Chapter selection previously only used the spine index, causing
navigation to always land on page 0 of the spine item. Sub-chapters that
share a spine file but differ by anchor (e.g. `chapter.xhtml#sec2`) were
silently ignored. Now the TOC anchor is passed through `ChapterResult`
and applied via the existing `pendingAnchor` mechanism.
## Summary
* This PR implements navigation to sub-chapters which didn't work
correctly previously. If a sub-chapter of the current top-level chapter
was selected, nothing happened. If a sub-chapter of another top-level
chapter was selected, reader switched to the beginning of the top-level
chapter.
* In addition, chapters now always start from a new page. This fixes
anchor to page calculation for the cases when the actual chapter content
doesn't fit on the page where the corresponding ToC anchor was found.
## Additional Context
* I might misuse `pendingAnchor` here which was previously used for
footnote navigation, please double check. I'm open to suggestions for
improvements.
* Note that the chapter selected by default when
`EpubReaderChapterSelectionActivity` opens is still wrong. I'm going to
fix this separately. This PR addresses only navigation to the selected
chapter.
* I tested this PR on my X4 and verified that navigation to a different
sub-chapter works correctly, both inside and outside the current spine.
* Some of the changes were borrowed from
https://github.com/crosspoint-reader/crosspoint-reader/pull/1455
---
### AI Usage
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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**_
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Tiled grayscale rendering to drop the storeBwBuffer peak largest
contiguous free block (the value that actually drives OOM on the C3)
from ~114 KB to ~82-90 KB.
This renders each grayscale plane band-by-band into a small (~8 KB)
scratch and
streams each band straight to controller RAM (community-sdk
writeGrayscalePlaneStrip), leaving the BW framebuffer intact. No save,
no
restore; controller RAM is re-synced for the next differential turn
directly
from the live framebuffer.
Three writers honor the active band target so per-band re-rendering
stays cheap
and correct:
- drawPixel (text) redirects writes to the band scratch and clips to it.
- renderCharImpl skips glyphs whose physical y-extent is outside the
band before
the bitmap decode (glyphIntersectsStrip), so the per-band re-render
doesn't
pay N x glyph decode.
- DirectPixelWriter (images) writes the band scratch via getWriteTarget
instead
of the framebuffer. Without this, image pixels wrote the live BW frame
directly and cleanup re-synced that corruption, leaving thin outlines
after
navigating away from an image.
Controller specifics live in the SDK (X4 setRamArea windowing, X3 PTL);
the
reader checks supportsStripGrayscale() and is otherwise
controller-agnostic.
Measured on hardware (X4 and X3, text and images, visually correct):
- Grayscale scratch ~8 KB vs ~50 KB save; largest contiguous free block
held at
full size during grayscale instead of dropping ~25-32 KB.
- X4 text page about +25 ms/page; X3 page time is dominated by its
intrinsic
grayscale refresh, not tiling.
Depends on community-sdk #13 (the writeGrayscalePlaneStrip API). The
submodule
bump here points at that branch, so until #13 merges the submodule won't
resolve
from upstream and CI will fail there; keeping this a draft until then.
Will
rebase onto master and re-point the submodule to the merged SDK commit
once #13
lands.
Did you use AI tools to help write this code? partial
## Summary
* Add swedish hyphenation using scripts/update_hypenation.sh
* Add hyphenation test data using the Swedish translation of Andy Weir's
Project Hail Mary
---
### AI Usage
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please be transparent about their usage as it
helps set the right context for reviewers.
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## Summary
SD card font fixes:
- `TxtReaderActivity` needs to call `renderer.ensureSdCardFontReady` to
build the advance lookup table to support rendering with SD card fonts.
This revealed that `TxtReaderActivity` was inconsistently performing
layout with `getTextWidth`, when the renderer actually uses
`getTextAdvanceX`, which can lead to minor inconsistencies in alignment.
- Avoid allocating one big `allText` string in
`ParsedText::layoutAndExtractLines`. Instead, pass the vector of word
strings directly to `SdCardFont::buildAdvanceTable`, where the algorithm
just needs to iterate codepoints anyway.
---
### AI Usage
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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**_
---------
Co-authored-by: Justin Mitchell <justin@jmitch.com>
## Summary
Relative includes can hide inappropriate dependency relationships. In
this case, I found that lib/KOReaderSync/KOReaderCredentialStore.cpp was
dependent on src/JsonSettingsIO.h -- a lib -> app dependency, the
opposite direction dependencies should flow in this project.
This change replaces all relative includes with root-relative includes,
and corrects the KOReaderCredentialStore dependency by moving its JSON
settings serialization local to the KOReaderSync library.
---
### 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
This PR introduces **Focus Reading**, a generic implementation of
artificial fixation points (similar to Bionic Reading) designed to
improve reading speed and focus by bolding the initial characters of
words. This is achieved by dynamically bolding characters during
indexing.
<img width="500" alt="Focus Reading on X3"
src="https://github.com/user-attachments/assets/94a632a5-82da-47be-957c-538b35bf84d9"
/>
### Implementation Details
#### Core Text Engine (`ParsedText`)
- Modified `ParsedText::addWord` to implement a custom bolding
algorithm. It uses a 45% ratio for bolding, with a minimum of 1
character and a maximum of 9.
- UTF-8 Safety: Integrated `utf8NextCodepoint` to ensure character
counting and string slicing occur at safe byte boundaries, preventing
corruption of multi-byte characters (e.g., accented letters or smart
quotes).
- Intelligent Tokenization: This correctly identifies and separates
"word" characters (letters, apostrophes, hyphens) from "non-word"
characters (numbers, brackets, smart quotes).
- Formatting Preservation: The logic ensures that punctuation is not
"stolen" for the bolding count and that existing styles (like italics or
underlines) are preserved across the bold/regular split.
- Processing at indexing stage reduces CPU load at render-time and
ensures layout/fit is unaffected.
- Split details are tracked with `wordIsFocusSuffix`. After splitting
and layout, suffixes are merged back into their preceding word entries
to prevent a doubling of RAM usage.
#### Settings and UI
- Version Management: Bumped `SECTION_FILE_VERSION` to `21`
- Global Settings: Added `focusReadingEnabled` to `CrossPointSettings`.
- User Interface: Added a new toggle in the "Reader" section of the
settings menu, positioned after the "Embedded Style" option.
- Localization: Added the `STR_FOCUS_READING` string
#### Plumbing
- Plumbed the `focusReadingEnabled` boolean through
`EpubReaderActivity`, `Section`, and `ChapterHtmlSlimParser` to ensure
the user's setting reaches the `ParsedText` constructor during chapter
indexing.
## Additional Context
### Files Changed
- `lib/Epub/Epub/ParsedText.h / .cpp`: Core fixation logic and UTF-8
tokenization.
- `lib/Epub/Epub/Section.h / .cpp`: Cache header updates and
invalidation logic.
- `lib/Epub/Epub/parsers/ChapterHtmlSlimParser.h / .cpp`: Plumbing the
setting to text blocks.
- `src/CrossPointSettings.h`: Data persistence for the new setting.
- `src/SettingsList.h`: UI toggle implementation.
- `src/activities/reader/EpubReaderActivity.cpp`: Handling settings
changes during reading sessions.
- `lib/I18n/translations/*.yaml`: UI strings.
---
### AI Usage
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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
**Goal:** Fix bidirectional KOSync position matching between CrossPoint
and KOReader so that syncing in either direction lands on the correct
page with character-level accuracy.
**Changes included:**
**Download — `toCrossPoint` (server XPath → CrossPoint page)**
- **XPath ancestry mode for structured elements**: The previous
`ParagraphStreamer` only tracked `<p>` elements. Replaced with a full
ancestor-walking mode that correctly resolves XPaths pointing into
`<li>`, `<ul>`, and other structured elements. Char offset within the
target element is bounded to the matched element's content only.
- **Slash-in-attribute-value corrupts depth tracking**:
`processByteInTag()` treated every `/` byte as a self-closing tag
marker, including `/` inside quoted attribute values (e.g.
`xmlns="http://..."`, `src="Links/image.jpg"`). This drove `htmlDepth`
to 0 prematurely, causing the ancestry search to exit far short of the
target paragraph. Fixed with `inAttrQuote` tracking.
- **Off-by-one in page formula**: `intra * totalPages` rounds up
incorrectly for last-page positions. Changed to `intra * (totalPages -
1)` to map the `[0, 1]` intra fraction correctly onto the `[0,
totalPages-1]` page range. Example: page 14 of 17 was returned as 15.
**Upload — `toKOReader` (CrossPoint page → server XPath)**
- **Off-by-one in page-to-intra formula**: Symmetric fix — `pageNumber /
totalPages` changed to `pageNumber / (totalPages - 1)`, with the guard
updated from `> 0` to `> 1` to avoid division by zero.
- **`<li>`-based XPath generation**: When the current page starts on a
list item, `findXPathForProgress` now generates `ul[N]/li[M]` XPaths
rather than falling back to the preceding `<p>`. Requires the new
`listItemIndex` field in `PageLutEntry` (section cache version bumped to
23).
- **Text-node precision with correct `text()[N].M` format**: KOReader
expects `text()[N].M` where `N` is the 1-based index of the specific
text node within the element. The previous attempt generated `text().M`
(no brackets), which caused KOReader to jump to the front of the book.
Implements a per-element text-node index stack in
`XPathProgressResolver` — parallel to the existing element path stack —
that correctly tracks text node indices relative to each element. Empty
text nodes from bare anchor elements (`<a id="anchor"/>`) are
intentionally skipped, matching KOReader's own text node counting
behavior.
**Reviewer-caught bugs**
- **Double `onCloseTag()` on malformed `</br/>`**: Both the `tagIsClose`
path and the self-closing `/` check were firing, double-decrementing
`htmlDepth`. Fixed with a `!tagIsClose` guard.
- **Dangling pointer in `LOG_DBG`**:
`std::to_string(*nextParagraphPage).c_str()` passed a pointer to a
temporary destroyed before the variadic call. Fixed with `snprintf` into
a stack `char[8]` buffer.
## Additional Context
- Section cache version bumped from 22 → 23 due to the new
`listItemIndex` field in `PageLutEntry`. Users upgrading will see a
one-time re-render of all cached sections on first load — no data loss.
- The `textNodeIndexStack` in `XPathProgressResolver` is a
`std::vector<int>` that mirrors the existing `path` and `parentStates`
stacks — same depth, same lifetime. No additional heap pressure beyond
what was already present.
- All fixes verified on device with *Gentle and Lowly* by Dane C.
Ortlund (spine 21, 17 pages). Download syncs land on the correct page;
upload syncs land at the correct paragraph with character-level offset.
## Test plan
- [ ] Download: sync from KOReader → CrossPoint lands on correct page
for `text()[N].M` XPaths
- [ ] Download: ancestry correctly resolves `<li>` positions inbound
from KOReader
- [ ] Upload: sync from CrossPoint → KOReader lands within one page for
mid-paragraph positions
- [ ] Upload: sync from CrossPoint → KOReader correctly targets `<li>`
elements when page starts on a list item
- [ ] Upload: `text()[N].M` format XPaths do not cause KOReader to jump
to front of book
- [ ] Section cache version 23: delete `.crosspoint/` and verify clean
re-parse with no crashes
---
### AI Usage
Did you use AI tools to help write this code? **YES** — developed with
Claude Code (Anthropic).
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Add a complete SD card font subsystem that enables users to install and
use custom fonts beyond the three built-in families. This combines the
back-end firmware support (#1327) with the font configuration, build
pipeline, CI distribution, and user-facing management UI (#1392).
Core font system:
- Custom .cpfont binary format (v4) with multi-style support (regular,
bold, italic, bold-italic) packed into a single file per size
- On-demand glyph loading from SD card with two-pass prewarm rendering
to bulk-read glyphs per page, achieving near-flash performance for
Latin text (~697ms vs ~681ms) and viable CJK rendering (~32% slower)
- Persistent advance cache for layout measurement without SD I/O
- Overflow ring buffer for glyph cache misses during rendering
- Memory-conscious design: only advance tables kept in RAM; glyph
bitmaps, kern tables, and ligatures loaded on demand from SD
Font management:
- On-device WiFi download from GitHub Releases with manifest-based
discovery, install/update detection, and progress UI
- Web interface font upload, listing, and deletion via /fonts page
- Manual SD card copy to /fonts/ or /.fonts/ directories
- Font selection integrated into Settings > Reader > Font Family
Build pipeline:
- Declarative YAML config (sd-fonts.yaml) as single source of truth
for the 17-family font library (serif, sans, mono, accessibility)
- Python converter (fontconvert_sdcard.py) for TTF/OTF to .cpfont with
FreeType rasterization, class-based kerning, and ligature extraction
- Parallel build orchestrator with variable font instance extraction
- CI workflow publishing versioned + stable releases to a dedicated
crosspoint-fonts repository with auto-incrementing revision tags
- Centralized version constants (cpfont_version.py) shared across
build tooling and CI, with firmware headers as manual sync points
Additional fixes:
- CJK characters no longer get hyphens inserted at line breaks
- Advance table eliminates 30+ second stalls during CJK section
indexing for paragraphs with >512 unique codepoints
Closes#930
Co-authored-by: Zach Nelson <zach@zdnelson.com>
Co-authored-by: Justin <itsthisjustin@users.noreply.github.com>
Co-authored-by: jpirnay <jens@pirnay.com>
Co-authored-by: mcrosson <kemonine@kemonine.info>
## Summary
* **What is the goal of this PR?**
Fixes a bug in the jpeg nearest-neighbor downscaler where source image
rows containing visible content may be cropped.
* **What changes are included?**
Split the single `fineScaleFP`/`invScaleFP` scale pair in
`JpegToFramebufferConverter.cpp` into separate X
(`fineScaleFPX`/`invScaleFPX`) and Y (`fineScaleFPY`/`invScaleFPY`)
pairs
## Additional Context
The one case that I encountered in my epub:
<img width="480" height="37" alt="img_6_0"
src="https://github.com/user-attachments/assets/0de3778c-cf3d-42dc-a1ba-4ba729f6b1c4"
/>
The image generated from pxc cache with the latest commit:
<img width="464" height="36" alt="img_6_0_master pxc"
src="https://github.com/user-attachments/assets/92ba06e5-be15-4db6-840e-882bdddb1baf"
/>
With this fix, the bottom outline of each character is still there:
<img width="464" height="36" alt="img_6_0_fixed pxc"
src="https://github.com/user-attachments/assets/4246ce55-5a20-480f-862f-7988f804c1fb"
/>
---
### AI Usage
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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
Simplify code calculating compile-time array sizes with
`sizeof(array)/sizeof(element)` to use `std::size`.
---
### AI Usage
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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
* Add new block style stack to track accumulated styles
* When dropping into nested block, apply new styles on last BlockStyle
in the stack and push to the back
* When leaving block, pop the stack
* Fix issue where the image % width always went off screen width, use
current container width based on accumulated styles
* Bump section cache version to regenerate pages
## Additional Context
Fixes https://github.com/crosspoint-reader/crosspoint-reader/pull/1581
more correctly, and includes fix from
https://github.com/crosspoint-reader/crosspoint-reader/pull/1580
Consider:
```html
<div class="c1"> <!-- marginLeft: 10px -->
<div class="c2"> <!-- marginLeft: 20px -->
<p class="c3">text</p> <!-- marginLeft: 5px -->
</div>
<p class="c4">text2</p> <!-- marginLeft: 5px -->
</div>
```
| Element | Expected | Before #1581 (leaked) | After #1581 (reset) |
This PR (style stack) |
| --- | --- | --- | --- | --- |
| `c3` | 10+20+5 = 35px | 35px | 25px | 35px |
| `c4` | 10+5 = 15px | 35px (wrong, leaked c2) | 5px (wrong, lost c1) |
15px |
This PR replaces the reset-on-close approach with a proper block style
stack. When a block element opens, its resolved style is pushed onto the
stack. When it closes, the stack pops back to the parent's style. This
correctly accumulates nested margins/padding while preventing style
leakage to siblings.
---
### 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: Zach Nelson <zach@zdnelson.com>
## Summary
- **What is the goal of this PR?** Fix chapter-opener text collapsing to
1-2 words per line in EPUBs that apply large em-based horizontal CSS
insets.
- **What changes are included?** Caps `marginLeft`, `marginRight`,
`paddingLeft`, and `paddingRight` at 2em in `BlockStyle::fromCssStyle`
(`lib/Epub/Epub/blocks/BlockStyle.h`). Vertical margins/padding are
unchanged - the bug is horizontal-only.
## Additional Context
**Repro:** *Mother Night* by Kurt Vonnegut, Chapter 21 ("My best
friend..."). The chapter-opening element's embedded CSS sets a large
horizontal inset.
- Settings: Embedded Style = On, Justify alignment (default).
- Before: 1-2 words per line with a visible river between them.
- After: body text fills the usable page width like every other
paragraph.
**Why the clamp lives in `fromCssStyle`:** This is the single point
where CSS lengths resolve to pixels, so clamping here keeps both
`effectiveWidth` call sites in `ChapterHtmlSlimParser` (`:1131-1133`
makePages, `:841-844` long-block split) consistent with the
`leftInset()` xOffset. A width-only clamp at either call site would
leave text pushed right by a large xOffset.
**Test plan:**
- [x] Flashed to Xteink X4. Chapter 21 of *Mother Night* renders
normally with Embedded Style on.
- Users with cached layouts of affected books need to delete
`.crosspoint/epub_<hash>/sections/` (or the whole `.crosspoint/`) on the
SD card to pick up the fix.
**Before / After:**
<p float="left">
<img height="400" alt="IMG_0320"
src="https://github.com/user-attachments/assets/de8815ae-f2f4-4845-be1f-449c5a25d191"
/>
<img height="400" alt="IMG_0324"
src="https://github.com/user-attachments/assets/95f5f4cb-8aa1-418e-b611-18e0c342cbef"
/>
</p>
---
### 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 >**_
I used Claude Code (Opus 4.7) to evaluate the codebase and find the
relevant code related to this rendering. From there, it was human
designed, reviewed and tested.
Co-authored-by: rhoopr <>
## Summary
* **What is the goal of this PR?**
* Increase the allowed link length for footnotes
* **What changes are included?**
* Un-magic-numbers parts of the footnote parser
* Increases max href length
## Additional Context
* Additional RAM usage was not noticable to me, worst case 16 * 128 * 2
= 4KB instead of previously 16 * 88 * 2 ~ 2.8KB, see #1031
* Motivation: My book navigated me to the start of the footnote chapter,
which required manual navigating for every footnote due to ungodly file
name choices which pushed the required href length to 72, which caused
truncating, which caused Crosspoint to not find the anchor (Sacred and
Terrible Air, available via reddit)
---
### 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**_
Switch KOReader sync progress mapping from chapter matching to
XPath-based mapping.
- resolves KOReader positions using real XHTML ancestry paths
- supports paragraph-based upload mapping with text offsets
where needed
- passes the current paragraph index into sync so uploads map
back to KOReader more accurately
No HTTP client changes are included. No reader-state or resume-flow
changes are included.
---------
Co-authored-by: jpirnay <jens@pirnay.com>
## Summary
**What is the goal of this PR?**
Added `destroyXmlParser()` helper to replace the repeated 4-line parser
cleanup block (stop, clear callbacks, free, null) that was copyied
across 6 XML parser files.
---
### 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
Previouls where ALL whitespace (and square brackes) removed from the
footnote link text, however some link texts are multiworded, like "`turn
to 252`" which were truncated into "`turnto252`", (an example from the
first book "Flight from the Dark" of the Lone Wolf book series by Joe
Dever, see [link](https://www.projectaon.org/en/Main/FlightFromTheDark))
* This change will only remove whitespaces from the beginning and end of
the string
so "` [ 12 ] `" will become "`12`" just like before, and "` turn to 252
`" will become "`turn to 252`".
---
### AI Usage
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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.)
`DESTRUCTOR_CLOSES_FILE=1` is set in platformio.ini, which makes SdFat's
FsBaseFile destructor call close() automatically when a file goes out of
scope.
Three categories of file close calls remain untouched:
1. Close before Storage.remove() on the same path: ScreenshotUtil.cpp
closes the file before deleting it on write error. The remove might fail
if the file is still open.
2. Close before reopening the same variable: Epub.cpp writes a temp
NCX/nav file, closes it, then reopens it for reading. The
RecentBooksStore.cpp close before saveToFile() is the same pattern, it
rewrites the same file.
3. Close on member variables: BookMetadataCache.cpp (bookFile,
spineFile, tocFile), Section.cpp (file), XtcParser.cpp (m_file),
ZipFile.cpp (file). These persist beyond any single function scope, so
the destructor timing doesn't match the intended close point.
---
### AI Usage
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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
* **What is the goal of this PR?** Slightly increase the OOM limit when
loading epubs
* **What changes are included?** Switched vectors for parsing epubs to
deques, allowing use of more memory
## Additional Context
* Increases loadable epub size from 2000+ chapter/ToC entries loadable
to 5000+ chapter/ToC entries
* #1574, but without the complicated stuff
---
### AI Usage
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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**_
### Testing
| Commit | Book | Time |
|----------|------|-------|
| 83cd96bc2f | 1000.epub | ~30 sec |
| 83cd96bc2f | 5000.epub | crash |
| PR | 1000.epub | ~29 sec |
| PR | 5000.epub | ~2 min 20 sec |
=> No actual loading time regressions
[tested_epubs.zip](https://github.com/user-attachments/files/26645243/tested_epubs.zip)
## Summary
Improves text antialiasing quality on the Xteink X3 (SSD1677) display to
bring it closer to X4 rendering quality. Addresses white lines through
letter strokes and ghosting artifacts during page turns and screen
transitions.
## Changes
### Display Driver (open-x4-sdk)
- Dedicated X3 grayscale LUTs with tuned VDL drive strengths for dark
gray (2 time units) and light gray (3 time units), with active GND hold
on non-gray transitions to prevent floating source crosstalk
- Tight scan timing: TP2/TP3 reduced to 1 (total gate-on 7 units vs 17),
minimizing parasitic charge leakage that caused white lines through
letter strokes
- Fast diff BB reinforcement: Added mild VDH reinforcing pulse to
lut_x3_bb_full so black pixels are actively driven during differential
refreshes, clearing gray residue/ghosting
- displayGrayBuffer() updated to use the dedicated gray LUT bank instead
of full refresh LUTs for X3
### Rendering Pipeline
- Re-enabled light gray rendering for X3 text and images, now safe with
dedicated gray LUTs providing proper 4-level gray
- Removed isLightGrayRestricted() gating that was limiting X3 to 3-level
gray
- Runtime display dimensions in DirectPixelWriter and ScreenshotUtil,
replaced hardcoded constants with runtime getters to support X3 792x528
resolution
### Note
The open-x4-sdk submodule references a commit on
juicecultus/community-sdk. A corresponding PR to
open-x4-epaper/community-sdk should be merged first so the submodule ref
resolves on upstream.
## Testing
Tested on physical X3 hardware. White lines through letters
significantly reduced, in-book ghosting improved via BB reinforcement,
antialiasing visually closer to X4 quality.
## AI Disclosure
Yes, AI was used to assist with the development of these changes.
---------
Replace hardcoded DISPLAY_WIDTH, DISPLAY_HEIGHT, and DISPLAY_WIDTH_BYTES
constants with runtime values from display object to support multiple
device models (X3 and X4) with different screen dimensions.
## Summary
**What is the goal of this PR?**
Replace verbose constructor initializer lists with in-class default
member initializers in JpegContext and PngContext
---
### 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
EPUBs that use ISO 639-2 three-letter language codes in their
`dc:language` metadata (e.g. `<dc:language>eng</dc:language>`) got no
hyphenation. The hyphenator registry only matched ISO 639-1 two-letter
codes (`"en"`, `"fr"`, etc.), so `"eng"` produced a null hyphenator and
every word in the book was treated as unhyphenatable.
Added a normalization step in `hyphenatorForLanguage` that maps ISO
639-2 codes (both bibliographic and terminological variants) to their
two-letter equivalents before the registry lookup.
Discovered via *Project Hail Mary* (Random House), which uses
`<dc:language>eng</dc:language>`.
---
### 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
Adds Xteink X3 hardware support to CrossPoint Reader. The X3 uses the
same SSD1677 e-ink controller as the X4 but with a different panel
(792x528 vs 800x480), different button layout, and an I2C fuel gauge
(BQ27220) instead of ADC-based battery reading.
All X3-specific behavior is gated by runtime device detection — X4
behavior is unchanged.
Depends on community-sdk X3 support: open-x4-epaper/community-sdk#19
(merged).
## Changes
### HAL Layer
**HalGPIO** (`lib/hal/HalGPIO.cpp/.h`)
- I2C-based device fingerprinting at boot: probes for BQ27220 fuel
gauge, DS3231 RTC, and QMI8658 IMU to distinguish X3 from X4
- Detection result cached in NVS for fast subsequent boots
- Exposes `deviceIsX3()` / `deviceIsX4()` helpers used throughout the
codebase
- X3 button mapping (7 GPIOs vs X4's layout)
- USB connection detection and wake classification for X3
**HalDisplay** (`lib/hal/HalDisplay.cpp/.h`)
- Calls `einkDisplay.setDisplayX3()` before init when X3 is detected
- Requests display resync after power button / flash wake events
- Runtime display dimension accessors (`getDisplayWidth()`,
`getDisplayHeight()`, `getBufferSize()`)
- Exposed as global `display` instance for use by image converters
**HalPowerManager** (`lib/hal/HalPowerManager.cpp/.h`)
- X3 battery reading via I2C fuel gauge (BQ27220 at 0x55, SOC register)
- X3 power button uses GPIO hold for deep sleep
### Display & Rendering
**GfxRenderer** (`lib/GfxRenderer/GfxRenderer.cpp/.h`)
- Buffer size and display dimensions are now runtime values (not
compile-time constants) to support both panel sizes
- X3 anti-aliasing tuning: only the darker grayscale level is applied to
avoid washed-out text on the X3 panel. X4 retains both levels via
`deviceIsX4()` gate
**Image Converters** (`lib/JpegToBmpConverter`, `lib/PngToBmpConverter`)
- Cover image prescale target uses runtime display dimensions from HAL
instead of hardcoded 800x480
### UI Themes
**BaseTheme / LyraTheme** (`src/components/themes/`)
- X3 button position mapping for the different physical layout
- Adjusted UI element positioning for 792x528 viewport
### Boot & Init
**main.cpp**
- X3 hardware detection logging
- Adjusted init sequence for X3 (no `HalSystem::begin()` dependency on
X3 path)
**HomeActivity**
- Uses runtime `renderer.getBufferSize()` instead of static
`GfxRenderer::getBufferSize()`
FYI I did not add support for the gyro page turner. That can be it's own
PR.
## Summary
Replace per-pixel getRenderMode() + rotateCoordinates() + bounds checks
with a DirectPixelWriter struct that pre-computes orientation and render
mode state once per row. Use bitwise ops instead of division/modulo for
cache pixel packing. Skip PNG cache allocation when buffer exceeds 48KB
(framebuffer size) since PNG decode is fast enough that caching provides
minimal benefit, and the large buffer competes with the 44KB PNG decoder
for heap.
## Additional Context
Measured improvements on ESP32-C3 @ 160MHz:
- JPEG decode: 5-7% faster (1:1 scale)
- PNG decode: 15-20% faster (1:1 scale)
- Cache renders: 3-6% faster across both formats
- Eliminates "Failed to allocate cache buffer" errors for large PNGs
---
### 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
- Add CSS `display: none` support to the EPUB rendering pipeline (fixes
#1431)
- Parse `display` property in stylesheets and inline styles, with full
cascade resolution (element, class, element.class, inline)
- Skip hidden elements and all their descendants in
`ChapterHtmlSlimParser`
- Separate display:none check for `<img>` tags (image code path is
independent of the general element handler)
- Flush pending text blocks before placing images to fix layout ordering
(text preceding an image now correctly renders above it)
- Bump CSS cache version to 4 to invalidate stale caches
- Add test EPUB (`test_display_none.epub`) covering class selectors,
element selectors, combined selectors, inline styles, nested hidden
content, hidden images, style priority/override, and realistic use cases
## Summary
* **What is the goal of this PR?** Fixing / extending the hyphenation
logic to deal with words containing an apostophe as raised in #1186
* **What changes are included?**
## 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**_ (as the
user provided a thorough analysis that I followed)
## 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
**What is the goal of this PR?**
### Problem
Inter-word gap widths were computed as two separately-snapped integers:
```cpp
gap = getSpaceWidth(fontId, style); // fp4::toPixel(spaceAdvance)
gap += getSpaceKernAdjust(fontId, leftCp, rightCp, style); // fp4::toPixel(kern1 + kern2)
```
Because `fp4::toPixel(a) + fp4::toPixel(b)` can differ from
`fp4::toPixel(a + b)` by +/-1 pixel when the fractional parts straddle a
rounding boundary, each inter-word space could be one pixel wider or
narrower than the correct value. This affected line-break width
decisions and word-position accumulation across the whole paragraph
layout pipeline.
### Fix
Replaces `getSpaceKernAdjust()` with `getSpaceAdvance(fontId, leftCp,
rightCp, style)`, which combines the space glyph advance and both
flanking kern values (`kern(leftCp, ' ')` + `kern(' ', rightCp)`) into a
single fixed-point sum before the snap:
```cpp
return fp4::toPixel(spaceAdvanceFP + kern(leftCp, ' ') + kern(' ', rightCp));
```
This is the same single-snap pattern already used by `getTextAdvanceX`
for word widths.
### Changes
- **`GfxRenderer`**: Replaces `getSpaceKernAdjust()` with
`getSpaceAdvance()`. `getSpaceWidth()` is retained for the
single-space-word case in `measureWordWidth` where no adjacent-word kern
context is available.
- **`ParsedText`**: All four call sites (`computeLineBreaks`,
`computeHyphenatedLineBreaks`, and both loops in `extractLine`) updated
to use `getSpaceAdvance()`. The now-redundant `spaceWidth`
pre-computation and parameter are removed from all three internal layout
functions.
---
### 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 to analyze for
correctness**_
## Summary
Fixes a crash (load access fault) when opening EPUB chapters whose first
text block exceeds 750 words.
## Changes
* **Crash fix (`addLineToPage`)**: Added a null guard for `currentPage`.
If `makePages()` hasn't run yet (which can happen when the first block
triggers the "text block too long" split path), the page is now created
on demand.
* **Layout fix (`characterData`)**: The early-split path previously used
`viewportWidth`, ignoring CSS margins and padding. It now computes
`effectiveWidth` using `totalHorizontalInset()`, consistent with
`makePages()`.
## Additional Context
* Crash signature: `MCAUSE=0x5` (load access fault), `A0=0x0` (`Page*`
null), `MTVAL=0x4 / 0x8` (offsets into `Page::elements`).
* Confirmed in two user reports reported in #1328
* Tested on PR #1357 (not on `master`).
---
### 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: 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?**
Avoid building cache path strings twice, once to check existence of the
file and a second time to delete the file.
---
### 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
* **What is the goal of this PR?** Fixing two independent CSS rendering
bugs combined to make hanging-indent list styles
(e.g. margin-left:3em; text-indent:-1em) render incorrectly:
* **What changes are included?**
1. Negative text-indent was silently ignored
Three guards in ParsedText.cpp (computeLineBreaks,
computeHyphenatedLineBreaks,
extractLine) conditioned firstLineIndent on blockStyle.textIndent > 0,
so any
negative value collapsed to zero. Additionally, wordXpos was uint16_t,
which
cannot represent negative offsets — a cast of e.g. −18 would wrap to
65518 and
render the word far off-screen.
2. extraParagraphSpacing suppressed hanging indents
Even after removing the > 0 guard, the existing !extraParagraphSpacing
condition
would still suppress all text-indent when that setting is on (its
default). Positive
text-indent is a decorative paragraph indent that the user can
reasonably replace with
vertical spacing — negative text-indent is structural (it positions the
list marker)
and must always apply.
3. em unit was calibrated against line height, not font size
emSize was computed as getLineHeight() * lineCompression (the full line
advance).
CSS em units are defined relative to the font-size, which corresponds to
the
ascender height — not the line height. Using line height makes every
em-based
margin/indent ~20–30% wider than a browser would render it, and is
especially
noticeable for CSS that uses font-size: small (which we do not
implement).
## Additional Context
Test case
```
.lsl1 { margin-left: 3em; text-indent: -1em; }
<div class="lsl1">• First list item that wraps across lines</div>
<div class="lsl1">• Short item</div>
```
Before: all lines of all items started at 3 em from the left edge
(indent ignored).
After: the bullet marker hangs at 2 em; continuation lines align at 3
em.
<img width="240" alt="before"
src="https://github.com/user-attachments/assets/9dcbf3e0-fcd9-4af8-b451-a90ba4d2fb75"
/>
<img width="240" alt="after"
src="https://github.com/user-attachments/assets/1ffdcf56-a180-4267-9590-c60d7ac44707"
/>
---
### 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
Replaces the picojpeg library with bitbank2/JPEGDEC for JPEG decoding in
the EPUB image pipeline. JPEGDEC provides built-in coarse scaling (1/2,
1/4, 1/8), 8-bit grayscale output, and streaming block-based decoding
via callbacks.
Includes a pre-build patch script for two JPEGDEC changes affecting
progressive JPEG support and EIGHT_BIT_GRAYSCALE mode.
Closes#912
## Additional Context
# Example progressive jpeg
<img
src="https://github.com/user-attachments/assets/e63bb4f8-f862-4aa0-a01f-d1ef43a4b27a"
width="400" height="800" />
Good performance increase from JPEGDEC over picojpeg cc @bitbank2 thanks
## Baseline JPEG Decode Performance: picojpeg vs JPEGDEC (float in
callback) vs JPEGDEC (fixed-point in callback)
Tested with `test_jpeg_images.epub` on device (ESP32-C3), first decode
(no cache).
| Image | Source | Output | picojpeg | JPEGDEC float | JPEGDEC
fixed-point | vs picojpeg | vs float |
|-------|--------|--------|----------|---------------|---------------------|-------------|----------|
| jpeg_format.jpg | 350x250 | 350x250 | 313 ms | 256 ms | **104 ms** |
**3.0x** | **2.5x** |
| grayscale_test.jpg | 400x600 | 400x600 | 768 ms | 661 ms | **246 ms**
| **3.1x** | **2.7x** |
| gradient_test.jpg | 400x500 | 400x500 | 707 ms | 597 ms | **247 ms** |
**2.9x** | **2.4x** |
| centering_test.jpg | 350x400 | 350x400 | 502 ms | 412 ms | **169 ms**
| **3.0x** | **2.4x** |
| scaling_test.jpg | 1200x1500 | 464x580 | 5487 ms | 1114 ms | **668
ms** | **8.2x** | **1.7x** |
| wide_scaling_test.jpg | 1807x736 | 464x188 | 4237 ms | 642 ms | **497
ms** | **8.5x** | **1.3x** |
| cache_test_1.jpg | 400x300 | 400x300 | 422 ms | 348 ms | **141 ms** |
**3.0x** | **2.5x** |
| cache_test_2.jpg | 400x300 | 400x300 | 424 ms | 349 ms | **142 ms** |
**3.0x** | **2.5x** |
### Summary
- **1:1 scale (fixed-point vs float)**: ~2.5x faster — eliminating
software float on the FPU-less ESP32-C3 is the dominant win
- **1:1 scale (fixed-point vs picojpeg)**: ~3.0x faster overall
- **Downscaled images (vs picojpeg)**: 8-9x faster — JPEGDEC's coarse
scaling + fixed-point draw callback
- **Downscaled images (fixed-point vs float)**: 1.3-1.7x — less dramatic
since JPEG library decode dominates over the draw callback for fewer
output pixels
- The fixed-point optimization alone (vs float JPEGDEC) saved **~60% of
render time** on 1:1 images, confirming that software float emulation
was the primary bottleneck in the draw callback
- See thread for discussions on quality of progressive images,
https://github.com/crosspoint-reader/crosspoint-reader/pull/1136#issuecomment-3952952315
- and the conclusion
https://github.com/crosspoint-reader/crosspoint-reader/pull/1136#issuecomment-3959379386
- Proposal to improve quality added at
https://github.com/crosspoint-reader/crosspoint-reader/discussions/1179
---
### 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 >**_
---------
Co-authored-by: Dave Allie <dave@daveallie.com>
## Summary
**What is the goal of this PR?** Replace the linear scan of
`lookupHtmlEntity` with a simple binary search to improve lookup
performance.
**What changes are included?**
`lib/Epub/Epub/Entities/htmlEntities.cpp`:
- Sorted the `ENTITY_LOOKUP` array.
- Added a compile-time assertion to guarantee the array remains sorted.
- Rewrote `lookupHtmlEntity` to use a binary search.
## Additional Context
Benchmarked on my x64 laptop (probably will be different on RISC-V)
```
=== Benchmark (53 entities x 10000 iterations) ===
Version Total time Avg per lookup
----------------------------------------------
linear 236.97 ms total 447.11 ns/lookup
binary search 22.09 ms total 41.68 ns/lookup
=== Summary ===
Binary search is 10.73x faster than linear scan.
```
This is a simplified alternative to #1180, focused on keeping the
implementation clean, and maintainable.
### AI Usage
Did you use AI tools to help write this code? _**< NO >**_
---------
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>
