Implement color filter as GrGLEffect

src/gpu/GrDrawState.h

Index: src/gpu/GrDrawState.h
diff --git a/src/gpu/GrDrawState.h b/src/gpu/GrDrawState.h
index 6440790c10b1d611e651ea786f97a4b0a008d79e..6dcb2dc487ce08b6fe96acfb1d018f753c1238f3 100644
--- a/src/gpu/GrDrawState.h
+++ b/src/gpu/GrDrawState.h
@@ -266,18 +266,6 @@ public:
     }
 
     /**
-     * Add a color filter that can be represented by a color and a mode. Applied
-     * after color-computing effect stages.
-     */
-    void setColorFilter(GrColor c, SkXfermode::Mode mode) {
-        fCommon.fColorFilterColor = c;
-        fCommon.fColorFilterMode = mode;
-    }
-
-    GrColor getColorFilterColor() const { return fCommon.fColorFilterColor; }
-    SkXfermode::Mode getColorFilterMode() const { return fCommon.fColorFilterMode; }
-
-    /**
      * Constructor sets the color to be 'color' which is undone by the destructor.
      */
     class AutoColorRestore : public ::SkNoncopyable {
@@ -360,6 +348,9 @@ public:
 
     const GrEffectRef* addColorEffect(const GrEffectRef* effect, int attr0 = -1, int attr1 = -1) {
         SkASSERT(NULL != effect);
+        if (!(*effect)->willUseInputColor()) {

[bsalomon, 2013/10/02 16:37:59]

I don't think this is safe because of AutoRestoreEffects(). We either need to
address that, or just keep the effects around and ignore them when we turn this
draw state into a program (skip effects before an effect that ignores its
input).

Also, I think we would want similar logic in addCoverageEffect().

[Kimmo Kinnunen, 2013/10/04 06:21:18]

Done. Not sure the new naming is the best possible, though.

+            fColorStages.reset();
+        }
         SkNEW_APPEND_TO_TARRAY(&fColorStages, GrEffectStage, (effect, attr0, attr1));
         return effect;
     }
@@ -915,8 +906,6 @@ private:
         fCommon.fFlagBits = 0x0;
         fCommon.fStencilSettings.setDisabled();
         fCommon.fCoverage = 0xffffffff;
-        fCommon.fColorFilterMode = SkXfermode::kDst_Mode;
-        fCommon.fColorFilterColor = 0x0;
         fCommon.fDrawFace = kBoth_DrawFace;
     }
 
@@ -933,8 +922,6 @@ private:
         int                   fVACount;
         GrStencilSettings     fStencilSettings;
         GrColor               fCoverage;
-        SkXfermode::Mode      fColorFilterMode;
-        GrColor               fColorFilterColor;
         DrawFace              fDrawFace;
 
         // This is simply a different representation of info in fVertexAttribs and thus does
@@ -952,8 +939,6 @@ private:
                           !memcmp(fVAPtr, other.fVAPtr, fVACount * sizeof(GrVertexAttrib)) &&
                           fStencilSettings == other.fStencilSettings &&
                           fCoverage == other.fCoverage &&
-                          fColorFilterMode == other.fColorFilterMode &&
-                          fColorFilterColor == other.fColorFilterColor &&
                           fDrawFace == other.fDrawFace;
             SkASSERT(!result || 0 == memcmp(fFixedFunctionVertexAttribIndices,
                                             other.fFixedFunctionVertexAttribIndices,