Files
crosspoint-reader-mod/lib/GfxRenderer/GfxRenderer.cpp
Adrian Wilkins-Caruana 47aa0dda76 perf: Reduce overall flash usage by 30.7% by compressing built-in fonts (#831)
## 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>
2026-02-19 20:30:15 +11:00

1058 lines
35 KiB
C++

#include "GfxRenderer.h"
#include <Logging.h>
#include <Utf8.h>
const uint8_t* GfxRenderer::getGlyphBitmap(const EpdFontData* fontData, const EpdGlyph* glyph) const {
if (fontData->groups != nullptr) {
if (!fontDecompressor) {
LOG_ERR("GFX", "Compressed font but no FontDecompressor set");
return nullptr;
}
uint16_t glyphIndex = static_cast<uint16_t>(glyph - fontData->glyph);
return fontDecompressor->getBitmap(fontData, glyph, glyphIndex);
}
return &fontData->bitmap[glyph->dataOffset];
}
void GfxRenderer::begin() {
frameBuffer = display.getFrameBuffer();
if (!frameBuffer) {
LOG_ERR("GFX", "!! No framebuffer");
assert(false);
}
}
void GfxRenderer::insertFont(const int fontId, EpdFontFamily font) { fontMap.insert({fontId, font}); }
// Translate logical (x,y) coordinates to physical panel coordinates based on current orientation
// This should always be inlined for better performance
static inline void rotateCoordinates(const GfxRenderer::Orientation orientation, const int x, const int y, int* phyX,
int* phyY) {
switch (orientation) {
case GfxRenderer::Portrait: {
// Logical portrait (480x800) → panel (800x480)
// Rotation: 90 degrees clockwise
*phyX = y;
*phyY = HalDisplay::DISPLAY_HEIGHT - 1 - x;
break;
}
case GfxRenderer::LandscapeClockwise: {
// Logical landscape (800x480) rotated 180 degrees (swap top/bottom and left/right)
*phyX = HalDisplay::DISPLAY_WIDTH - 1 - x;
*phyY = HalDisplay::DISPLAY_HEIGHT - 1 - y;
break;
}
case GfxRenderer::PortraitInverted: {
// Logical portrait (480x800) → panel (800x480)
// Rotation: 90 degrees counter-clockwise
*phyX = HalDisplay::DISPLAY_WIDTH - 1 - y;
*phyY = x;
break;
}
case GfxRenderer::LandscapeCounterClockwise: {
// Logical landscape (800x480) aligned with panel orientation
*phyX = x;
*phyY = y;
break;
}
}
}
// IMPORTANT: This function is in critical rendering path and is called for every pixel. Please keep it as simple and
// efficient as possible.
void GfxRenderer::drawPixel(const int x, const int y, const bool state) const {
int phyX = 0;
int phyY = 0;
// Note: this call should be inlined for better performance
rotateCoordinates(orientation, x, y, &phyX, &phyY);
// Bounds checking against physical panel dimensions
if (phyX < 0 || phyX >= HalDisplay::DISPLAY_WIDTH || phyY < 0 || phyY >= HalDisplay::DISPLAY_HEIGHT) {
LOG_ERR("GFX", "!! Outside range (%d, %d) -> (%d, %d)", x, y, phyX, phyY);
return;
}
// Calculate byte position and bit position
const uint16_t byteIndex = phyY * HalDisplay::DISPLAY_WIDTH_BYTES + (phyX / 8);
const uint8_t bitPosition = 7 - (phyX % 8); // MSB first
if (state) {
frameBuffer[byteIndex] &= ~(1 << bitPosition); // Clear bit
} else {
frameBuffer[byteIndex] |= 1 << bitPosition; // Set bit
}
}
int GfxRenderer::getTextWidth(const int fontId, const char* text, const EpdFontFamily::Style style) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
int w = 0, h = 0;
fontIt->second.getTextDimensions(text, &w, &h, style);
return w;
}
void GfxRenderer::drawCenteredText(const int fontId, const int y, const char* text, const bool black,
const EpdFontFamily::Style style) const {
const int x = (getScreenWidth() - getTextWidth(fontId, text, style)) / 2;
drawText(fontId, x, y, text, black, style);
}
void GfxRenderer::drawText(const int fontId, const int x, const int y, const char* text, const bool black,
const EpdFontFamily::Style style) const {
const int yPos = y + getFontAscenderSize(fontId);
int xpos = x;
// cannot draw a NULL / empty string
if (text == nullptr || *text == '\0') {
return;
}
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return;
}
const auto& font = fontIt->second;
// no printable characters
if (!font.hasPrintableChars(text, style)) {
return;
}
uint32_t cp;
while ((cp = utf8NextCodepoint(reinterpret_cast<const uint8_t**>(&text)))) {
renderChar(font, cp, &xpos, &yPos, black, style);
}
}
void GfxRenderer::drawLine(int x1, int y1, int x2, int y2, const bool state) const {
if (x1 == x2) {
if (y2 < y1) {
std::swap(y1, y2);
}
for (int y = y1; y <= y2; y++) {
drawPixel(x1, y, state);
}
} else if (y1 == y2) {
if (x2 < x1) {
std::swap(x1, x2);
}
for (int x = x1; x <= x2; x++) {
drawPixel(x, y1, state);
}
} else {
// TODO: Implement
LOG_ERR("GFX", "Line drawing not supported");
}
}
void GfxRenderer::drawLine(int x1, int y1, int x2, int y2, const int lineWidth, const bool state) const {
for (int i = 0; i < lineWidth; i++) {
drawLine(x1, y1 + i, x2, y2 + i, state);
}
}
void GfxRenderer::drawRect(const int x, const int y, const int width, const int height, const bool state) const {
drawLine(x, y, x + width - 1, y, state);
drawLine(x + width - 1, y, x + width - 1, y + height - 1, state);
drawLine(x + width - 1, y + height - 1, x, y + height - 1, state);
drawLine(x, y, x, y + height - 1, state);
}
// Border is inside the rectangle
void GfxRenderer::drawRect(const int x, const int y, const int width, const int height, const int lineWidth,
const bool state) const {
for (int i = 0; i < lineWidth; i++) {
drawLine(x + i, y + i, x + width - i, y + i, state);
drawLine(x + width - i, y + i, x + width - i, y + height - i, state);
drawLine(x + width - i, y + height - i, x + i, y + height - i, state);
drawLine(x + i, y + height - i, x + i, y + i, state);
}
}
void GfxRenderer::drawArc(const int maxRadius, const int cx, const int cy, const int xDir, const int yDir,
const int lineWidth, const bool state) const {
const int stroke = std::min(lineWidth, maxRadius);
const int innerRadius = std::max(maxRadius - stroke, 0);
const int outerRadiusSq = maxRadius * maxRadius;
const int innerRadiusSq = innerRadius * innerRadius;
for (int dy = 0; dy <= maxRadius; ++dy) {
for (int dx = 0; dx <= maxRadius; ++dx) {
const int distSq = dx * dx + dy * dy;
if (distSq > outerRadiusSq || distSq < innerRadiusSq) {
continue;
}
const int px = cx + xDir * dx;
const int py = cy + yDir * dy;
drawPixel(px, py, state);
}
}
};
// Border is inside the rectangle, rounded corners
void GfxRenderer::drawRoundedRect(const int x, const int y, const int width, const int height, const int lineWidth,
const int cornerRadius, bool state) const {
drawRoundedRect(x, y, width, height, lineWidth, cornerRadius, true, true, true, true, state);
}
// Border is inside the rectangle, rounded corners
void GfxRenderer::drawRoundedRect(const int x, const int y, const int width, const int height, const int lineWidth,
const int cornerRadius, bool roundTopLeft, bool roundTopRight, bool roundBottomLeft,
bool roundBottomRight, bool state) const {
if (lineWidth <= 0 || width <= 0 || height <= 0) {
return;
}
const int maxRadius = std::min({cornerRadius, width / 2, height / 2});
if (maxRadius <= 0) {
drawRect(x, y, width, height, lineWidth, state);
return;
}
const int stroke = std::min(lineWidth, maxRadius);
const int right = x + width - 1;
const int bottom = y + height - 1;
const int horizontalWidth = width - 2 * maxRadius;
if (horizontalWidth > 0) {
if (roundTopLeft || roundTopRight) {
fillRect(x + maxRadius, y, horizontalWidth, stroke, state);
}
if (roundBottomLeft || roundBottomRight) {
fillRect(x + maxRadius, bottom - stroke + 1, horizontalWidth, stroke, state);
}
}
const int verticalHeight = height - 2 * maxRadius;
if (verticalHeight > 0) {
if (roundTopLeft || roundBottomLeft) {
fillRect(x, y + maxRadius, stroke, verticalHeight, state);
}
if (roundTopRight || roundBottomRight) {
fillRect(right - stroke + 1, y + maxRadius, stroke, verticalHeight, state);
}
}
if (roundTopLeft) {
drawArc(maxRadius, x + maxRadius, y + maxRadius, -1, -1, lineWidth, state);
}
if (roundTopRight) {
drawArc(maxRadius, right - maxRadius, y + maxRadius, 1, -1, lineWidth, state);
}
if (roundBottomRight) {
drawArc(maxRadius, right - maxRadius, bottom - maxRadius, 1, 1, lineWidth, state);
}
if (roundBottomLeft) {
drawArc(maxRadius, x + maxRadius, bottom - maxRadius, -1, 1, lineWidth, state);
}
}
void GfxRenderer::fillRect(const int x, const int y, const int width, const int height, const bool state) const {
for (int fillY = y; fillY < y + height; fillY++) {
drawLine(x, fillY, x + width - 1, fillY, state);
}
}
// NOTE: Those are in critical path, and need to be templated to avoid runtime checks for every pixel.
// Any branching must be done outside the loops to avoid performance degradation.
template <>
void GfxRenderer::drawPixelDither<Color::Clear>(const int x, const int y) const {
// Do nothing
}
template <>
void GfxRenderer::drawPixelDither<Color::Black>(const int x, const int y) const {
drawPixel(x, y, true);
}
template <>
void GfxRenderer::drawPixelDither<Color::White>(const int x, const int y) const {
drawPixel(x, y, false);
}
template <>
void GfxRenderer::drawPixelDither<Color::LightGray>(const int x, const int y) const {
drawPixel(x, y, x % 2 == 0 && y % 2 == 0);
}
template <>
void GfxRenderer::drawPixelDither<Color::DarkGray>(const int x, const int y) const {
drawPixel(x, y, (x + y) % 2 == 0); // TODO: maybe find a better pattern?
}
void GfxRenderer::fillRectDither(const int x, const int y, const int width, const int height, Color color) const {
if (color == Color::Clear) {
} else if (color == Color::Black) {
fillRect(x, y, width, height, true);
} else if (color == Color::White) {
fillRect(x, y, width, height, false);
} else if (color == Color::LightGray) {
for (int fillY = y; fillY < y + height; fillY++) {
for (int fillX = x; fillX < x + width; fillX++) {
drawPixelDither<Color::LightGray>(fillX, fillY);
}
}
} else if (color == Color::DarkGray) {
for (int fillY = y; fillY < y + height; fillY++) {
for (int fillX = x; fillX < x + width; fillX++) {
drawPixelDither<Color::DarkGray>(fillX, fillY);
}
}
}
}
template <Color color>
void GfxRenderer::fillArc(const int maxRadius, const int cx, const int cy, const int xDir, const int yDir) const {
const int radiusSq = maxRadius * maxRadius;
for (int dy = 0; dy <= maxRadius; ++dy) {
for (int dx = 0; dx <= maxRadius; ++dx) {
const int distSq = dx * dx + dy * dy;
const int px = cx + xDir * dx;
const int py = cy + yDir * dy;
if (distSq <= radiusSq) {
drawPixelDither<color>(px, py);
}
}
}
}
void GfxRenderer::fillRoundedRect(const int x, const int y, const int width, const int height, const int cornerRadius,
const Color color) const {
fillRoundedRect(x, y, width, height, cornerRadius, true, true, true, true, color);
}
void GfxRenderer::fillRoundedRect(const int x, const int y, const int width, const int height, const int cornerRadius,
bool roundTopLeft, bool roundTopRight, bool roundBottomLeft, bool roundBottomRight,
const Color color) const {
if (width <= 0 || height <= 0) {
return;
}
const int maxRadius = std::min({cornerRadius, width / 2, height / 2});
if (maxRadius <= 0) {
fillRectDither(x, y, width, height, color);
return;
}
const int horizontalWidth = width - 2 * maxRadius;
if (horizontalWidth > 0) {
fillRectDither(x + maxRadius + 1, y, horizontalWidth - 2, height, color);
}
const int verticalHeight = height - 2 * maxRadius - 2;
if (verticalHeight > 0) {
fillRectDither(x, y + maxRadius + 1, maxRadius + 1, verticalHeight, color);
fillRectDither(x + width - maxRadius - 1, y + maxRadius + 1, maxRadius + 1, verticalHeight, color);
}
auto fillArcTemplated = [this](int maxRadius, int cx, int cy, int xDir, int yDir, Color color) {
switch (color) {
case Color::Clear:
break;
case Color::Black:
fillArc<Color::Black>(maxRadius, cx, cy, xDir, yDir);
break;
case Color::White:
fillArc<Color::White>(maxRadius, cx, cy, xDir, yDir);
break;
case Color::LightGray:
fillArc<Color::LightGray>(maxRadius, cx, cy, xDir, yDir);
break;
case Color::DarkGray:
fillArc<Color::DarkGray>(maxRadius, cx, cy, xDir, yDir);
break;
}
};
if (roundTopLeft) {
fillArcTemplated(maxRadius, x + maxRadius, y + maxRadius, -1, -1, color);
} else {
fillRectDither(x, y, maxRadius + 1, maxRadius + 1, color);
}
if (roundTopRight) {
fillArcTemplated(maxRadius, x + width - maxRadius - 1, y + maxRadius, 1, -1, color);
} else {
fillRectDither(x + width - maxRadius - 1, y, maxRadius + 1, maxRadius + 1, color);
}
if (roundBottomRight) {
fillArcTemplated(maxRadius, x + width - maxRadius - 1, y + height - maxRadius - 1, 1, 1, color);
} else {
fillRectDither(x + width - maxRadius - 1, y + height - maxRadius - 1, maxRadius + 1, maxRadius + 1, color);
}
if (roundBottomLeft) {
fillArcTemplated(maxRadius, x + maxRadius, y + height - maxRadius - 1, -1, 1, color);
} else {
fillRectDither(x, y + height - maxRadius - 1, maxRadius + 1, maxRadius + 1, color);
}
}
void GfxRenderer::drawImage(const uint8_t bitmap[], const int x, const int y, const int width, const int height) const {
int rotatedX = 0;
int rotatedY = 0;
rotateCoordinates(orientation, x, y, &rotatedX, &rotatedY);
// Rotate origin corner
switch (orientation) {
case Portrait:
rotatedY = rotatedY - height;
break;
case PortraitInverted:
rotatedX = rotatedX - width;
break;
case LandscapeClockwise:
rotatedY = rotatedY - height;
rotatedX = rotatedX - width;
break;
case LandscapeCounterClockwise:
break;
}
// TODO: Rotate bits
display.drawImage(bitmap, rotatedX, rotatedY, width, height);
}
void GfxRenderer::drawIcon(const uint8_t bitmap[], const int x, const int y, const int width, const int height) const {
display.drawImage(bitmap, y, getScreenWidth() - width - x, height, width);
}
void GfxRenderer::drawBitmap(const Bitmap& bitmap, const int x, const int y, const int maxWidth, const int maxHeight,
const float cropX, const float cropY) const {
// For 1-bit bitmaps, use optimized 1-bit rendering path (no crop support for 1-bit)
if (bitmap.is1Bit() && cropX == 0.0f && cropY == 0.0f) {
drawBitmap1Bit(bitmap, x, y, maxWidth, maxHeight);
return;
}
float scale = 1.0f;
bool isScaled = false;
int cropPixX = std::floor(bitmap.getWidth() * cropX / 2.0f);
int cropPixY = std::floor(bitmap.getHeight() * cropY / 2.0f);
LOG_DBG("GFX", "Cropping %dx%d by %dx%d pix, is %s", bitmap.getWidth(), bitmap.getHeight(), cropPixX, cropPixY,
bitmap.isTopDown() ? "top-down" : "bottom-up");
if (maxWidth > 0 && (1.0f - cropX) * bitmap.getWidth() > maxWidth) {
scale = static_cast<float>(maxWidth) / static_cast<float>((1.0f - cropX) * bitmap.getWidth());
isScaled = true;
}
if (maxHeight > 0 && (1.0f - cropY) * bitmap.getHeight() > maxHeight) {
scale = std::min(scale, static_cast<float>(maxHeight) / static_cast<float>((1.0f - cropY) * bitmap.getHeight()));
isScaled = true;
}
LOG_DBG("GFX", "Scaling by %f - %s", scale, isScaled ? "scaled" : "not scaled");
// Calculate output row size (2 bits per pixel, packed into bytes)
// IMPORTANT: Use int, not uint8_t, to avoid overflow for images > 1020 pixels wide
const int outputRowSize = (bitmap.getWidth() + 3) / 4;
auto* outputRow = static_cast<uint8_t*>(malloc(outputRowSize));
auto* rowBytes = static_cast<uint8_t*>(malloc(bitmap.getRowBytes()));
if (!outputRow || !rowBytes) {
LOG_ERR("GFX", "!! Failed to allocate BMP row buffers");
free(outputRow);
free(rowBytes);
return;
}
for (int bmpY = 0; bmpY < (bitmap.getHeight() - cropPixY); bmpY++) {
// The BMP's (0, 0) is the bottom-left corner (if the height is positive, top-left if negative).
// Screen's (0, 0) is the top-left corner.
int screenY = -cropPixY + (bitmap.isTopDown() ? bmpY : bitmap.getHeight() - 1 - bmpY);
if (isScaled) {
screenY = std::floor(screenY * scale);
}
screenY += y; // the offset should not be scaled
if (screenY >= getScreenHeight()) {
break;
}
if (bitmap.readNextRow(outputRow, rowBytes) != BmpReaderError::Ok) {
LOG_ERR("GFX", "Failed to read row %d from bitmap", bmpY);
free(outputRow);
free(rowBytes);
return;
}
if (screenY < 0) {
continue;
}
if (bmpY < cropPixY) {
// Skip the row if it's outside the crop area
continue;
}
for (int bmpX = cropPixX; bmpX < bitmap.getWidth() - cropPixX; bmpX++) {
int screenX = bmpX - cropPixX;
if (isScaled) {
screenX = std::floor(screenX * scale);
}
screenX += x; // the offset should not be scaled
if (screenX >= getScreenWidth()) {
break;
}
if (screenX < 0) {
continue;
}
const uint8_t val = outputRow[bmpX / 4] >> (6 - ((bmpX * 2) % 8)) & 0x3;
if (renderMode == BW && val < 3) {
drawPixel(screenX, screenY);
} else if (renderMode == GRAYSCALE_MSB && (val == 1 || val == 2)) {
drawPixel(screenX, screenY, false);
} else if (renderMode == GRAYSCALE_LSB && val == 1) {
drawPixel(screenX, screenY, false);
}
}
}
free(outputRow);
free(rowBytes);
}
void GfxRenderer::drawBitmap1Bit(const Bitmap& bitmap, const int x, const int y, const int maxWidth,
const int maxHeight) const {
float scale = 1.0f;
bool isScaled = false;
if (maxWidth > 0 && bitmap.getWidth() > maxWidth) {
scale = static_cast<float>(maxWidth) / static_cast<float>(bitmap.getWidth());
isScaled = true;
}
if (maxHeight > 0 && bitmap.getHeight() > maxHeight) {
scale = std::min(scale, static_cast<float>(maxHeight) / static_cast<float>(bitmap.getHeight()));
isScaled = true;
}
// For 1-bit BMP, output is still 2-bit packed (for consistency with readNextRow)
const int outputRowSize = (bitmap.getWidth() + 3) / 4;
auto* outputRow = static_cast<uint8_t*>(malloc(outputRowSize));
auto* rowBytes = static_cast<uint8_t*>(malloc(bitmap.getRowBytes()));
if (!outputRow || !rowBytes) {
LOG_ERR("GFX", "!! Failed to allocate 1-bit BMP row buffers");
free(outputRow);
free(rowBytes);
return;
}
for (int bmpY = 0; bmpY < bitmap.getHeight(); bmpY++) {
// Read rows sequentially using readNextRow
if (bitmap.readNextRow(outputRow, rowBytes) != BmpReaderError::Ok) {
LOG_ERR("GFX", "Failed to read row %d from 1-bit bitmap", bmpY);
free(outputRow);
free(rowBytes);
return;
}
// Calculate screen Y based on whether BMP is top-down or bottom-up
const int bmpYOffset = bitmap.isTopDown() ? bmpY : bitmap.getHeight() - 1 - bmpY;
int screenY = y + (isScaled ? static_cast<int>(std::floor(bmpYOffset * scale)) : bmpYOffset);
if (screenY >= getScreenHeight()) {
continue; // Continue reading to keep row counter in sync
}
if (screenY < 0) {
continue;
}
for (int bmpX = 0; bmpX < bitmap.getWidth(); bmpX++) {
int screenX = x + (isScaled ? static_cast<int>(std::floor(bmpX * scale)) : bmpX);
if (screenX >= getScreenWidth()) {
break;
}
if (screenX < 0) {
continue;
}
// Get 2-bit value (result of readNextRow quantization)
const uint8_t val = outputRow[bmpX / 4] >> (6 - ((bmpX * 2) % 8)) & 0x3;
// For 1-bit source: 0 or 1 -> map to black (0,1,2) or white (3)
// val < 3 means black pixel (draw it)
if (val < 3) {
drawPixel(screenX, screenY, true);
}
// White pixels (val == 3) are not drawn (leave background)
}
}
free(outputRow);
free(rowBytes);
}
void GfxRenderer::fillPolygon(const int* xPoints, const int* yPoints, int numPoints, bool state) const {
if (numPoints < 3) return;
// Find bounding box
int minY = yPoints[0], maxY = yPoints[0];
for (int i = 1; i < numPoints; i++) {
if (yPoints[i] < minY) minY = yPoints[i];
if (yPoints[i] > maxY) maxY = yPoints[i];
}
// Clip to screen
if (minY < 0) minY = 0;
if (maxY >= getScreenHeight()) maxY = getScreenHeight() - 1;
// Allocate node buffer for scanline algorithm
auto* nodeX = static_cast<int*>(malloc(numPoints * sizeof(int)));
if (!nodeX) {
LOG_ERR("GFX", "!! Failed to allocate polygon node buffer");
return;
}
// Scanline fill algorithm
for (int scanY = minY; scanY <= maxY; scanY++) {
int nodes = 0;
// Find all intersection points with edges
int j = numPoints - 1;
for (int i = 0; i < numPoints; i++) {
if ((yPoints[i] < scanY && yPoints[j] >= scanY) || (yPoints[j] < scanY && yPoints[i] >= scanY)) {
// Calculate X intersection using fixed-point to avoid float
int dy = yPoints[j] - yPoints[i];
if (dy != 0) {
nodeX[nodes++] = xPoints[i] + (scanY - yPoints[i]) * (xPoints[j] - xPoints[i]) / dy;
}
}
j = i;
}
// Sort nodes by X (simple bubble sort, numPoints is small)
for (int i = 0; i < nodes - 1; i++) {
for (int k = i + 1; k < nodes; k++) {
if (nodeX[i] > nodeX[k]) {
int temp = nodeX[i];
nodeX[i] = nodeX[k];
nodeX[k] = temp;
}
}
}
// Fill between pairs of nodes
for (int i = 0; i < nodes - 1; i += 2) {
int startX = nodeX[i];
int endX = nodeX[i + 1];
// Clip to screen
if (startX < 0) startX = 0;
if (endX >= getScreenWidth()) endX = getScreenWidth() - 1;
// Draw horizontal line
for (int x = startX; x <= endX; x++) {
drawPixel(x, scanY, state);
}
}
}
free(nodeX);
}
// For performance measurement (using static to allow "const" methods)
static unsigned long start_ms = 0;
void GfxRenderer::clearScreen(const uint8_t color) const {
start_ms = millis();
display.clearScreen(color);
}
void GfxRenderer::invertScreen() const {
for (int i = 0; i < HalDisplay::BUFFER_SIZE; i++) {
frameBuffer[i] = ~frameBuffer[i];
}
}
void GfxRenderer::displayBuffer(const HalDisplay::RefreshMode refreshMode) const {
auto elapsed = millis() - start_ms;
LOG_DBG("GFX", "Time = %lu ms from clearScreen to displayBuffer", elapsed);
display.displayBuffer(refreshMode, fadingFix);
}
std::string GfxRenderer::truncatedText(const int fontId, const char* text, const int maxWidth,
const EpdFontFamily::Style style) const {
if (!text || maxWidth <= 0) return "";
std::string item = text;
const char* ellipsis = "...";
int textWidth = getTextWidth(fontId, item.c_str(), style);
if (textWidth <= maxWidth) {
// Text fits, return as is
return item;
}
while (!item.empty() && getTextWidth(fontId, (item + ellipsis).c_str(), style) >= maxWidth) {
utf8RemoveLastChar(item);
}
return item.empty() ? ellipsis : item + ellipsis;
}
// Note: Internal driver treats screen in command orientation; this library exposes a logical orientation
int GfxRenderer::getScreenWidth() const {
switch (orientation) {
case Portrait:
case PortraitInverted:
// 480px wide in portrait logical coordinates
return HalDisplay::DISPLAY_HEIGHT;
case LandscapeClockwise:
case LandscapeCounterClockwise:
// 800px wide in landscape logical coordinates
return HalDisplay::DISPLAY_WIDTH;
}
return HalDisplay::DISPLAY_HEIGHT;
}
int GfxRenderer::getScreenHeight() const {
switch (orientation) {
case Portrait:
case PortraitInverted:
// 800px tall in portrait logical coordinates
return HalDisplay::DISPLAY_WIDTH;
case LandscapeClockwise:
case LandscapeCounterClockwise:
// 480px tall in landscape logical coordinates
return HalDisplay::DISPLAY_HEIGHT;
}
return HalDisplay::DISPLAY_WIDTH;
}
int GfxRenderer::getSpaceWidth(const int fontId) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
return fontIt->second.getGlyph(' ', EpdFontFamily::REGULAR)->advanceX;
}
int GfxRenderer::getTextAdvanceX(const int fontId, const char* text) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
uint32_t cp;
int width = 0;
const auto& font = fontIt->second;
while ((cp = utf8NextCodepoint(reinterpret_cast<const uint8_t**>(&text)))) {
width += font.getGlyph(cp, EpdFontFamily::REGULAR)->advanceX;
}
return width;
}
int GfxRenderer::getFontAscenderSize(const int fontId) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
return fontIt->second.getData(EpdFontFamily::REGULAR)->ascender;
}
int GfxRenderer::getLineHeight(const int fontId) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
return fontIt->second.getData(EpdFontFamily::REGULAR)->advanceY;
}
int GfxRenderer::getTextHeight(const int fontId) const {
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return 0;
}
return fontIt->second.getData(EpdFontFamily::REGULAR)->ascender;
}
void GfxRenderer::drawTextRotated90CW(const int fontId, const int x, const int y, const char* text, const bool black,
const EpdFontFamily::Style style) const {
// Cannot draw a NULL / empty string
if (text == nullptr || *text == '\0') {
return;
}
const auto fontIt = fontMap.find(fontId);
if (fontIt == fontMap.end()) {
LOG_ERR("GFX", "Font %d not found", fontId);
return;
}
const auto& font = fontIt->second;
// No printable characters
if (!font.hasPrintableChars(text, style)) {
return;
}
// For 90° clockwise rotation:
// Original (glyphX, glyphY) -> Rotated (glyphY, -glyphX)
// Text reads from bottom to top
int yPos = y; // Current Y position (decreases as we draw characters)
uint32_t cp;
while ((cp = utf8NextCodepoint(reinterpret_cast<const uint8_t**>(&text)))) {
const EpdGlyph* glyph = font.getGlyph(cp, style);
if (!glyph) {
glyph = font.getGlyph(REPLACEMENT_GLYPH, style);
}
if (!glyph) {
continue;
}
const EpdFontData* fontData = font.getData(style);
const int is2Bit = fontData->is2Bit;
const uint8_t width = glyph->width;
const uint8_t height = glyph->height;
const int left = glyph->left;
const int top = glyph->top;
const uint8_t* bitmap = getGlyphBitmap(fontData, glyph);
if (bitmap != nullptr) {
for (int glyphY = 0; glyphY < height; glyphY++) {
for (int glyphX = 0; glyphX < width; glyphX++) {
const int pixelPosition = glyphY * width + glyphX;
// 90° clockwise rotation transformation:
// screenX = x + (ascender - top + glyphY)
// screenY = yPos - (left + glyphX)
const int screenX = x + (fontData->ascender - top + glyphY);
const int screenY = yPos - left - glyphX;
if (is2Bit) {
const uint8_t byte = bitmap[pixelPosition / 4];
const uint8_t bit_index = (3 - pixelPosition % 4) * 2;
const uint8_t bmpVal = 3 - (byte >> bit_index) & 0x3;
if (renderMode == BW && bmpVal < 3) {
drawPixel(screenX, screenY, black);
} else if (renderMode == GRAYSCALE_MSB && (bmpVal == 1 || bmpVal == 2)) {
drawPixel(screenX, screenY, false);
} else if (renderMode == GRAYSCALE_LSB && bmpVal == 1) {
drawPixel(screenX, screenY, false);
}
} else {
const uint8_t byte = bitmap[pixelPosition / 8];
const uint8_t bit_index = 7 - (pixelPosition % 8);
if ((byte >> bit_index) & 1) {
drawPixel(screenX, screenY, black);
}
}
}
}
}
// Move to next character position (going up, so decrease Y)
yPos -= glyph->advanceX;
}
}
uint8_t* GfxRenderer::getFrameBuffer() const { return frameBuffer; }
size_t GfxRenderer::getBufferSize() { return HalDisplay::BUFFER_SIZE; }
// unused
// void GfxRenderer::grayscaleRevert() const { display.grayscaleRevert(); }
void GfxRenderer::copyGrayscaleLsbBuffers() const { display.copyGrayscaleLsbBuffers(frameBuffer); }
void GfxRenderer::copyGrayscaleMsbBuffers() const { display.copyGrayscaleMsbBuffers(frameBuffer); }
void GfxRenderer::displayGrayBuffer() const { display.displayGrayBuffer(fadingFix); }
void GfxRenderer::freeBwBufferChunks() {
for (auto& bwBufferChunk : bwBufferChunks) {
if (bwBufferChunk) {
free(bwBufferChunk);
bwBufferChunk = nullptr;
}
}
}
/**
* This should be called before grayscale buffers are populated.
* A `restoreBwBuffer` call should always follow the grayscale render if this method was called.
* Uses chunked allocation to avoid needing 48KB of contiguous memory.
* Returns true if buffer was stored successfully, false if allocation failed.
*/
bool GfxRenderer::storeBwBuffer() {
// Allocate and copy each chunk
for (size_t i = 0; i < BW_BUFFER_NUM_CHUNKS; i++) {
// Check if any chunks are already allocated
if (bwBufferChunks[i]) {
LOG_ERR("GFX", "!! BW buffer chunk %zu already stored - this is likely a bug, freeing chunk", i);
free(bwBufferChunks[i]);
bwBufferChunks[i] = nullptr;
}
const size_t offset = i * BW_BUFFER_CHUNK_SIZE;
bwBufferChunks[i] = static_cast<uint8_t*>(malloc(BW_BUFFER_CHUNK_SIZE));
if (!bwBufferChunks[i]) {
LOG_ERR("GFX", "!! Failed to allocate BW buffer chunk %zu (%zu bytes)", i, BW_BUFFER_CHUNK_SIZE);
// Free previously allocated chunks
freeBwBufferChunks();
return false;
}
memcpy(bwBufferChunks[i], frameBuffer + offset, BW_BUFFER_CHUNK_SIZE);
}
LOG_DBG("GFX", "Stored BW buffer in %zu chunks (%zu bytes each)", BW_BUFFER_NUM_CHUNKS, BW_BUFFER_CHUNK_SIZE);
return true;
}
/**
* This can only be called if `storeBwBuffer` was called prior to the grayscale render.
* It should be called to restore the BW buffer state after grayscale rendering is complete.
* Uses chunked restoration to match chunked storage.
*/
void GfxRenderer::restoreBwBuffer() {
// Check if any all chunks are allocated
bool missingChunks = false;
for (const auto& bwBufferChunk : bwBufferChunks) {
if (!bwBufferChunk) {
missingChunks = true;
break;
}
}
if (missingChunks) {
freeBwBufferChunks();
return;
}
for (size_t i = 0; i < BW_BUFFER_NUM_CHUNKS; i++) {
// Check if chunk is missing
if (!bwBufferChunks[i]) {
LOG_ERR("GFX", "!! BW buffer chunks not stored - this is likely a bug");
freeBwBufferChunks();
return;
}
const size_t offset = i * BW_BUFFER_CHUNK_SIZE;
memcpy(frameBuffer + offset, bwBufferChunks[i], BW_BUFFER_CHUNK_SIZE);
}
display.cleanupGrayscaleBuffers(frameBuffer);
freeBwBufferChunks();
LOG_DBG("GFX", "Restored and freed BW buffer chunks");
}
/**
* Cleanup grayscale buffers using the current frame buffer.
* Use this when BW buffer was re-rendered instead of stored/restored.
*/
void GfxRenderer::cleanupGrayscaleWithFrameBuffer() const {
if (frameBuffer) {
display.cleanupGrayscaleBuffers(frameBuffer);
}
}
void GfxRenderer::renderChar(const EpdFontFamily& fontFamily, const uint32_t cp, int* x, const int* y,
const bool pixelState, const EpdFontFamily::Style style) const {
const EpdGlyph* glyph = fontFamily.getGlyph(cp, style);
if (!glyph) {
glyph = fontFamily.getGlyph(REPLACEMENT_GLYPH, style);
}
// no glyph?
if (!glyph) {
LOG_ERR("GFX", "No glyph for codepoint %d", cp);
return;
}
const EpdFontData* fontData = fontFamily.getData(style);
const int is2Bit = fontData->is2Bit;
const uint8_t width = glyph->width;
const uint8_t height = glyph->height;
const int left = glyph->left;
const uint8_t* bitmap = getGlyphBitmap(fontData, glyph);
if (bitmap != nullptr) {
for (int glyphY = 0; glyphY < height; glyphY++) {
const int screenY = *y - glyph->top + glyphY;
for (int glyphX = 0; glyphX < width; glyphX++) {
const int pixelPosition = glyphY * width + glyphX;
const int screenX = *x + left + glyphX;
if (is2Bit) {
const uint8_t byte = bitmap[pixelPosition / 4];
const uint8_t bit_index = (3 - pixelPosition % 4) * 2;
// the direct bit from the font is 0 -> white, 1 -> light gray, 2 -> dark gray, 3 -> black
// we swap this to better match the way images and screen think about colors:
// 0 -> black, 1 -> dark grey, 2 -> light grey, 3 -> white
const uint8_t bmpVal = 3 - (byte >> bit_index) & 0x3;
if (renderMode == BW && bmpVal < 3) {
// Black (also paints over the grays in BW mode)
drawPixel(screenX, screenY, pixelState);
} else if (renderMode == GRAYSCALE_MSB && (bmpVal == 1 || bmpVal == 2)) {
// Light gray (also mark the MSB if it's going to be a dark gray too)
// We have to flag pixels in reverse for the gray buffers, as 0 leave alone, 1 update
drawPixel(screenX, screenY, false);
} else if (renderMode == GRAYSCALE_LSB && bmpVal == 1) {
// Dark gray
drawPixel(screenX, screenY, false);
}
} else {
const uint8_t byte = bitmap[pixelPosition / 8];
const uint8_t bit_index = 7 - (pixelPosition % 8);
if ((byte >> bit_index) & 1) {
drawPixel(screenX, screenY, pixelState);
}
}
}
}
}
*x += glyph->advanceX;
}
void GfxRenderer::getOrientedViewableTRBL(int* outTop, int* outRight, int* outBottom, int* outLeft) const {
switch (orientation) {
case Portrait:
*outTop = VIEWABLE_MARGIN_TOP;
*outRight = VIEWABLE_MARGIN_RIGHT;
*outBottom = VIEWABLE_MARGIN_BOTTOM;
*outLeft = VIEWABLE_MARGIN_LEFT;
break;
case LandscapeClockwise:
*outTop = VIEWABLE_MARGIN_LEFT;
*outRight = VIEWABLE_MARGIN_TOP;
*outBottom = VIEWABLE_MARGIN_RIGHT;
*outLeft = VIEWABLE_MARGIN_BOTTOM;
break;
case PortraitInverted:
*outTop = VIEWABLE_MARGIN_BOTTOM;
*outRight = VIEWABLE_MARGIN_LEFT;
*outBottom = VIEWABLE_MARGIN_TOP;
*outLeft = VIEWABLE_MARGIN_RIGHT;
break;
case LandscapeCounterClockwise:
*outTop = VIEWABLE_MARGIN_RIGHT;
*outRight = VIEWABLE_MARGIN_BOTTOM;
*outBottom = VIEWABLE_MARGIN_LEFT;
*outLeft = VIEWABLE_MARGIN_TOP;
break;
}
}