Don't create a GXPFactory when blend is SrcOver
BUG=skia:
Review URL: https://codereview.chromium.org/1471053002
diff --git a/src/gpu/effects/GrPorterDuffXferProcessor.cpp b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
index 4245caa..2323c67 100644
--- a/src/gpu/effects/GrPorterDuffXferProcessor.cpp
+++ b/src/gpu/effects/GrPorterDuffXferProcessor.cpp
@@ -830,3 +830,65 @@
*outPrimary = blendFormula.fPrimaryOutputType;
*outSecondary = blendFormula.fSecondaryOutputType;
}
+
+
+////////////////////////////////////////////////////////////////////////////////////////////////
+// SrcOver Global functions
+////////////////////////////////////////////////////////////////////////////////////////////////
+
+GrXferProcessor* GrPorterDuffXPFactory::CreateSrcOverXferProcessor(
+ const GrCaps& caps,
+ const GrProcOptInfo& colorPOI,
+ const GrProcOptInfo& covPOI,
+ bool hasMixedSamples,
+ const GrXferProcessor::DstTexture* dstTexture) {
+ BlendFormula blendFormula;
+ if (covPOI.isFourChannelOutput()) {
+ if (kRGBA_GrColorComponentFlags == colorPOI.validFlags() &&
+ !caps.shaderCaps()->dualSourceBlendingSupport() &&
+ !caps.shaderCaps()->dstReadInShaderSupport()) {
+ // If we don't have dual source blending or in shader dst reads, we fall
+ // back to this trick for rendering SrcOver LCD text instead of doing a
+ // dst copy.
+ SkASSERT(!dstTexture || !dstTexture->texture());
+ return PDLCDXferProcessor::Create(SkXfermode::kSrcOver_Mode, colorPOI);
+ }
+ blendFormula = get_lcd_blend_formula(covPOI, SkXfermode::kSrcOver_Mode);
+ } else {
+ blendFormula = get_blend_formula(colorPOI, covPOI, hasMixedSamples,
+ SkXfermode::kSrcOver_Mode);
+ }
+
+ if (blendFormula.hasSecondaryOutput() && !caps.shaderCaps()->dualSourceBlendingSupport()) {
+ return new ShaderPDXferProcessor(dstTexture, hasMixedSamples, SkXfermode::kSrcOver_Mode);
+ }
+
+ SkASSERT(!dstTexture || !dstTexture->texture());
+ return new PorterDuffXferProcessor(blendFormula);
+}
+
+bool GrPorterDuffXPFactory::SrcOverWillNeedDstTexture(const GrCaps& caps,
+ const GrProcOptInfo& colorPOI,
+ const GrProcOptInfo& covPOI,
+ bool hasMixedSamples) {
+ if (caps.shaderCaps()->dstReadInShaderSupport() ||
+ caps.shaderCaps()->dualSourceBlendingSupport()) {
+ return false;
+ }
+
+ // When we have four channel coverage we always need to read the dst in order to correctly
+ // blend. The one exception is when we are using srcover mode and we know the input color
+ // into the XP.
+ if (covPOI.isFourChannelOutput()) {
+ if (kRGBA_GrColorComponentFlags == colorPOI.validFlags() &&
+ !caps.shaderCaps()->dstReadInShaderSupport()) {
+ return false;
+ }
+ return get_lcd_blend_formula(covPOI, SkXfermode::kSrcOver_Mode).hasSecondaryOutput();
+ }
+ // We fallback on the shader XP when the blend formula would use dual source blending but we
+ // don't have support for it.
+ return get_blend_formula(colorPOI, covPOI,
+ hasMixedSamples, SkXfermode::kSrcOver_Mode).hasSecondaryOutput();
+}
+