    renderStatusBar();
-  } else {
+    renderer.displayBuffer();
-    renderer.flushDisplay();
+    return;
-    pagesUntilFullRefresh--;
+  }
+
+  if (section->currentPage < 0 || section->currentPage >= section->pageCount) {
+    Serial.printf("[%lu] [ERS] Page out of bounds: %d (max %d)\n", millis(), section->currentPage, section->pageCount);
+    renderer.drawCenteredText(READER_FONT_ID, 300, "Out of bounds", true, BOLD);
+    renderStatusBar();
+    renderer.displayBuffer();
+    return;
+  }
+
+  {
+    auto p = section->loadPageFromSD();
+    if (!p) {
+      Serial.printf("[%lu] [ERS] Failed to load page from SD - clearing section cache\n", millis());
+      section->clearCache();
+      section.reset();
+      return renderScreen();
+    }
+    const auto start = millis();
+    renderContents(std::move(p));
+    Serial.printf("[%lu] [ERS] Rendered page in %dms\n", millis(), millis() - start);
   }
 
   File f = SD.open((epub->getCachePath() + "/progress.bin").c_str(), FILE_WRITE);
@@ -204,23 +285,56 @@ void EpubReaderScreen::renderPage() {
   f.close();
 }
 
+void EpubReaderScreen::renderContents(std::unique_ptr<Page> page) {
+  page->render(renderer, READER_FONT_ID);
+  renderStatusBar();
+  if (pagesUntilFullRefresh <= 1) {
+    renderer.displayBuffer(EInkDisplay::HALF_REFRESH);
+    pagesUntilFullRefresh = PAGES_PER_REFRESH;
+  } else {
+    renderer.displayBuffer();
+    pagesUntilFullRefresh--;
+  }
+
+  // grayscale rendering
+  // TODO: Only do this if font supports it
+  {
+    renderer.clearScreen(0x00);
+    renderer.setFontRenderMode(GfxRenderer::GRAYSCALE_LSB);
+    page->render(renderer, READER_FONT_ID);
+    renderer.copyGrayscaleLsbBuffers();
+
+    // Render and copy to MSB buffer
+    renderer.clearScreen(0x00);
+    renderer.setFontRenderMode(GfxRenderer::GRAYSCALE_MSB);
+    page->render(renderer, READER_FONT_ID);
+    renderer.copyGrayscaleMsbBuffers();
+
+    // display grayscale part
+    renderer.displayGrayBuffer();
+    renderer.setFontRenderMode(GfxRenderer::BW);
+  }
+}
+
 void EpubReaderScreen::renderStatusBar() const {
-  const auto pageWidth = renderer.getPageWidth();
+  constexpr auto textY = 776;
-
+  // Right aligned text for progress counter
   const std::string progress = std::to_string(section->currentPage + 1) + " / " + std::to_string(section->pageCount);
-  const auto progressTextWidth = renderer.getSmallTextWidth(progress.c_str());
+  const auto progressTextWidth = renderer.getTextWidth(SMALL_FONT_ID, progress.c_str());
-  renderer.drawSmallText(pageWidth - progressTextWidth, 765, progress.c_str());
+  renderer.drawText(SMALL_FONT_ID, GfxRenderer::getScreenWidth() - marginRight - progressTextWidth, textY,
+                    progress.c_str());
 
+  // Left aligned battery icon and percentage
   const uint16_t percentage = battery.readPercentage();
   const auto percentageText = std::to_string(percentage) + "%";
-  const auto percentageTextWidth = renderer.getSmallTextWidth(percentageText.c_str());
+  const auto percentageTextWidth = renderer.getTextWidth(SMALL_FONT_ID, percentageText.c_str());
-  renderer.drawSmallText(20, 765, percentageText.c_str());
+  renderer.drawText(SMALL_FONT_ID, 20 + marginLeft, textY, percentageText.c_str());
 
   // 1 column on left, 2 columns on right, 5 columns of battery body
   constexpr int batteryWidth = 15;
   constexpr int batteryHeight = 10;
-  constexpr int x = 0;
+  constexpr int x = marginLeft;
-  constexpr int y = 772;
+  constexpr int y = 783;
 
   // Top line
   renderer.drawLine(x, y, x + batteryWidth - 4, y);
@@ -230,8 +344,8 @@ void EpubReaderScreen::renderStatusBar() const {
   renderer.drawLine(x, y, x, y + batteryHeight - 1);
   // Battery end
   renderer.drawLine(x + batteryWidth - 4, y, x + batteryWidth - 4, y + batteryHeight - 1);
-  renderer.drawLine(x + batteryWidth - 3, y + 2, x + batteryWidth - 3, y + batteryHeight - 3);
+  renderer.drawLine(x + batteryWidth - 3, y + 2, x + batteryWidth - 1, y + 2);
-  renderer.drawLine(x + batteryWidth - 2, y + 2, x + batteryWidth - 2, y + batteryHeight - 3);
+  renderer.drawLine(x + batteryWidth - 3, y + batteryHeight - 3, x + batteryWidth - 1, y + batteryHeight - 3);
   renderer.drawLine(x + batteryWidth - 1, y + 2, x + batteryWidth - 1, y + batteryHeight - 3);
 
   // The +1 is to round up, so that we always fill at least one pixel
@@ -241,17 +355,27 @@ void EpubReaderScreen::renderStatusBar() const {
   }
   renderer.fillRect(x + 1, y + 1, filledWidth, batteryHeight - 2);
 
+  // Centered chatper title text
   // Page width minus existing content with 30px padding on each side
-  const int leftMargin = 20 + percentageTextWidth + 30;
+  const int titleMarginLeft = 20 + percentageTextWidth + 30 + marginLeft;
-  const int rightMargin = progressTextWidth + 30;
+  const int titleMarginRight = progressTextWidth + 30 + marginRight;
-  const int availableTextWidth = pageWidth - leftMargin - rightMargin;
+  const int availableTextWidth = GfxRenderer::getScreenWidth() - titleMarginLeft - titleMarginRight;
-  const auto tocItem = epub->getTocItem(epub->getTocIndexForSpineIndex(currentSpineIndex));
+  const int tocIndex = epub->getTocIndexForSpineIndex(currentSpineIndex);
-  auto title = tocItem.title;
+
-  int titleWidth = renderer.getSmallTextWidth(title.c_str());
+  std::string title;
-  while (titleWidth > availableTextWidth) {
+  int titleWidth;
-    title = title.substr(0, title.length() - 8) + "...";
+  if (tocIndex == -1) {
-    titleWidth = renderer.getSmallTextWidth(title.c_str());
+    title = "Unnamed";
+    titleWidth = renderer.getTextWidth(SMALL_FONT_ID, "Unnamed");
+  } else {
+    const auto tocItem = epub->getTocItem(tocIndex);
+    title = tocItem.title;
+    titleWidth = renderer.getTextWidth(SMALL_FONT_ID, title.c_str());
+    while (titleWidth > availableTextWidth) {
+      title = title.substr(0, title.length() - 8) + "...";
+      titleWidth = renderer.getTextWidth(SMALL_FONT_ID, title.c_str());
+    }
   }
 
-  renderer.drawSmallText(leftMargin + (availableTextWidth - titleWidth) / 2, 765, title.c_str());
+  renderer.drawText(SMALL_FONT_ID, titleMarginLeft + (availableTextWidth - titleWidth) / 2, textY, title.c_str());
 }

src/screens/EpubReaderScreen.h

@@ -8,10 +8,11 @@
 #include "Screen.h"
 
 class EpubReaderScreen final : public Screen {
-  Epub* epub;
+  std::shared_ptr<Epub> epub;
-  Section* section = nullptr;
+  std::unique_ptr<Section> section = nullptr;
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  std::unique_ptr<Screen> subScreen = nullptr;
   int currentSpineIndex = 0;
   int nextPageNumber = 0;
   int pagesUntilFullRefresh = 0;
@@ -20,13 +21,14 @@ class EpubReaderScreen final : public Screen {
 
   static void taskTrampoline(void* param);
   [[noreturn]] void displayTaskLoop();
-  void renderPage();
+  void renderScreen();
+  void renderContents(std::unique_ptr<Page> p);
   void renderStatusBar() const;
 
  public:
-  explicit EpubReaderScreen(EpdRenderer& renderer, InputManager& inputManager, Epub* epub,
+  explicit EpubReaderScreen(GfxRenderer& renderer, InputManager& inputManager, std::unique_ptr<Epub> epub,
                             const std::function<void()>& onGoHome)
-      : Screen(renderer, inputManager), epub(epub), onGoHome(onGoHome) {}
+      : Screen(renderer, inputManager), epub(std::move(epub)), onGoHome(onGoHome) {}
   void onEnter() override;
   void onExit() override;
   void handleInput() override;

src/screens/FileSelectionScreen.cpp

@@ -1,8 +1,10 @@
 #include "FileSelectionScreen.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
 #include <SD.h>
 
+#include "config.h"
+
 void sortFileList(std::vector<std::string>& strs) {
   std::sort(begin(strs), end(strs), [](const std::string& str1, const std::string& str2) {
     if (str1.back() == '/' && str2.back() != '/') return true;
@@ -51,7 +53,7 @@ void FileSelectionScreen::onEnter() {
   updateRequired = true;
 
   xTaskCreate(&FileSelectionScreen::taskTrampoline, "FileSelectionScreenTask",
-              1024,               // Stack size
+              2048,               // Stack size
               this,               // Parameters
               1,                  // Priority
               &displayTaskHandle  // Task handle
@@ -118,21 +120,20 @@ void FileSelectionScreen::displayTaskLoop() {
 void FileSelectionScreen::render() const {
   renderer.clearScreen();
 
-  const auto pageWidth = renderer.getPageWidth();
+  const auto pageWidth = GfxRenderer::getScreenWidth();
-  const auto titleWidth = renderer.getTextWidth("CrossPoint Reader", BOLD);
+  renderer.drawCenteredText(READER_FONT_ID, 10, "CrossPoint Reader", true, BOLD);
-  renderer.drawText((pageWidth - titleWidth) / 2, 0, "CrossPoint Reader", 1, BOLD);
 
   if (files.empty()) {
-    renderer.drawUiText(10, 50, "No EPUBs found");
+    renderer.drawText(UI_FONT_ID, 20, 60, "No EPUBs found");
   } else {
     // Draw selection
-    renderer.fillRect(0, 50 + selectorIndex * 30 + 2, pageWidth - 1, 30);
+    renderer.fillRect(0, 60 + selectorIndex * 30 + 2, pageWidth - 1, 30);
 
     for (size_t i = 0; i < files.size(); i++) {
       const auto file = files[i];
-      renderer.drawUiText(10, 50 + i * 30, file.c_str(), i == selectorIndex ? 0 : 1);
+      renderer.drawText(UI_FONT_ID, 20, 60 + i * 30, file.c_str(), i != selectorIndex);
     }
   }
 
-  renderer.flushDisplay();
+  renderer.displayBuffer();
 }

src/screens/FileSelectionScreen.h

@@ -24,7 +24,7 @@ class FileSelectionScreen final : public Screen {
   void loadFiles();
 
  public:
-  explicit FileSelectionScreen(EpdRenderer& renderer, InputManager& inputManager,
+  explicit FileSelectionScreen(GfxRenderer& renderer, InputManager& inputManager,
                                const std::function<void(const std::string&)>& onSelect)
       : Screen(renderer, inputManager), onSelect(onSelect) {}
   void onEnter() override;

src/screens/FullScreenMessageScreen.cpp

@@ -1,14 +1,14 @@
 #include "FullScreenMessageScreen.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
+
+#include "config.h"
 
 void FullScreenMessageScreen::onEnter() {
-  const auto width = renderer.getUiTextWidth(text.c_str(), style);
+  const auto height = renderer.getLineHeight(UI_FONT_ID);
-  const auto height = renderer.getLineHeight();
+  const auto top = (GfxRenderer::getScreenHeight() - height) / 2;
-  const auto left = (renderer.getPageWidth() - width) / 2;
-  const auto top = (renderer.getPageHeight() - height) / 2;
 
-  renderer.clearScreen(invert);
+  renderer.clearScreen();
-  renderer.drawUiText(left, top, text.c_str(), invert ? 0 : 1, style);
+  renderer.drawCenteredText(UI_FONT_ID, top, text.c_str(), true, style);
-  renderer.flushDisplay(partialUpdate);
+  renderer.displayBuffer(refreshMode);
 }

src/screens/FullScreenMessageScreen.h

@@ -1,24 +1,21 @@
 #pragma once
+#include <EInkDisplay.h>
+#include <EpdFontFamily.h>
+
 #include <string>
 #include <utility>
 
-#include "EpdFontFamily.h"
 #include "Screen.h"
 
 class FullScreenMessageScreen final : public Screen {
   std::string text;
   EpdFontStyle style;
-  bool invert;
+  EInkDisplay::RefreshMode refreshMode;
-  bool partialUpdate;
 
  public:
-  explicit FullScreenMessageScreen(EpdRenderer& renderer, InputManager& inputManager, std::string text,
+  explicit FullScreenMessageScreen(GfxRenderer& renderer, InputManager& inputManager, std::string text,
-                                   const EpdFontStyle style = REGULAR, const bool invert = false,
+                                   const EpdFontStyle style = REGULAR,
-                                   const bool partialUpdate = true)
+                                   const EInkDisplay::RefreshMode refreshMode = EInkDisplay::FAST_REFRESH)
-      : Screen(renderer, inputManager),
+      : Screen(renderer, inputManager), text(std::move(text)), style(style), refreshMode(refreshMode) {}
-        text(std::move(text)),
-        style(style),
-        invert(invert),
-        partialUpdate(partialUpdate) {}
   void onEnter() override;
 };

src/screens/Screen.h

@@ -1,15 +1,15 @@
 #pragma once
 #include <InputManager.h>
 
-class EpdRenderer;
+class GfxRenderer;
 
 class Screen {
  protected:
-  EpdRenderer& renderer;
+  GfxRenderer& renderer;
   InputManager& inputManager;
 
  public:
-  explicit Screen(EpdRenderer& renderer, InputManager& inputManager) : renderer(renderer), inputManager(inputManager) {}
+  explicit Screen(GfxRenderer& renderer, InputManager& inputManager) : renderer(renderer), inputManager(inputManager) {}
   virtual ~Screen() = default;
   virtual void onEnter() {}
   virtual void onExit() {}

src/screens/SleepScreen.cpp

@@ -1,7 +1,18 @@
 #include "SleepScreen.h"
 
-#include <EpdRenderer.h>
+#include <GfxRenderer.h>
 
-#include "images/SleepScreenImg.h"
+#include "config.h"
+#include "images/CrossLarge.h"
 
-void SleepScreen::onEnter() { renderer.drawImageNoMargin(SleepScreenImg, 0, 0, 800, 480, false, true); }
+void SleepScreen::onEnter() {
+  const auto pageWidth = GfxRenderer::getScreenWidth();
+  const auto pageHeight = GfxRenderer::getScreenHeight();
+
+  renderer.clearScreen();
+  renderer.drawImage(CrossLarge, (pageWidth - 128) / 2, (pageHeight - 128) / 2, 128, 128);
+  renderer.drawCenteredText(UI_FONT_ID, pageHeight / 2 + 70, "CrossPoint", true, BOLD);
+  renderer.drawCenteredText(SMALL_FONT_ID, pageHeight / 2 + 95, "SLEEPING");
+  renderer.invertScreen();
+  renderer.displayBuffer(EInkDisplay::HALF_REFRESH);
+}

src/screens/SleepScreen.h

@@ -3,6 +3,6 @@
 
 class SleepScreen final : public Screen {
  public:
-  explicit SleepScreen(EpdRenderer& renderer, InputManager& inputManager) : Screen(renderer, inputManager) {}
+  explicit SleepScreen(GfxRenderer& renderer, InputManager& inputManager) : Screen(renderer, inputManager) {}
   void onEnter() override;
 };