## 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
Fix https://github.com/crosspoint-reader/crosspoint-reader/issues/1137
Introducing `HalFile`, a thin wrapper around `FsFile` that uses a global
mutex to protect file operations.
To test this PR, place the code below somewhere in the code base (I
placed it in `onGoToRecentBooks`)
```cpp
static auto testTask = [](void* param) {
for (int i = 0; i < 10; i++) {
String json = Storage.readFile("/.crosspoint/settings.json");
LOG_DBG("TEST_TASK", "Read settings.json, bytes read: %u", json.length());
}
vTaskDelete(nullptr);
};
xTaskCreate(testTask, "test0", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test1", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test2", 8192, nullptr, 1, nullptr);
xTaskCreate(testTask, "test3", 8192, nullptr, 1, nullptr);
delay(1000);
```
It will reliably lead to crash on `master`, but will function correctly
with this PR.
A macro renaming trick is used to avoid changing too many downstream
code 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**, only to
help with tedious copy-paste tasks
---------
Co-authored-by: Zach Nelson <zach@zdnelson.com>
## Summary
* Remove miniz and move completely to uzlib
* Move uzlib interfacing to InflateReader to better modularise inflation
code
---
### 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, Claude helped with
the extraction and refactor
## Summary
**What is the goal of this PR?**
* Implement feature request
[#954](https://github.com/crosspoint-reader/crosspoint-reader/issues/954)
* Ensure cover images are scaled up to match the dimensions of the
screen, as well as scaled down
**What changes are included?**
* Naïve implementation for scaling up the source image
## Additional Context
If you find the extra comments to be excessive I can pare them back.
Edit: Fixed title
---
### 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
- EPUB books with PNG cover images now display covers on the home screen
instead of blank rectangles
- Adds `PngToBmpConverter` library mirroring the existing
`JpegToBmpConverter` pattern
- Uses miniz (already in the project) for streaming zlib decompression
of PNG IDAT data
- Supports all PNG color types (Grayscale, RGB, RGBA, Palette,
Gray+Alpha)
- Optimized for ESP32-C3: batch grayscale conversion, 2KB read buffer,
same area-averaging scaling and Atkinson dithering as the JPEG path
## Changes
- **New:** `lib/PngToBmpConverter/PngToBmpConverter.h` — Public API
matching JpegToBmpConverter's interface
- **New:** `lib/PngToBmpConverter/PngToBmpConverter.cpp` — Streaming PNG
decoder + BMP converter
- **Modified:** `lib/Epub/Epub.cpp` — Added `.png` handling in
`generateCoverBmp()` and `generateThumbBmp()`
## Test plan
- [x] Tested with EPUB files using PNG covers — covers appear correctly
on home screen
- [ ] Verify with various PNG color types (most stock EPUBs use 8-bit
RGB)
- [ ] Confirm no regressions with JPEG cover EPUBs
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
**New Features**
- Added PNG format support for EPUB cover and thumbnail images. PNG
files are automatically processed and cached alongside existing
supported formats. This enhancement enables users to leverage PNG cover
artwork when generating EPUB files, improving workflow flexibility and
compatibility with common image sources.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
---------
Co-authored-by: Nik Outchcunis <outchy@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Dave Allie <dave@daveallie.com>
