SF: Skip render-to-texture for color transforms
In cases where SurfaceFlinger is applying a color matrix (usually for
accessibility features), we previously would perform a render-to-
texture for the initial composition, and then apply the matrix during
a copy to the framebuffer. This changes that behavior to just apply the
matrix during composition without a render-to-texture pass.
This may result in a perceived change of the image in cases with alpha
blending, since the blending is performed at a different stage of the
pipeline and the system effectively performs non-linear blends.
However, neither this nor the prior render-to-texture pass is strictly
correct in that regard, and this approach is less error-prone and
likely faster.
Change-Id: I2110ff0374f61d76df7b087dde8a1ed98990440c
diff --git a/services/surfaceflinger/RenderEngine/RenderEngine.h b/services/surfaceflinger/RenderEngine/RenderEngine.h
index 8d7529c..31a961e 100644
--- a/services/surfaceflinger/RenderEngine/RenderEngine.h
+++ b/services/surfaceflinger/RenderEngine/RenderEngine.h
@@ -99,18 +99,16 @@
virtual void setupLayerBlackedOut() = 0;
virtual void setupFillWithColor(float r, float g, float b, float a) = 0;
+ virtual mat4 setupColorTransform(const mat4& /* colorTransform */) {
+ return mat4();
+ }
+
virtual void disableTexturing() = 0;
virtual void disableBlending() = 0;
// drawing
virtual void drawMesh(const Mesh& mesh) = 0;
- // grouping
- // creates a color-transform group, everything drawn in the group will be
- // transformed by the given color transform when endGroup() is called.
- virtual void beginGroup(const mat4& colorTransform) = 0;
- virtual void endGroup() = 0;
-
// queries
virtual size_t getMaxTextureSize() const = 0;
virtual size_t getMaxViewportDims() const = 0;