## Summary
* A simple tweak to pre-index the next chapter silently during normal
reading.
* Triggers silent pre-indexing of the next chapter when the penultimate
page of a chapter is rendered to reduce visible interruptions.
* Keeps existing indexing with popup when a reader jumps directly into
an unindexed chapter.
## Additional Context
* Reader input is temporarily blocked during silent indexing to avoid
navigation/index state conflicts.
* The penultimate page is used because readers typically spend longer
there than on the final page.
* This change optimizes linear reading flow while preserving reliable
indexing for non-linear navigation.
## Possible Improvements
* Add a setting for First Page Indexing vs Penultimate Page Pre-indexing
* Display an indexing icon in the status bar instead of using a popup
that overlaps book text.
Tested on device:
https://www.dropbox.com/scl/fi/29g5kjqgsi5e4hgujv38u/Silent-Indexing.MOV?rlkey=yemi4mosmev5vicaa7gpe49qw&dl=0
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**YES**_
---------
Co-authored-by: Jake Kenneally <jakekenneally@gmail.com>
## Purpose
This PR includes some preparatory changes that are needed for an
upcoming performant CJK font feature. The changes have no impact on
render time and heap allocation for latin text. **Despite this, I think
these changes stand on their own as a better font
compression/decompression implementation.**
## Summary
- Font decompressor rewrite: Replaced the 4-slot LRU group cache with a
two-tier system — a page buffer (glyphs prewarmed before rendering
begins) and a hot-group fallback (last decompressed group retained for
non-prewarmed
glyphs).
- Byte-aligned compressed bitmap format: Glyph bitmaps within compressed
groups are now stored row-padded rather than tightly packed before
DEFLATE compression, improving compression ratios by making identical
pixel rows produce
identical byte patterns. Glyphs are compacted back to packed format on
demand at render time. Reduces flash size by 155 KB.
- Page prewarm system: Added `Page::collectText` and
`Page::getDominantStyle` to extract per-style glyph requirements before
rendering, and `GfxRenderer::prewarmFontCache` to pre-decompress only
the groups needed for the dominant style
— eliminating mid-render decompression for the common case.
- UTF-8 robustness fixes: `utf8NextCodepoint` now validates continuation
bytes and returns a replacement glyph on malformed input;
`ChapterHtmlSlimParser` correctly preserves incomplete multi-byte
sequences across word-buffer flush
boundaries rather than splitting them.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**YES**_ Architecture and
design was done by me, refined a bit by Claude. Code mostly by Claude,
but not entirely.
## Summary
Extract shared reader utilities (`ReaderUtils.h`) to reduce duplication
across `EpubReaderActivity`, `TxtReaderActivity`, and (upcoming)
`MarkdownReaderActivity`.
Utilities extracted:
- `applyOrientation()` — orientation switch logic
- `detectPageTurn()` — page navigation input detection
- `renderAntiAliased()` — grayscale anti-aliasing pass
- `displayWithRefreshCycle()` — refresh mode cadence
- `GO_HOME_MS` — back button timing constant
## Impact
Flash: 32 bytes saved (6006441 → 6006409 bytes). Minimal immediate gain,
but meaningful once markdown reader and future reader types share these
functions.
Code quality: Eliminates ~100 lines of duplicated logic spread across
multiple files. All readers now follow the same patterns for
orientation, input handling, and rendering.
## Rationale
This refactor is preparation for markdown support, which requires
identical input and rendering logic. Instead of copy-pasting these
patterns a third time, all readers now share a single, tested
implementation. Future reader types can reuse `ReaderUtils` without
duplication.
---
## AI Usage
Did you use AI tools to help write this code? YES Claude extracted the
code, under my guidance. Tested on my device and seems to work fine.
## Summary: Enable footnote anchor navigation in EPUB reader
This PR extracts the core anchor-to-page mapping mechanism from PR #1143
(TOC fragment navigation) to provide immediate footnote navigation
support. By merging this focused subset first, users get a complete
footnote experience now while simplifying the eventual review and merge
of the full #1143 PR.
---
## What this extracts from PR #1143
PR #1143 implements comprehensive TOC fragment navigation for EPUBs with
multi-chapter spine files. This PR takes only the anchor resolution
infrastructure:
- Anchor-to-page mapping in section cache: During page layout,
ChapterHtmlSlimParser records which page each HTML id attribute lands
on, serializing the map into the .bin cache file.
- Anchor resolution in `EpubReaderActivity`: When navigating to a
footnote link with a fragment (e.g., `chapter2.xhtml#note1`), the reader
resolves the anchor to a page number and jumps directly to it.
- Section file format change: Bumped to version 15, adds anchor map
offset in header.
---
## Simplified scope vs. PR #1143
To minimize conflicts and complexity, this PR differs from #1143 in key
ways:
* **Anchors tracked**
* **Origin:** Only TOC anchors (passed via `std::set`)
* **This branch:** All `id` attributes
* **Page breaks**
* **Origin**: Forces new page at TOC chapter boundaries
* **This branch:** None — natural flow
* **TOC integration**
* **Origin**: `tocBoundaries`, `getTocIndexForPage()`, chapter skip
* **This branch:** None — just footnote links
* **Bug fix**
* **This branch:** Fixed anchor page off-by-1/2 bug
The anchor recording bug (recording page number before `makePages()`
flushes previous block) was identified and fixed during this extraction.
The fix uses a deferred `pendingAnchorId` pattern that records the
anchor after page completion.
---
## Positioning for future merge
Changes are structured to minimize conflicts when #1143 eventually
merges:
- `ChapterHtmlSlimParser.cpp` `startElement()`: Both branches rewrite
the same if `(!idAttr.empty())` block. The merged version will combine
both approaches (TOC anchors get page breaks + immediate recording;
footnote anchors get deferred recording).
- `EpubReaderActivity.cpp` `render()`: The `pendingAnchor` resolution
block is positioned at the exact same insertion point where #1143 places
its `pendingTocIndex` block (line 596, right after `nextPageNumber`
assignment). During merge, both blocks will sit side-by-side.
---
## Why merge separately?
1. Immediate user value: Footnote navigation works now without waiting
for the full TOC overhaul
2. Easier review: ~100 lines vs. 500+ lines in #1143
3. Bug fix included: The page recording bug is fixed here and will carry
into #1143
4. Minimal conflicts: Structured for clean merge — both PRs touch the
same files but in complementary ways
---
### AI Usage
Did you use AI tools to help write this code? _**< YES >**_ Done by
Claude Opus 4.6
## Summary
**What is the goal of this PR?**
This change avoids the pattern of creating a `std::string` using
`.substr` in order to compare against a file extension literal.
```c++
std::string path;
if (path.length() >= 4 && path.substr(path.length() - 4) == ".ext")
```
The `checkFileExtension` utility has moved from StringUtils to
FsHelpers, to be available to code in lib/. The signature now accepts a
`std::string_view` instead of `std::string`, which makes the single
implementation reusable for Arduino `String`.
Added utility functions for commonly repeated extensions.
These changes **save about 2 KB of flash (5,999,427 to 5,997,343)**.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
## Summary
**What is the goal of this PR?** Add a user setting to decide image
support: display, show placeholder instead, supress fully
Fixes#1289
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**< NO >**_
## Summary
Ref discussion:
https://github.com/crosspoint-reader/crosspoint-reader/pull/1222#discussion_r2865402110
Important note that this is a bug-for-bug fix. In reality, this branch
`WiFi.status() == WL_CONNECTED` is pretty much a dead code because the
entry point of these 2 activities don't use wifi.
It is better to refactor the management of network though, but it's
better to be a dedicated PR.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **NO**
## Summary
* Renames MyLibrary component to FileBrowser, as it better reflects what
it is, in my opinion
## Additional Context
* Frees the Library name for possible future library component that can
cache metadata, provide other ways of browsing than filesystem
structure, etc
---
### AI Usage
Did you use AI tools to help write this code? _**< YES >**_
## Summary
**What is the goal of this PR?**
Small tweaks to #1016:
- Only Activity and ActivityManager can access activityResultHandler and
activityResult
- `[[maybe_unused]]` in RenderLock constructor
- Only ActivityManager and RenderLock can access renderingMutex
- Missing renderUpdate after failed wifi selection
- Standardize on activities calling finish instead of
activityManager.popActivity
- Hold RenderLock while mutating state in EpubReaderActivity result
handlers
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
## Summary
* **What is the goal of this PR?** (e.g., Implements the new feature for
file uploading.)
- Implements auto page turn feature for epub reader in the reader
submenu
* **What changes are included?**
- added auto page turn feature in epub reader in the submenu
- currently there are 5 settings, `OFF, 1, 3, 6, 12` pages per minute
## Additional Context
* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks,
specific areas to focus on).
- Replacement PR for #723
- when auto turn is enabled, space reserved for chapter title will be
used to indicate auto page turn being active
- Back and Confirm button is used to disable it
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**Partially (mainly code
reviews)**_
## Summary
Ref comment:
https://github.com/crosspoint-reader/crosspoint-reader/pull/1010#pullrequestreview-3828854640
This PR introduces `ActivityManager`, which mirrors the same concept of
Activity in Android, where an activity represents a single screen of the
UI. The manager is responsible for launching activities, and ensuring
that only one activity is active at a time.
Main differences from Android's ActivityManager:
- No concept of Bundle or Intent extras
- No onPause/onResume, since we don't have a concept of background
activities
- onActivityResult is implemented via a callback instead of a separate
method, for simplicity
## Key changes
- Single `renderTask` shared across all activities
- No more sub-activity, we manage them using a stack; Results can be
passed via `startActivityForResult` and `setResult`
- Activity can call `finish()` to destroy themself, but the actual
deletion will be handled by `ActivityManager` to avoid `delete this`
pattern
As a bonus: the manager will automatically call `requestUpdate()` when
returning from another activity
## Example usage
**BEFORE**:
```cpp
// caller
enterNewActivity(new WifiSelectionActivity(renderer, mappedInput,
[this](const bool connected) { onWifiSelectionComplete(connected); }));
// subactivity
onComplete(true); // will eventually call exitActivity(), which deletes the caller instance (dangerous behavior)
```
**AFTER**: (mirrors the `startActivityForResult` and `setResult` from
android)
```cpp
// caller
startActivityForResult(new NetworkModeSelectionActivity(renderer, mappedInput),
[this](const ActivityResult& result) { onNetworkModeSelected(result.selectedNetworkMode); });
// subactivity
ActivityResult result;
result.isCancelled = false;
result.selectedNetworkMode = mode;
setResult(result);
finish(); // signals to ActivityManager to go back to last activity AFTER this function returns
```
TODO:
- [x] Reconsider if the `Intent` is really necessary or it should be
removed (note: it's inspired by
[Intent](https://developer.android.com/guide/components/intents-common)
from Android API) ==> I decided to keep this pattern fr clarity
- [x] Verify if behavior is still correct (i.e. back from sub-activity)
- [x] Refactor the `ActivityWithSubactivity` to just simple `Activity`
--> We are using a stack for keeping track of sub-activity now
- [x] Use single task for rendering --> avoid allocating 8KB stack per
activity
- [x] Implement the idea of [Activity
result](https://developer.android.com/training/basics/intents/result)
--> Allow sub-activity like Wifi to report back the status (connected,
failed, etc)
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **PARTIALLY**, some
repetitive migrations are done by Claude, but I'm the one how ultimately
approve it
---------
Co-authored-by: Zach Nelson <zach@zdnelson.com>
## Summary
**What is the goal of this PR?** Implement support for footnotes in epub
files.
It is based on #553, but simplified — removed the parts which
complicated the code and burden the CPU/RAM. This version supports basic
footnotes and lets the user jump from location to location inside the
epub.
**What changes are included?**
- `FootnoteEntry` struct — A small POD struct (number[24], href[64])
shared between parser, page storage, and UI.
- Parser: `<a href>` detection (`ChapterHtmlSlimParser`) — During a
single parsing pass, internal epub links are detected and collected as
footnotes. The link text is underlined to hint navigability.
Bracket/whitespace normalization is applied to the display label (e.g.
[1] → 1).
- Footnote-to-page assignment (`ChapterHtmlSlimParser`, `Page`) —
Footnotes are attached to the exact page where their anchor word
appears, tracked via a cumulative word counter during layout, surviving
paragraph splits and the 750-word mid-paragraph safety flush.
- Page serialization (`Page`, `Section`) — Footnotes are
serialized/deserialized per page (max 16 per page). Section cache
version bumped to 14 to force a clean rebuild.
- Href → spine resolution (`Epub`) — `resolveHrefToSpineIndex()` maps an
href (e.g. `chapter2.xhtml#note1`) to its spine index by filename
matching.
- Footnotes menu + activity (`EpubReaderMenuActivity`,
`EpubReaderFootnotesActivity`) — A new "Footnotes" entry in the reader
menu lists all footnote links found on the current page. The user
scrolls and selects to navigate.
- Navigate & restore (`EpubReaderActivity`) — `navigateToHref()` saves
the current spine index and page number, then jumps to the target. The
Back button restores the saved position when the user is done reading
the footnote.
**Additional Context**
**What was removed vs #553:** virtual spine items
(`addVirtualSpineItem`, `isVirtualSpineItem`), two-pass parsing,
`<aside>` content extraction to temp HTML files, `<p class="note">`
paragraph note extraction, `replaceHtmlEntities` (master already has
`lookupHtmlEntity`), `footnotePages` / `buildFilteredChapterList`,
`noterefCallback` / `Noteref` struct, and the stack size increase from 8
KB to 24 KB (not needed without two-pass parsing and virtual file I/O on
the render task).
**Performance:** Single-pass parsing. No new heap allocations in the hot
path — footnote text is collected into fixed stack buffers (char[24],
char[64]). Active runtime memory is ~2.8 KB worst-case (one page × 16
footnotes × 88 bytes, mirrored in `currentPageFootnotes`). Flash usage
is unchanged at 97.4%; RAM stays at 31%.
**Known limitations:** When clicking a footnote, it jumps to the start
of the HTML file instead of the specific anchor. This could be
problematic for books that don't have separate files for each footnote.
(no element-id-to-page mapping yet - will be another PR soon).
---
### AI Usage
Did you use AI tools to help write this code? _**< PARTIALLY>**_
Claude Opus 4.6 was used to do most of the migration, I checked manually
its work, and fixed some stuff, but I haven't review all the changes
yet, so feedback is welcomed.
---------
Co-authored-by: Arthur Tazhitdinov <lisnake@gmail.com>
## Summary
* **What is the goal of this PR?** KOReader sync on a German-language
book would fail with an out-of-memory error when trying to open the
destination chapter after applying remote progress. The root cause was a
chain of two independent bugs that combined to exhaust the contiguous
heap needed by the EPUB inflate pipeline.
* **What changes are included?**
## Fix 1 — Hyphenation heap defragmentation (LiangHyphenation.cpp)
### What was happening
AugmentedWord, the internal struct used during Liang pattern matching,
held three std::vector<> members (bytes, charByteOffsets,
byteToCharIndex) plus a separate scores vector — a total of 4 heap
allocations per word during page layout. For a German-language section
with hundreds of words, thousands of small malloc/free cycles fragmented
the heap. Total free memory was adequate (~108 KB) but the largest
contiguous block shrank well below the 32 KB needed for the INFLATE ring
buffer used during EPUB decompression. The failure was invisible with
hyphenation disabled, where MaxAlloc stayed at ~77 KB; enabling German
hyphenation silently destroyed the contiguity the allocator needed.
### What changed
The three std::vector<> members of AugmentedWord and the scores vector
are replaced with fixed-size C arrays on the render-task stack:
```
uint8_t bytes[160] // was std::vector<uint8_t>
size_t charByteOffsets[70] // was std::vector<size_t>
int32_t byteToCharIndex[160] // was std::vector<int32_t>
uint8_t scores[70] // was std::vector<uint8_t> (local in liangBreakIndexes)
```
Sizing is based on the longest known German word (~63 codepoints × 2
UTF-8 bytes + 2 sentinel dots = 128 bytes); MAX_WORD_BYTES=160 and
MAX_WORD_CHARS=70 give comfortable headroom. The same analysis holds for
all seven supported languages (en, fr, de, es, it, ru, uk) — every
accepted letter encodes to at most 2 UTF-8 bytes after case-folding.
Words exceeding the limits are silently skipped (no hyphenation
applied), which is correct behaviour. The struct lives on the 8 KB
render-task stack so no permanent DRAM is consumed.
Verification: after the fix, MaxAlloc reads 77,812 bytes with German
hyphenation enabled — identical to the figure previously achievable only
with hyphenation off.
## Fix 2 — WiFi lifecycle in KOReaderSyncActivity
(KOReaderSyncActivity.cpp)
### What was happening
onEnter() called WiFi.mode(WIFI_STA) unconditionally before delegating
to WifiSelectionActivity. WifiSelectionActivity manages WiFi mode
internally (it calls WiFi.mode(WIFI_STA) again at scan start and at
connection attempt). The pre-emptive call from KOReaderSyncActivity
interfered with the sub-activity's own state machine, causing
intermittent connection failures that were difficult to reproduce.
Additionally, WiFi was only shut down in onExit(). If the user chose
"Apply remote progress" the activity exited without turning WiFi off
first, leaving the radio on and its memory allocated while the EPUB was
being decompressed — unnecessarily consuming the contiguous heap
headroom that inflate needed.
### What changed
* WiFi.mode(WIFI_STA) removed from onEnter(). WifiSelectionActivity owns
WiFi mode; KOReaderSyncActivity should not touch it before the
sub-activity runs.
* A wifiOff() helper (SNTP stop + disconnect + WIFI_OFF with settling
delays) is extracted into the anonymous namespace and called at every
web-session exit point:
- "Apply remote" path in loop() — before onSyncComplete()
- performUpload() success path
- performUpload() failure path
- onExit() (safety net for all other exit paths)
## Additional Context
* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks,
specific areas to focus on).
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**YES**_ and two days of
blood, sweat and heavy swearing...
## Summary
This PR aims to reduce the complexity of the status bar by splitting the
setting into 5:
- Chapter Page Count
- Book Progress %
- Progress Bar
- Chapter Title
- Battery Indicator
These are located within the new StausBarSettings activity, which also
shows a preview of the bar the user has created
<img width="513" height="806" alt="image"
src="https://github.com/user-attachments/assets/cdf852fb-15d8-4da2-a74f-fd69294d7b05"
/>
<img width="483" height="797" alt="image"
src="https://github.com/user-attachments/assets/66fc0c0d-ee51-4d31-b70d-e2bc043205d1"
/>
When updating from a previous version, the user's past settings are
honoured.
## Additional Context
The PR aims to remove any duplication of status bar code where possible,
and extracts the status bar rendering into a new component - StatusBar
It also adds a new (optional) padding option to the progress bar to
allow the status bar to be shifted upwards - this is only intended for
use in the settings.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code?
No - although did help to decode some C++ errors
---------
Co-authored-by: Arthur Tazhitdinov <lisnake@gmail.com>
## Summary
**What is the goal of this PR?**
Small cleanup to make getTheme and getMetrics methods on UITheme const.
They return const refs, so updated call sites to use `const auto&`.
Realistically this won't make much performance difference, but it better
conveys the nature of theme metrics being shared const state.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
## Summary
* **What is the goal of this PR?** (e.g., Implements the new feature for
file uploading.)
Implements new feature for viewing .bmp files directly from the "Browse
Files" menu.
* **What changes are included?**
You can now view .bmp files when browsing. You can click the select
button to open the file, and then click back to close it and continue
browsing in the same location. Once open a file will display on the
screen with no additional options to interact outside of exiting with
the back button.
The attached video shows this feature in action:
https://github.com/user-attachments/assets/9659b6da-abf7-4458-b158-e11c248c8bef
## Additional Context
* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks,
specific areas to focus on).
The changes implemented in #884 are also present here as this feature is
actually what led to me noticing this issue. I figured I would add that
PR as a separate request in case that one could be more easily merged
given this feature is significantly more complicated and will likely be
subject to more intense review.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **YES**
---------
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
## Summary
Fixes https://github.com/crosspoint-reader/crosspoint-reader/issues/1011
Use double FAST_REFRESH for image pages to prevent grayscale washout,
HALF_REFRESH sets e-ink particles too firmly for the grayscale LUT to
adjust, causing washed-out images (especially large, light-gray ones).
Replace HALF_REFRESH with @pablohc's double FAST_REFRESH technique:
blank only the image bounding box area, then re-render with images. This
clears ghosting while keeping particles loosely set for grayscale.
## Additional Context
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**< PARTIALLY >**_
## Summary
1. Go to the first page in a .epub file.
2. Hit `Up` button
3. Get teleported to the last page :)
`TxtRenderActivity` seems to have this if check, but EPUB one does not.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
## Summary
* Original implementation had inconsistent positioning logic:
- When XPath parsing succeeded: incorrectly set pageNumber = 0 (always
beginning of chapter)
- When XPath parsing failed: used percentage for positioning (worked
correctly)
- Result: Positions restored to wrong locations depending on XPath
parsing success
- Mentioned in Issue #581
* Solution
- Unified ProgressMapper::toCrossPoint() to use percentage-based
positioning exclusively for both spine identification and intra-chapter
page calculation, eliminating unreliable XPath parsing entirely.
## Additional Context
* ProgressMapper.cpp: Simplified toCrossPoint() to always use percentage
for positioning, removed parseDocFragmentIndex() function
* ProgressMapper.h: Updated comments and removed unused function
declaration
* Tests confirmed appropriate positioning
* __Notabene: the syncing to another device will (most probably) end up
at the current chapter of crosspoints reading position. There is not
much we can do about it, as KOReader needs to have the correct XPath
information - we can only provide an apporximate position (plus
percentage) - the percentage information is not used in KOReaders
current implementation__
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? YES
## Summary
**What is the goal of this PR?**
Compress reader font bitmaps to reduce flash usage by 30.7%.
**What changes are included?**
- New `EpdFontGroup` struct and extended `EpdFontData` with
`groups`/`groupCount` fields
- `--compress` flag in `fontconvert.py`: groups glyphs (ASCII base group
+ groups of 8) and compresses each with raw DEFLATE
- `FontDecompressor` class with 4-slot LRU cache for on-demand
decompression during rendering
- `GfxRenderer` transparently routes bitmap access through
`getGlyphBitmap()` (compressed or direct flash)
- Uses `uzlib` for decompression with minimal heap overhead.
- 48 reader fonts (Bookerly, NotoSans 12-18pt, OpenDyslexic) regenerated
with compression; 5 UI fonts unchanged
- Round-trip verification script (`verify_compression.py`) runs as part
of font generation
## Additional Context
## Flash & RAM
| | baseline | font-compression | Difference |
|--|--------|-----------------|------------|
| Flash (ELF) | 6,302,476 B (96.2%) | 4,365,022 B (66.6%) | -1,937,454 B
(-30.7%) |
| firmware.bin | 6,468,192 B | 4,531,008 B | -1,937,184 B (-29.9%) |
| RAM | 101,700 B (31.0%) | 103,076 B (31.5%) | +1,376 B (+0.5%) |
## Script-Based Grouping (Cold Cache)
Comparison of uncompressed baseline vs script-based group compression
(4-slot LRU cache, cleared each page). Glyphs are grouped by Unicode
block (ASCII, Latin-1, Latin Extended-A, Combining Marks, Cyrillic,
General Punctuation, etc.) instead of sequential groups of 8.
### Render Time
| | Baseline | Compressed (cold cache) | Difference |
|---|---|---|---|
| **Median** | 414.9 ms | 431.6 ms | +16.7 ms (+4.0%) |
| **Pages** | 37 | 37 | |
### Memory Usage
| | Baseline | Compressed (cold cache) | Difference |
|---|---|---|---|
| **Heap free (median)** | 187.0 KB | 176.3 KB | -10.7 KB |
| **Heap free (min)** | 186.0 KB | 166.5 KB | -19.5 KB |
| **Largest block (median)** | 148.0 KB | 128.0 KB | -20.0 KB |
| **Largest block (min)** | 148.0 KB | 120.0 KB | -28.0 KB |
### Cache Effectiveness
| | Misses/page | Hit rate |
|---|---|---|
| **Compressed (cold cache)** | 2.1 | 99.85% |
------
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**YES**_
Implementation was done by Claude Code (Opus 4.6) based on a plan
developed collaboratively. All generated font headers were verified with
an automated round-trip decompression test. The firmware was compiled
successfully but has not yet been tested on-device.
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
## Summary
**What is the goal of this PR?**
In some places, button labels are omitted intentionally because the
button has no purpose in the activity. I noticed a few obvious cases,
like Home > File Transfer and Settings > System > Language, where the up
and down button labels were missing. This change fixes those and all
similar instances I could find.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
Issues solved: #729 and #739
## Summary
* **What is the goal of this PR?**
Currently, the battery icon and charge percentage were aligned to the
left even for the UI, where they were positioned on the right side of
the screen. This meant that when changing values of different numbers of
digits, the battery would shift, creating a block of icons and text that
was illegible.
* **What changes are included?**
- Add drawBatteryUi() method for right-aligned battery display in UI
headers
- Keep drawBattery() for left-aligned display in reader mode
- Extract drawBatteryIcon() helper to reduce code duplication
- Battery icon now stays fixed at right edge regardless of percentage
digits
- Text adjusts to left of icon in UI mode, to right of icon in reader
mode
## Additional Context
* Add any other information that might be helpful for the reviewer
* This fix applies to both themes (Base and Lyra).
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**< YES >**_
## Summary
**What is the goal of this PR?**
This PR introduces Internationalization (i18n) support, enabling users
to switch the UI language dynamically.
**What changes are included?**
- Core Logic: Added I18n class (`lib/I18n/I18n.h/cpp`) to manage
language state and string retrieval.
- Data Structures:
- `lib/I18n/I18nStrings.h/cpp`: Static string arrays for each supported
language.
- `lib/I18n/I18nKeys.h`: Enum definitions for type-safe string access.
- `lib/I18n/translations.csv`: single source of truth.
- Documentation: Added `docs/i18n.md` detailing the workflow for
developers and translators.
- New Settings activity:
`src/activities/settings/LanguageSelectActivity.h/cpp`
## Additional Context
This implementation (building on concepts from #505) prioritizes
performance and memory efficiency.
The core approach is to store all localized strings for each language in
dedicated arrays and access them via enums. This provides O(1) access
with zero runtime overhead, and avoids the heap allocations, hashing,
and collision handling required by `std::map` or `std::unordered_map`.
The main trade-off is that enums and string arrays must remain perfectly
synchronized—any mismatch would result in incorrect strings being
displayed in the UI.
To eliminate this risk, I added a Python script that automatically
generates `I18nStrings.h/.cpp` and `I18nKeys.h` from a CSV file, which
will serve as the single source of truth for all translations. The full
design and workflow are documented in `docs/i18n.md`.
### Next Steps
- [x] Python script `generate_i18n.py` to auto-generate C++ files from
CSV
- [x] Populate translations.csv with initial translations.
Currently available translations: English, Español, Français, Deutsch,
Čeština, Português (Brasil), Русский, Svenska.
Thanks, community!
**Status:** EDIT: ready to be merged.
As a proof of concept, the SPANISH strings currently mirror the English
ones, but are fully uppercased.
---
### AI Usage
Did you use AI tools to help write this code? _**< PARTIALLY >**_
I used AI for the black work of replacing strings with I18n references
across the project, and for generating the documentation. EDIT: also
some help with merging changes from master.
---------
Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
Co-authored-by: yeyeto2788 <juanernestobiondi@gmail.com>
## Summary
Follow-up to
https://github.com/crosspoint-reader/crosspoint-reader/pull/774
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **NO**
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Release Notes
* **Refactor**
* Modernized internal synchronization mechanisms across multiple
components to improve code reliability and maintainability. All
functionality remains unchanged.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
## Summary
Currently, each activity has to manage their own `displayTaskLoop` which
adds redundant boilerplate code. The loop is a wait loop which is also
not the best practice, as the `updateRequested` boolean is not protected
by a mutex.
In this PR:
- Move `displayTaskLoop` to the super `Activity` class
- Replace `updateRequested` with freeRTOS's [direct to task
notification](https://www.freertos.org/Documentation/02-Kernel/02-Kernel-features/03-Direct-to-task-notifications/01-Task-notifications)
- For `ActivityWithSubactivity`, whenever a sub-activity is present, the
parent's `render()` automatically goes inactive
With this change, activities now only need to expose `render()`
function, and anywhere in the code base can call `requestUpdate()` to
request a new rendering pass.
## Additional Context
In theory, this change may also make the battery life a bit better,
since one wait loop is removed. Although the equipment in my home lab
wasn't been able to verify it (the electric current is too noisy and
small). Would appreciate if anyone has any insights on this subject.
Update: I managed to hack [a small piece of
code](https://github.com/ngxson/crosspoint-reader/tree/xsn/measure_cpu_usage)
that allow tracking CPU idle time.
The CPU load does decrease a bit (1.47% down to 1.39%), which make
sense, because the display task is now sleeping most of the time unless
notified. This should translate to a slightly increase in battery life
in the long run.
```
PR:
[40012] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[40012] [IDLE] Idle time: 98.61% (CPU load: 1.39%)
[50017] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[50017] [IDLE] Idle time: 98.61% (CPU load: 1.39%)
[60022] [MEM] Free: 185856 bytes, Total: 231004 bytes, Min Free: 123316 bytes
[60022] [IDLE] Idle time: 98.61% (CPU load: 1.39%)
master:
[20012] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[20012] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
[30017] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[30017] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
[40022] [MEM] Free: 195016 bytes, Total: 231532 bytes, Min Free: 132460 bytes
[40022] [IDLE] Idle time: 98.53% (CPU load: 1.47%)
```
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **NO**
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Refactor**
* Streamlined rendering architecture by consolidating update mechanisms
across all activities, improving efficiency and consistency.
* Modernized synchronization patterns for display updates to ensure
reliable, conflict-free rendering.
* **Bug Fixes**
* Enhanced rendering stability through improved locking mechanisms and
explicit update requests.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
---------
Co-authored-by: znelson <znelson@users.noreply.github.com>
## Summary
- Add embedded image support to EPUB rendering with JPEG and PNG
decoders
- Implement pixel caching system to cache decoded/dithered images to SD
card for faster re-rendering
- Add 4-level grayscale support for display
## Changes
### New Image Rendering System
- Add `ImageBlock` class to represent an image with its cached path and
display dimensions
- Add `PageImage` class as a new `PageElement` type for images on pages
- Add `ImageToFramebufferDecoder` interface for format-specific image
decoders
- Add `JpegToFramebufferConverter` - JPEG decoder with Bayer dithering
and scaling
- Add `PngToFramebufferConverter` - PNG decoder with Bayer dithering and
scaling
- Add `ImageDecoderFactory` to select appropriate decoder based on file
extension
- Add `getRenderMode()` to GfxRenderer for grayscale render mode queries
### Dithering and Grayscale
- Implement 4x4 Bayer ordered dithering for 4-level grayscale output
- Stateless algorithm works correctly with MCU block decoding
- Handles scaling without artifacts
- Add grayscale render mode support (BW, GRAYSCALE_LSB, GRAYSCALE_MSB)
- Image decoders and cache renderer respect current render mode
- Enables proper 4-level e-ink grayscale when anti-aliasing is enabled
### Pixel Caching
- Cache decoded/dithered images to `.pxc` files on SD card
- Cache format: 2-bit packed pixels (4 pixels per byte) with
width/height header
- On subsequent renders, load directly from cache instead of re-decoding
- Cache renderer supports grayscale render modes for multi-pass
rendering
- Significantly improves page navigation speed for image-heavy EPUBs
### HTML Parser Integration
- Update `ChapterHtmlSlimParser` to process `<img>` tags and extract
images from EPUB
- Resolve relative image paths within EPUB ZIP structure
- Extract images to cache directory before decoding
- Create `PageImage` elements with proper scaling to fit viewport
- Fall back to alt text display if image processing fails
### Build Configuration
- Add `PNG_MAX_BUFFERED_PIXELS=6402` to support up to 800px wide images
### Test Script
- Generate test EPUBs with annotated JPEG and PNG images
- Test cases cover: grayscale (4 levels), centering, scaling, cache
performance
## Test plan
- [x] Open EPUB with JPEG images - verify images display with proper
grayscale
- [x] Open EPUB with PNG images - verify images display correctly and no
crash
- [x] Navigate away from image page and back - verify faster load from
cache
- [x] Verify grayscale tones render correctly (not just black/white
dithering)
- [x] Verify large images are scaled down to fit screen
- [x] Verify images are centered horizontally
- [x] Verify page serialization/deserialization works with images
- [x] Verify images rendered in landscape mode
## Test Results
[png](https://photos.app.goo.gl/5zFUb8xA8db3dPd19)
[jpeg](https://photos.app.goo.gl/SwtwaL2DSQwKybhw7)








---
### AI Usage
Did you use AI tools to help write this code? _**< YES >**_
---------
Co-authored-by: Matthías Páll Gissurarson <mpg@mpg.is>
Co-authored-by: Dave Allie <dave@daveallie.com>
## Summary
Closes#766. Thank you for the help @bramschulting!
**What is the goal of this PR?**
- First and foremost, fix issue #766.
- Through working on that, I realized the current CSS parsing/loading
code can be improved dramatically for large files and still had
additional performance improvements to be made, even with EPUBs with
small CSS.
**What changes are included?**
- Stream CSS parsing and reuse normalization buffers to cut allocations
- Add rule limits and selector validation to release rules and free up
memory when needed
- Skip CSS parsing/loading entirely when "Book's Embedded Style" is off
## Additional Context
- My test EPUB has been updated
[here](https://github.com/jdk2pq/css-test-epub) to include a very large
CSS file to test this out
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**YES**_, Codex