Add support for reading the dst pixel value in an effect. Use in a new effect for the kDarken xfer mode.
The current implementation is to always make a copy of the entire dst before the draw.
It will only succeed if the RT is also a texture.
Obviously, there is lots of room for improvement.
Review URL: https://codereview.chromium.org/13314002
git-svn-id: http://skia.googlecode.com/svn/trunk@8449 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/gl/GrGLProgramDesc.h b/src/gpu/gl/GrGLProgramDesc.h
index 135d46c..b1660d8 100644
--- a/src/gpu/gl/GrGLProgramDesc.h
+++ b/src/gpu/gl/GrGLProgramDesc.h
@@ -10,6 +10,7 @@
#include "GrGLEffect.h"
#include "GrDrawState.h"
+#include "GrGLShaderBuilder.h"
class GrGpuGL;
@@ -18,9 +19,10 @@
#define GR_GL_EXPERIMENTAL_GS GR_DEBUG
-/** This class describes a program to generate. It also serves as a program cache key. The only
- thing GL-specific about this is the generation of GrGLEffect::EffectKeys. With some refactoring
- it could be made backend-neutral. */
+/** This class describes a program to generate. It also serves as a program cache key. Very little
+ of this is GL-specific. There is the generation of GrGLEffect::EffectKeys and the dst-read part
+ of the key set by GrGLShaderBuilder. If the interfaces that set those portions were abstracted
+ to be API-neutral then so could this class. */
class GrGLProgramDesc {
public:
GrGLProgramDesc() {
@@ -48,6 +50,7 @@
GrBlendCoeff srcCoeff,
GrBlendCoeff dstCoeff,
const GrGpuGL* gpu,
+ const GrDeviceCoordTexture* dstCopy,
GrGLProgramDesc* outDesc);
private:
@@ -86,6 +89,10 @@
#if GR_GL_EXPERIMENTAL_GS
bool fExperimentalGS;
#endif
+ GrGLShaderBuilder::DstReadKey fDstRead; // set by GrGLShaderBuilder if there
+ // are effects that must read the dst.
+ // Otherwise, 0.
+
uint8_t fColorInput; // casts to enum ColorInput
uint8_t fCoverageInput; // casts to enum ColorInput
uint8_t fDualSrcOutput; // casts to enum DualSrcOutput
@@ -98,8 +105,10 @@
int8_t fCoverageAttributeIndex;
int8_t fLocalCoordsAttributeIndex;
- // GrGLProgram reads the private fields to generate code.
+ // GrGLProgram and GrGLShaderBuilder read the private fields to generate code. TODO: Move all
+ // code generation to GrGLShaderBuilder (and maybe add getters rather than friending).
friend class GrGLProgram;
+ friend class GrGLShaderBuilder;
};
#endif