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

Special case for zero-byte prewarm

Browse Source
This commit is contained in:
jpirnay
2026-05-11 22:57:15 +02:00
parent b96be90a0c
commit fddc81ec0a
1 changed files with 10 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/EpdFont/FontDecompressor.cpp
+10
View File
@@ -259,6 +259,10 @@ int FontDecompressor::prewarmCache(const EpdFontData* fontData, const char* utf8
int32_t glyphIdx = findGlyphIndex(fontData, cp); int32_t glyphIdx = findGlyphIndex(fontData, cp);
if (glyphIdx < 0) continue; if (glyphIdx < 0) continue;
const EpdGlyph& glyph = fontData->glyph[glyphIdx];
// Whitespace/empty glyphs have no bitmap payload and do not need prewarm storage.
if (glyph.dataLength == 0 || glyph.width == 0 || glyph.height == 0) continue;
// Deduplicate against already prewarmed slots // Deduplicate against already prewarmed slots
bool alreadyCached = false; bool alreadyCached = false;
for (uint8_t s = 0; s < pageSlotCount; s++) { for (uint8_t s = 0; s < pageSlotCount; s++) {
@@ -376,6 +380,12 @@ int FontDecompressor::prewarmCache(const EpdFontData* fontData, const char* utf8
stats.uniqueGroupsAccessed = groupCount; stats.uniqueGroupsAccessed = groupCount;
// Safety: if the collected glyph set has no bitmap payload, skip slot allocation.
if (totalBytes == 0) {
LOG_DBG("FDC", "Prewarm skipped: %u glyphs but 0 bitmap bytes", glyphCount);
return 0;
}
// Sort neededGroups by ascending group index so flash reads are sequential. // Sort neededGroups by ascending group index so flash reads are sequential.
// Uses insertion sort — groupCount is bounded at 128, typically <14 for Latin fonts. // Uses insertion sort — groupCount is bounded at 128, typically <14 for Latin fonts.
for (uint8_t i = 1; i < groupCount; i++) { for (uint8_t i = 1; i < groupCount; i++) {