Implement Porter Duff XP with a blend table

include/gpu/effects/GrPorterDuffXferProcessor.h

Index: include/gpu/effects/GrPorterDuffXferProcessor.h
diff --git a/include/gpu/effects/GrPorterDuffXferProcessor.h b/include/gpu/effects/GrPorterDuffXferProcessor.h
index 481b373c10ac6a8170d43469b60a3b768f77b55c..8e8d72dcc209a0c9e1fcfd6bc7c4f7692b80af94 100644
--- a/include/gpu/effects/GrPorterDuffXferProcessor.h
+++ b/include/gpu/effects/GrPorterDuffXferProcessor.h
@@ -24,7 +24,7 @@ public:
                             GrXPFactory::InvariantOutput*) const override;
 
 private:
-    GrPorterDuffXPFactory(GrBlendCoeff src, GrBlendCoeff dst); 
+    GrPorterDuffXPFactory(SkXfermode::Mode);
 
     GrXferProcessor* onCreateXferProcessor(const GrCaps& caps,
                                            const GrProcOptInfo& colorPOI,
@@ -37,15 +37,18 @@ private:
 
     bool onIsEqual(const GrXPFactory& xpfBase) const override {
         const GrPorterDuffXPFactory& xpf = xpfBase.cast<GrPorterDuffXPFactory>();
-        return (fSrcCoeff == xpf.fSrcCoeff && fDstCoeff == xpf.fDstCoeff);
+        return fXfermode == xpf.fXfermode;
     }
 
     GR_DECLARE_XP_FACTORY_TEST;
 
-    GrBlendCoeff fSrcCoeff;
-    GrBlendCoeff fDstCoeff;
+    SkXfermode::Mode fXfermode;
 
     typedef GrXPFactory INHERITED;
+
+public:
+    static int TestGetXPOutputPrimay(const GrXferProcessor*);
+    static int TestGetXPOutputSecondary(const GrXferProcessor*);

[Chris Dalton, 2015/05/19 21:47:13]

Not sure if there is a "more preferred" way to get specifics to the unit
tests...

[egdaniel, 2015/05/20 18:59:42]

I'm not really a fan of making these public getters. Our general approach is to
friend something in the unit test thus these can be made private

[Chris Dalton, 2015/05/21 10:00:48]

Done.

 };
 
 #endif