respect preferred config when png is index-based
git-svn-id: http://skia.googlecode.com/svn/trunk@261 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/images/SkImageDecoder_libpng.cpp b/src/images/SkImageDecoder_libpng.cpp
index 81e73ef..8f2652a 100644
--- a/src/images/SkImageDecoder_libpng.cpp
+++ b/src/images/SkImageDecoder_libpng.cpp
@@ -110,6 +110,12 @@
return reallyHasAlpha;
}
+static inline bool isDirectModel(SkBitmap::Config config) {
+ return config == SkBitmap::kARGB_8888_Config ||
+ config == SkBitmap::kARGB_4444_Config ||
+ config == SkBitmap::kRGB_565_Config;
+}
+
bool SkPNGImageDecoder::onDecode(SkStream* sk_stream, SkBitmap* decodedBitmap,
SkBitmap::Config prefConfig, Mode mode) {
// SkAutoTrace apr("SkPNGImageDecoder::onDecode");
@@ -292,7 +298,7 @@
// to |= PNG_COLOR_MASK_ALPHA, but all of its pixels are in fact opaque. We care, since we
// draw lots faster if we can flag the bitmap has being opaque
bool reallyHasAlpha = false;
-
+ bool upscaleFromPalette = false;
SkColorTable* colorTable = NULL;
if (color_type == PNG_COLOR_TYPE_PALETTE) {
@@ -346,11 +352,23 @@
*colorPtr = colorPtr[-1];
}
colorTable->unlockColors(true);
+
+ // see if we need to upscale to a direct-model
+ if (isDirectModel(prefConfig)) {
+ if (!reallyHasAlpha || SkBitmap::kRGB_565_Config != prefConfig) {
+ upscaleFromPalette = true;
+ config = prefConfig;
+ // need to re-call setConfig
+ decodedBitmap->setConfig(config, sampler.scaledWidth(),
+ sampler.scaledHeight(), 0);
+ }
+ }
}
SkAutoUnref aur(colorTable);
- if (!this->allocPixelRef(decodedBitmap, colorTable)) {
+ if (!this->allocPixelRef(decodedBitmap,
+ upscaleFromPalette ? NULL : colorTable)) {
return false;
}
@@ -392,7 +410,7 @@
SkScaledBitmapSampler::SrcConfig sc;
int srcBytesPerPixel = 4;
- if (SkBitmap::kIndex8_Config == config) {
+ if (colorTable != NULL) {
sc = SkScaledBitmapSampler::kIndex;
srcBytesPerPixel = 1;
} else if (hasAlpha) {
@@ -400,7 +418,13 @@
} else {
sc = SkScaledBitmapSampler::kRGBX;
}
- if (!sampler.begin(decodedBitmap, sc, doDither)) {
+
+ /* We have to pass the colortable explicitly, since we may have one
+ even if our decodedBitmap doesn't, due to the request that we
+ upscale png's palette to a direct model
+ */
+ SkAutoLockColors ctLock(colorTable);
+ if (!sampler.begin(decodedBitmap, sc, doDither, ctLock.colors())) {
return false;
}
const int height = decodedBitmap->height();