Fixed light gray text rendering

This commit is contained in:
Dave Allie 2025-12-16 02:16:35 +11:00
parent 6989035ef8
commit 449b3ca161
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GPG Key ID: F2FDDB3AD8D0276F
3 changed files with 23 additions and 15 deletions

View File

@ -207,14 +207,20 @@ void GfxRenderer::renderChar(const EpdFontFamily& fontFamily, const uint32_t cp,
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;
const uint8_t val = (byte >> bit_index) & 0x3;
if (fontRenderMode == BW && val > 0) {
if (renderMode == BW && bmpVal < 3) {
// Black (also paints over the grays in BW mode)
drawPixel(screenX, screenY, pixelState);
} else if (fontRenderMode == GRAYSCALE_MSB && val == 1) {
// TODO: Not sure how this anti-aliasing goes on black backgrounds
} 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 (fontRenderMode == GRAYSCALE_LSB && val == 2) {
} else if (renderMode == GRAYSCALE_LSB && bmpVal == 1) {
// Dark gray
drawPixel(screenX, screenY, false);
}
} else {

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@ -7,17 +7,17 @@
class GfxRenderer {
public:
enum FontRenderMode { BW, GRAYSCALE_LSB, GRAYSCALE_MSB };
enum RenderMode { BW, GRAYSCALE_LSB, GRAYSCALE_MSB };
private:
EInkDisplay& einkDisplay;
FontRenderMode fontRenderMode;
RenderMode renderMode;
std::map<int, EpdFontFamily> fontMap;
void renderChar(const EpdFontFamily& fontFamily, uint32_t cp, int* x, const int* y, bool pixelState,
EpdFontStyle style) const;
public:
explicit GfxRenderer(EInkDisplay& einkDisplay) : einkDisplay(einkDisplay), fontRenderMode(BW) {}
explicit GfxRenderer(EInkDisplay& einkDisplay) : einkDisplay(einkDisplay), renderMode(BW) {}
~GfxRenderer() = default;
// Setup
@ -41,15 +41,17 @@ class GfxRenderer {
int getTextWidth(int fontId, const char* text, EpdFontStyle style = REGULAR) const;
void drawCenteredText(int fontId, int y, const char* text, bool black = true, EpdFontStyle style = REGULAR) const;
void drawText(int fontId, int x, int y, const char* text, bool black = true, EpdFontStyle style = REGULAR) const;
void setFontRenderMode(const FontRenderMode mode) { this->fontRenderMode = mode; }
int getSpaceWidth(int fontId) const;
int getLineHeight(int fontId) const;
// Grayscale functions
void setRenderMode(const RenderMode mode) { this->renderMode = mode; }
void copyGrayscaleLsbBuffers() const;
void copyGrayscaleMsbBuffers() const;
void displayGrayBuffer() const;
// Low level functions
uint8_t* getFrameBuffer() const;
void swapBuffers() const;
void grayscaleRevert() const;
void copyGrayscaleLsbBuffers() const;
void copyGrayscaleMsbBuffers() const;
void displayGrayBuffer() const;
};

View File

@ -301,19 +301,19 @@ void EpubReaderScreen::renderContents(std::unique_ptr<Page> page) {
// TODO: Only do this if font supports it
{
renderer.clearScreen(0x00);
renderer.setFontRenderMode(GfxRenderer::GRAYSCALE_LSB);
renderer.setRenderMode(GfxRenderer::GRAYSCALE_LSB);
page->render(renderer, READER_FONT_ID);
renderer.copyGrayscaleLsbBuffers();
// Render and copy to MSB buffer
renderer.clearScreen(0x00);
renderer.setFontRenderMode(GfxRenderer::GRAYSCALE_MSB);
renderer.setRenderMode(GfxRenderer::GRAYSCALE_MSB);
page->render(renderer, READER_FONT_ID);
renderer.copyGrayscaleMsbBuffers();
// display grayscale part
renderer.displayGrayBuffer();
renderer.setFontRenderMode(GfxRenderer::BW);
renderer.setRenderMode(GfxRenderer::BW);
}
}