eric/Crosspoint
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat: render grayscale epub images without text aa (#2393)

Browse Source
This commit is contained in:
Julia
2026-06-22 17:15:27 +03:00
committed by GitHub
parent 0ce874f8d4
commit d1abcc00a2
3 changed files with 51 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/Epub/Epub/Page.cpp
+20 -3
View File
@@ -6,6 +6,20 @@
#include <new>
namespace {
template <typename Predicate>
void renderFilteredPageElements(const std::vector<std::shared_ptr<PageElement>>& elements, GfxRenderer& renderer,
const int fontId, const int xOffset, const int yOffset, Predicate&& predicate) {
for (const auto& element : elements) {
if (predicate(*element)) {
element->render(renderer, fontId, xOffset, yOffset);
}
}
}
} // namespace
void PageLine::render(GfxRenderer& renderer, const int fontId, const int xOffset, const int yOffset) {
block->render(renderer, fontId, xPos + xOffset, yPos + yOffset);
}
@@ -93,9 +107,12 @@ std::unique_ptr<PageHorizontalRule> PageHorizontalRule::deserialize(HalFile& fil
}
void Page::render(GfxRenderer& renderer, const int fontId, const int xOffset, const int yOffset) const {
for (auto& element : elements) {
element->render(renderer, fontId, xOffset, yOffset);
}
renderFilteredPageElements(elements, renderer, fontId, xOffset, yOffset, [](const PageElement&) { return true; });
}
void Page::renderImages(GfxRenderer& renderer, const int fontId, const int xOffset, const int yOffset) const {
renderFilteredPageElements(elements, renderer, fontId, xOffset, yOffset,
[](const PageElement& element) { return element.getTag() == TAG_PageImage; });
}
bool Page::serialize(HalFile& file) const {
lib/Epub/Epub/Page.h
+1
View File
@@ -88,6 +88,7 @@ class Page {
}
void render(GfxRenderer& renderer, int fontId, int xOffset, int yOffset) const;
void renderImages(GfxRenderer& renderer, int fontId, int xOffset, int yOffset) const;
bool serialize(HalFile& file) const;
static std::unique_ptr<Page> deserialize(HalFile& file);
src/activities/reader/EpubReaderActivity.cpp
+30 -15
View File
@@ -976,22 +976,31 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
const int orientedMarginRight, const int orientedMarginBottom,
const int orientedMarginLeft) {
const auto t0 = millis();
const int fontId = SETTINGS.getReaderFontId();
// Font prewarm: scan pass accumulates text, then prewarm, then real render
auto* fcm = renderer.getFontCacheManager();
auto scope = fcm->createPrewarmScope();
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop); // scan pass
page->render(renderer, fontId, orientedMarginLeft, orientedMarginTop); // scan pass
scope.endScanAndPrewarm();
const auto tPrewarm = millis();
// Force special handling for pages with images when anti-aliasing is on
bool imagePageWithAA = page->hasImages() && SETTINGS.textAntiAliasing;
const bool pageHasImages = page->hasImages();
const bool needsTextGrayscale = SETTINGS.textAntiAliasing;
const bool needsAnyGrayscale = needsTextGrayscale || pageHasImages;
auto renderGrayscalePass = [&]() {
if (needsTextGrayscale) {
page->render(renderer, fontId, orientedMarginLeft, orientedMarginTop);
} else {
page->renderImages(renderer, fontId, orientedMarginLeft, orientedMarginTop);
}
};
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
page->render(renderer, fontId, orientedMarginLeft, orientedMarginTop);
renderStatusBar();
const auto tBwRender = millis();
if (imagePageWithAA) {
if (pageHasImages) {
// Double FAST_REFRESH with selective image blanking (pablohc's technique):
// HALF_REFRESH sets particles too firmly for the grayscale LUT to adjust.
// Instead, blank only the image area and do two fast refreshes.
@@ -1004,7 +1013,7 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
// Re-render page content to restore images into the blanked area
// Status bar is not re-rendered here to avoid reading stale dynamic values (e.g. battery %)
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
page->render(renderer, fontId, orientedMarginLeft, orientedMarginTop);
renderer.displayBuffer(HalDisplay::FAST_REFRESH);
} else {
renderer.displayBuffer(HalDisplay::HALF_REFRESH);
@@ -1028,7 +1037,7 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
// per plane, but renderCharImpl culls out-of-band glyphs before decode so the
// cost stays close to one render. Both text (drawPixel) and images
// (DirectPixelWriter) honor the active strip target.
if (SETTINGS.textAntiAliasing && renderer.supportsStripGrayscale()) {
if (needsAnyGrayscale && renderer.supportsStripGrayscale()) {
constexpr int STRIP_ROWS = 80;
const int gh = renderer.getDisplayHeight();
const int gwBytes = renderer.getDisplayWidthBytes();
@@ -1044,7 +1053,7 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
const int rows = (gh - y < STRIP_ROWS) ? (gh - y) : STRIP_ROWS;
renderer.beginStripTarget(scratch.get(), y, rows);
renderer.clearScreen(0x00);
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
renderGrayscalePass();
renderer.endStripTarget();
renderer.writeGrayscalePlaneStrip(true, scratch.get(), y, rows);
}
@@ -1056,7 +1065,7 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
const int rows = (gh - y < STRIP_ROWS) ? (gh - y) : STRIP_ROWS;
renderer.beginStripTarget(scratch.get(), y, rows);
renderer.clearScreen(0x00);
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
renderGrayscalePass();
renderer.endStripTarget();
renderer.writeGrayscalePlaneStrip(false, scratch.get(), y, rows);
}
@@ -1081,22 +1090,28 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
} else {
// Fallback path for a controller without strip support. grayscale rendering
// TODO: Only do this if font supports it
if (SETTINGS.textAntiAliasing) {
if (needsAnyGrayscale) {
// Save the BW frame before the grayscale passes overwrite it, restore
// after. Only needed when grayscale actually renders.
renderer.storeBwBuffer();
if (!renderer.storeBwBuffer()) {
LOG_ERR("ERS", "Failed to store BW buffer for grayscale render; skipping grayscale this page");
const auto tEnd = millis();
LOG_DBG("ERS", "Page render: prewarm=%lums bw_render=%lums display=%lums total=%lums", tPrewarm - t0,
tBwRender - tPrewarm, tDisplay - tBwRender, tEnd - t0);
return;
}
const auto tBwStore = millis();
renderer.clearScreen(0x00);
renderer.setRenderMode(GfxRenderer::GRAYSCALE_LSB);
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
renderGrayscalePass();
renderer.copyGrayscaleLsbBuffers();
const auto tGrayLsb = millis();
// Render and copy to MSB buffer
renderer.clearScreen(0x00);
renderer.setRenderMode(GfxRenderer::GRAYSCALE_MSB);
page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
renderGrayscalePass();
renderer.copyGrayscaleMsbBuffers();
const auto tGrayMsb = millis();
@@ -1114,8 +1129,8 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
tPrewarm - t0, tBwRender - tPrewarm, tDisplay - tBwRender, tBwStore - tDisplay, tGrayLsb - tBwStore,
tGrayMsb - tGrayLsb, tGrayDisplay - tGrayMsb, tBwRestore - tGrayDisplay, tEnd - t0);
} else {
// No anti-aliasing: BW frame already displayed above, no grayscale to
// render, so no save/restore.
// No text AA and no images: BW frame already displayed above, no grayscale
// to render, so no save/restore.
const auto tEnd = millis();
LOG_DBG("ERS", "Page render: prewarm=%lums bw_render=%lums display=%lums total=%lums", tPrewarm - t0,
tBwRender - tPrewarm, tDisplay - tBwRender, tEnd - t0);