Create fragment processor for performing input color blend with child processor

The new FP is used to implement SkXM::Mode color filters and SkXM::Mode image filters. Also, these now support all advanced SkXM::Mode xfermodes.

Review URL: https://codereview.chromium.org/1334293003

9 files changed, 65 insertions, 338 deletions

diff --git a/src/effects/SkArithmeticMode.cpp b/src/effects/SkArithmeticMode.cpp
index 7db6b47d66..35ac8a84ba 100644
--- a/src/effects/SkArithmeticMode.cpp
+++ b/src/effects/SkArithmeticMode.cpp
@@ -31,8 +31,8 @@ public:
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkArithmeticMode_scalar)
 
 #if SK_SUPPORT_GPU
-    bool asFragmentProcessor(GrFragmentProcessor**, GrProcessorDataManager*,
-                             GrTexture* background) const override;
+    bool asFragmentProcessor(const GrFragmentProcessor**, GrProcessorDataManager*,
+                             const GrFragmentProcessor* dst) const override;
 
     bool asXPFactory(GrXPFactory**) const override;
 #endif
@@ -235,9 +235,9 @@ SkXfermode* SkArithmeticMode::Create(SkScalar k1, SkScalar k2,
 //////////////////////////////////////////////////////////////////////////////
 
 #if SK_SUPPORT_GPU
-bool SkArithmeticMode_scalar::asFragmentProcessor(GrFragmentProcessor** fp,
+bool SkArithmeticMode_scalar::asFragmentProcessor(const GrFragmentProcessor** fp,
                                                   GrProcessorDataManager* procDataManager,
-                                                  GrTexture* background) const {
+                                                  const GrFragmentProcessor* dst) const {
     if (fp) {
         *fp = GrArithmeticFP::Create(procDataManager,
                                      SkScalarToFloat(fK[0]),
@@ -245,7 +245,7 @@ bool SkArithmeticMode_scalar::asFragmentProcessor(GrFragmentProcessor** fp,
                                      SkScalarToFloat(fK[2]),
                                      SkScalarToFloat(fK[3]),
                                      fEnforcePMColor,
-                                     background);
+                                     dst);
     }
     return true;
 }
diff --git a/src/effects/SkArithmeticMode_gpu.cpp b/src/effects/SkArithmeticMode_gpu.cpp
index fd20b73cdc..5f149d0712 100644
--- a/src/effects/SkArithmeticMode_gpu.cpp
+++ b/src/effects/SkArithmeticMode_gpu.cpp
@@ -21,16 +21,16 @@
 static const bool gUseUnpremul = false;
 
 static void add_arithmetic_code(GrGLFragmentBuilder* fsBuilder,
-                                const char* inputColor,
+                                const char* srcColor,
                                 const char* dstColor,
                                 const char* outputColor,
                                 const char* kUni,
                                 bool enforcePMColor) {
     // We don't try to optimize for this case at all
-    if (nullptr == inputColor) {
+    if (nullptr == srcColor) {
         fsBuilder->codeAppend("const vec4 src = vec4(1);");
     } else {
-        fsBuilder->codeAppendf("vec4 src = %s;", inputColor);
+        fsBuilder->codeAppendf("vec4 src = %s;", srcColor);
         if (gUseUnpremul) {
             fsBuilder->codeAppend("src.rgb = clamp(src.rgb / src.a, 0.0, 1.0);");
         }
@@ -54,26 +54,21 @@ static void add_arithmetic_code(GrGLFragmentBuilder* fsBuilder,
 
 class GLArithmeticFP : public GrGLFragmentProcessor {
 public:
-    GLArithmeticFP(const GrProcessor&)
-        : fEnforcePMColor(true) {
-    }
+    GLArithmeticFP(const GrProcessor&) : fEnforcePMColor(true) {}
 
     ~GLArithmeticFP() override {}
 
     void emitCode(EmitArgs& args) override {
         GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
-        fsBuilder->codeAppend("vec4 bgColor = ");
-        fsBuilder->appendTextureLookup(args.fSamplers[0], args.fCoords[0].c_str(),
-                                       args.fCoords[0].getType());
-        fsBuilder->codeAppendf(";");
-        const char* dstColor = "bgColor";
+        fsBuilder->codeAppend("vec4 _dstColor;");
+        this->emitChild(0, nullptr, "_dstColor", args);
 
         fKUni = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
-                                    kVec4f_GrSLType, kDefault_GrSLPrecision,
-                                    "k");
+                                          kVec4f_GrSLType, kDefault_GrSLPrecision,
+                                          "k");
         const char* kUni = args.fBuilder->getUniformCStr(fKUni);
 
-        add_arithmetic_code(fsBuilder, args.fInputColor, dstColor, args.fOutputColor, kUni,
+        add_arithmetic_code(fsBuilder, args.fInputColor, "_dstColor", args.fOutputColor, kUni,
                             fEnforcePMColor);
     }
 
@@ -100,17 +95,13 @@ private:
 ///////////////////////////////////////////////////////////////////////////////
 
 GrArithmeticFP::GrArithmeticFP(GrProcessorDataManager*, float k1, float k2, float k3, float k4,
-                               bool enforcePMColor, GrTexture* background)
+                               bool enforcePMColor, const GrFragmentProcessor* dst)
   : fK1(k1), fK2(k2), fK3(k3), fK4(k4), fEnforcePMColor(enforcePMColor) {
     this->initClassID<GrArithmeticFP>();
 
-    SkASSERT(background);
-
-    fBackgroundTransform.reset(kLocal_GrCoordSet, background,
-                               GrTextureParams::kNone_FilterMode);
-    this->addCoordTransform(&fBackgroundTransform);
-    fBackgroundAccess.reset(background);
-    this->addTextureAccess(&fBackgroundAccess);
+    SkASSERT(dst);
+    SkDEBUGCODE(int dstIndex = )this->registerChildProcessor(dst);
+    SkASSERT(0 == dstIndex);
 }
 
 void GrArithmeticFP::onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const {
@@ -144,7 +135,8 @@ const GrFragmentProcessor* GrArithmeticFP::TestCreate(GrProcessorTestData* d) {
     float k4 = d->fRandom->nextF();
     bool enforcePMColor = d->fRandom->nextBool();
 
-    return new GrArithmeticFP(d->fProcDataManager, k1, k2, k3, k4, enforcePMColor, d->fTextures[0]);
+    SkAutoTUnref<const GrFragmentProcessor> dst(GrProcessorUnitTest::CreateChildFP(d));
+    return new GrArithmeticFP(d->fProcDataManager, k1, k2, k3, k4, enforcePMColor, dst);
 }
 
 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrArithmeticFP);
diff --git a/src/effects/SkArithmeticMode_gpu.h b/src/effects/SkArithmeticMode_gpu.h
index 7b343ee35f..d415cc4a49 100644
--- a/src/effects/SkArithmeticMode_gpu.h
+++ b/src/effects/SkArithmeticMode_gpu.h
@@ -31,10 +31,10 @@ class GrGLArtithmeticFP;
 
 class GrArithmeticFP : public GrFragmentProcessor {
 public:
-    static GrFragmentProcessor* Create(GrProcessorDataManager* procDataManager, float k1, float k2,
-                                       float k3, float k4, bool enforcePMColor,
-                                       GrTexture* background) {
-        return new GrArithmeticFP(procDataManager, k1, k2, k3, k4, enforcePMColor, background);
+    static const GrFragmentProcessor* Create(GrProcessorDataManager* procDataManager,
+                                             float k1, float k2, float k3, float k4,
+                                             bool enforcePMColor, const GrFragmentProcessor* dst) {
+        return new GrArithmeticFP(procDataManager, k1, k2, k3, k4, enforcePMColor, dst);
     }
 
     ~GrArithmeticFP() override {};
@@ -57,12 +57,10 @@ private:
     void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
 
     GrArithmeticFP(GrProcessorDataManager*, float k1, float k2, float k3, float k4,
-                   bool enforcePMColor, GrTexture* background);
+                   bool enforcePMColor, const GrFragmentProcessor* dst);
 
     float                       fK1, fK2, fK3, fK4;
     bool                        fEnforcePMColor;
-    GrCoordTransform            fBackgroundTransform;
-    GrTextureAccess             fBackgroundAccess;
 
     GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
     typedef GrFragmentProcessor INHERITED;
diff --git a/src/effects/SkColorCubeFilter.cpp b/src/effects/SkColorCubeFilter.cpp
index c5d4fc5a35..da5635cf71 100644
--- a/src/effects/SkColorCubeFilter.cpp
+++ b/src/effects/SkColorCubeFilter.cpp
@@ -304,7 +304,7 @@ void GrColorCubeEffect::GLProcessor::GenKey(const GrProcessor& proc,
 }
 
 bool SkColorCubeFilter::asFragmentProcessors(GrContext* context, GrProcessorDataManager*,
-                                             SkTDArray<GrFragmentProcessor*>* array) const {
+                                             SkTDArray<const GrFragmentProcessor*>* array) const {
     static const GrUniqueKey::Domain kDomain = GrUniqueKey::GenerateDomain();
     GrUniqueKey key;
     GrUniqueKey::Builder builder(&key, kDomain, 2);
diff --git a/src/effects/SkColorFilters.cpp b/src/effects/SkColorFilters.cpp
index c38328ccbb..ece3295107 100644
--- a/src/effects/SkColorFilters.cpp
+++ b/src/effects/SkColorFilters.cpp
@@ -65,305 +65,36 @@ SkFlattenable* SkModeColorFilter::CreateProc(SkReadBuffer& buffer) {
 ///////////////////////////////////////////////////////////////////////////////
 #if SK_SUPPORT_GPU
 #include "GrBlend.h"
-#include "GrFragmentProcessor.h"
 #include "GrInvariantOutput.h"
-#include "GrProcessorUnitTest.h"
+#include "effects/GrXfermodeFragmentProcessor.h"
+#include "effects/GrConstColorProcessor.h"
 #include "SkGr.h"
-#include "gl/GrGLFragmentProcessor.h"
-#include "gl/builders/GrGLProgramBuilder.h"
-
-namespace {
-/**
- * A definition of blend equation for one coefficient. Generates a
- * blend_coeff * value "expression".
- */
-template<typename ColorExpr>
-static inline ColorExpr blend_term(SkXfermode::Coeff coeff,
-                                   const ColorExpr& src,
-                                   const ColorExpr& dst,
-                                   const ColorExpr& value) {
-    switch (coeff) {
-    default:
-        SkFAIL("Unexpected xfer coeff.");
-    case SkXfermode::kZero_Coeff:    /** 0 */
-        return ColorExpr(0);
-    case SkXfermode::kOne_Coeff:     /** 1 */
-        return value;
-    case SkXfermode::kSC_Coeff:
-        return src * value;
-    case SkXfermode::kISC_Coeff:
-        return (ColorExpr(1) - src) * dst;
-    case SkXfermode::kDC_Coeff:
-        return dst * value;
-    case SkXfermode::kIDC_Coeff:
-        return (ColorExpr(1) - dst) * value;
-    case SkXfermode::kSA_Coeff:      /** src alpha */
-        return src.a() * value;
-    case SkXfermode::kISA_Coeff:     /** inverse src alpha (i.e. 1 - sa) */
-        return (typename ColorExpr::AExpr(1) - src.a()) * value;
-    case SkXfermode::kDA_Coeff:      /** dst alpha */
-        return dst.a() * value;
-    case SkXfermode::kIDA_Coeff:     /** inverse dst alpha (i.e. 1 - da) */
-        return (typename ColorExpr::AExpr(1) - dst.a()) *  value;
-    }
-}
-/**
- * Creates a color filter expression which modifies the color by
- * the specified color filter.
- */
-template <typename ColorExpr>
-static inline ColorExpr color_filter_expression(const SkXfermode::Mode& mode,
-                                                const ColorExpr& filterColor,
-                                                const ColorExpr& inColor) {
-    SkXfermode::Coeff colorCoeff;
-    SkXfermode::Coeff filterColorCoeff;
-    SkAssertResult(SkXfermode::ModeAsCoeff(mode, &filterColorCoeff, &colorCoeff));
-    return blend_term(colorCoeff, filterColor, inColor, inColor) +
-        blend_term(filterColorCoeff, filterColor, inColor, filterColor);
-}
-
-}
-
-class ModeColorFilterEffect : public GrFragmentProcessor {
-public:
-    static GrFragmentProcessor* Create(const GrColor& c, SkXfermode::Mode mode) {
-        // TODO: Make the effect take the coeffs rather than mode since we already do the
-        // conversion here.
-        SkXfermode::Coeff srcCoeff, dstCoeff;
-        if (!SkXfermode::ModeAsCoeff(mode, &srcCoeff, &dstCoeff)) {
-//            SkDebugf("Failing to create color filter for mode %d\n", mode);
-            return nullptr;
-        }
-        return new ModeColorFilterEffect(c, mode);
-    }
-
-    bool willUseFilterColor() const {
-        SkXfermode::Coeff dstCoeff;
-        SkXfermode::Coeff srcCoeff;
-        SkAssertResult(SkXfermode::ModeAsCoeff(fMode, &srcCoeff, &dstCoeff));
-        if (SkXfermode::kZero_Coeff == srcCoeff) {
-            return GrBlendCoeffRefsSrc(sk_blend_to_grblend(dstCoeff));
-        }
-        return true;
-    }
-
-    const char* name() const override { return "ModeColorFilterEffect"; }
-
-    SkXfermode::Mode mode() const { return fMode; }
-    GrColor color() const { return fColor; }
-
-    class GLProcessor : public GrGLFragmentProcessor {
-    public:
-        GLProcessor(const GrProcessor&) {
-        }
-
-        virtual void emitCode(EmitArgs& args) override {
-            SkXfermode::Mode mode = args.fFp.cast<ModeColorFilterEffect>().mode();
-
-            SkASSERT(SkXfermode::kDst_Mode != mode);
-            const char* colorFilterColorUniName = nullptr;
-            if (args.fFp.cast<ModeColorFilterEffect>().willUseFilterColor()) {
-                fFilterColorUni = args.fBuilder->addUniform(
-                                                      GrGLProgramBuilder::kFragment_Visibility,
-                                                      kVec4f_GrSLType, kDefault_GrSLPrecision,
-                                                      "FilterColor",
-                                                      &colorFilterColorUniName);
-            }
-
-            GrGLSLExpr4 filter =
-                color_filter_expression(mode, GrGLSLExpr4(colorFilterColorUniName),
-                                        GrGLSLExpr4(args.fInputColor));
-
-            args.fBuilder->getFragmentShaderBuilder()->
-                    codeAppendf("\t%s = %s;\n", args.fOutputColor, filter.c_str());
-        }
-
-        static void GenKey(const GrProcessor& fp, const GrGLSLCaps&,
-                           GrProcessorKeyBuilder* b) {
-            const ModeColorFilterEffect& colorModeFilter = fp.cast<ModeColorFilterEffect>();
-            // The SL code does not depend on filter color at the moment, so no need to represent it
-            // in the key.
-            b->add32(colorModeFilter.mode());
-        }
-
-    protected:
-        virtual void onSetData(const GrGLProgramDataManager& pdman,
-                             const GrProcessor& fp) override {
-            if (fFilterColorUni.isValid()) {
-                const ModeColorFilterEffect& colorModeFilter = fp.cast<ModeColorFilterEffect>();
-                GrGLfloat c[4];
-                GrColorToRGBAFloat(colorModeFilter.color(), c);
-                pdman.set4fv(fFilterColorUni, 1, c);
-            }
-        }
-
-    private:
-
-        GrGLProgramDataManager::UniformHandle fFilterColorUni;
-        typedef GrGLFragmentProcessor INHERITED;
-    };
-
-    GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
-
-private:
-    ModeColorFilterEffect(GrColor color, SkXfermode::Mode mode)
-        : fMode(mode),
-          fColor(color) {
-        this->initClassID<ModeColorFilterEffect>();
-    }
-
-    GrGLFragmentProcessor* onCreateGLInstance() const override { return new GLProcessor(*this); }
-
-    virtual void onGetGLProcessorKey(const GrGLSLCaps& caps,
-                                     GrProcessorKeyBuilder* b) const override {
-        GLProcessor::GenKey(*this, caps, b);
-    }
-
-    bool onIsEqual(const GrFragmentProcessor& other) const override {
-        const ModeColorFilterEffect& s = other.cast<ModeColorFilterEffect>();
-        return fMode == s.fMode && fColor == s.fColor;
-    }
-
-    void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
-
-    SkXfermode::Mode fMode;
-    GrColor fColor;
-
-    typedef GrFragmentProcessor INHERITED;
-};
-
-namespace {
-
-/** Function color_component_to_int tries to reproduce the GLSL rounding. The spec doesn't specify
- * to which direction the 0.5 goes.
- */
-static inline int color_component_to_int(float value) {
-    return sk_float_round2int(SkTMax(0.f, SkTMin(1.f, value)) * 255.f);
-}
-
-/** MaskedColorExpr is used to evaluate the color and valid color component flags through the
- * blending equation. It has members similar to GrGLSLExpr so that it can be used with the
- * templated helpers above.
- */
-class MaskedColorExpr {
-public:
-    MaskedColorExpr(const float color[], uint32_t flags)
-        : fFlags(flags) {
-        fColor[0] = color[0];
-        fColor[1] = color[1];
-        fColor[2] = color[2];
-        fColor[3] = color[3];
-    }
-
-    MaskedColorExpr(float v, uint32_t flags = kRGBA_GrColorComponentFlags)
-        : fFlags(flags) {
-        fColor[0] = v;
-        fColor[1] = v;
-        fColor[2] = v;
-        fColor[3] = v;
-    }
-
-    MaskedColorExpr operator*(const MaskedColorExpr& other) const {
-        float tmp[4];
-        tmp[0] = fColor[0] * other.fColor[0];
-        tmp[1] = fColor[1] * other.fColor[1];
-        tmp[2] = fColor[2] * other.fColor[2];
-        tmp[3] = fColor[3] * other.fColor[3];
-
-        return MaskedColorExpr(tmp, fFlags & other.fFlags);
-    }
-
-    MaskedColorExpr operator+(const MaskedColorExpr& other) const {
-        float tmp[4];
-        tmp[0] = fColor[0] + other.fColor[0];
-        tmp[1] = fColor[1] + other.fColor[1];
-        tmp[2] = fColor[2] + other.fColor[2];
-        tmp[3] = fColor[3] + other.fColor[3];
-
-        return MaskedColorExpr(tmp, fFlags & other.fFlags);
-    }
-
-    MaskedColorExpr operator-(const MaskedColorExpr& other) const {
-        float tmp[4];
-        tmp[0] = fColor[0] - other.fColor[0];
-        tmp[1] = fColor[1] - other.fColor[1];
-        tmp[2] = fColor[2] - other.fColor[2];
-        tmp[3] = fColor[3] - other.fColor[3];
-
-        return MaskedColorExpr(tmp, fFlags & other.fFlags);
-    }
-
-    MaskedColorExpr a() const {
-        uint32_t flags = (fFlags & kA_GrColorComponentFlag) ? kRGBA_GrColorComponentFlags : 0;
-        return MaskedColorExpr(fColor[3], flags);
-    }
-
-    GrColor getColor() const {
-        return GrColorPackRGBA(color_component_to_int(fColor[0]),
-                               color_component_to_int(fColor[1]),
-                               color_component_to_int(fColor[2]),
-                               color_component_to_int(fColor[3]));
-    }
-
-    uint32_t getValidComponents() const  { return fFlags; }
-
-    typedef MaskedColorExpr AExpr;
-private:
-    float fColor[4];
-    uint32_t fFlags;
-};
-
-}
-
-void ModeColorFilterEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
-    float inputColor[4];
-    GrColorToRGBAFloat(inout->color(), inputColor);
-    float filterColor[4];
-    GrColorToRGBAFloat(fColor, filterColor);
-    MaskedColorExpr result =
-        color_filter_expression(fMode,
-                                MaskedColorExpr(filterColor, kRGBA_GrColorComponentFlags),
-                                MaskedColorExpr(inputColor, inout->validFlags()));
-
-    // Check if we will use the input color
-    SkXfermode::Coeff dstCoeff;
-    SkXfermode::Coeff srcCoeff;
-    SkAssertResult(SkXfermode::ModeAsCoeff(fMode, &srcCoeff, &dstCoeff));
-    GrInvariantOutput::ReadInput readInput = GrInvariantOutput::kWill_ReadInput;
-    // These could be calculated from the blend equation with template trickery..
-    if (SkXfermode::kZero_Coeff == dstCoeff &&
-        !GrBlendCoeffRefsDst(sk_blend_to_grblend(srcCoeff))) {
-        readInput = GrInvariantOutput::kWillNot_ReadInput;
-    }
-    inout->setToOther(result.getValidComponents(), result.getColor(), readInput);
-}
-
-GR_DEFINE_FRAGMENT_PROCESSOR_TEST(ModeColorFilterEffect);
-const GrFragmentProcessor* ModeColorFilterEffect::TestCreate(GrProcessorTestData* d) {
-    SkXfermode::Mode mode = SkXfermode::kDst_Mode;
-    while (SkXfermode::kDst_Mode == mode) {
-        mode = static_cast<SkXfermode::Mode>(d->fRandom->nextRangeU(0, SkXfermode::kLastCoeffMode));
-    }
-
-    // pick a random premul color
-    uint8_t alpha = d->fRandom->nextULessThan(256);
-    GrColor color = GrColorPackRGBA(d->fRandom->nextRangeU(0, alpha),
-                                    d->fRandom->nextRangeU(0, alpha),
-                                    d->fRandom->nextRangeU(0, alpha),
-                                    alpha);
-    return ModeColorFilterEffect::Create(color, mode);
-}
 
 bool SkModeColorFilter::asFragmentProcessors(GrContext*, GrProcessorDataManager*,
-                                             SkTDArray<GrFragmentProcessor*>* array) const {
+                                             SkTDArray<const GrFragmentProcessor*>* array) const {
     if (SkXfermode::kDst_Mode != fMode) {
-        GrFragmentProcessor* frag = ModeColorFilterEffect::Create(SkColor2GrColor(fColor), fMode);
-        if (frag) {
+        SkAutoTUnref<const GrFragmentProcessor> constFP(
+            GrConstColorProcessor::Create(SkColor2GrColor(fColor),
+                                          GrConstColorProcessor::kIgnore_InputMode));
+        const GrFragmentProcessor* fp =
+            GrXfermodeFragmentProcessor::CreateFromSrcProcessor(constFP, fMode);
+        if (fp) {
+#ifdef SK_DEBUG
+            // With a solid color input this should always be able to compute the blended color
+            // (at least for coeff modes)
+            if (fMode <= SkXfermode::kLastCoeffMode) {
+                static SkRandom gRand;
+                GrInvariantOutput io(GrPremulColor(gRand.nextU()), kRGBA_GrColorComponentFlags,
+                                     false);
+                fp->computeInvariantOutput(&io);
+                SkASSERT(io.validFlags() == kRGBA_GrColorComponentFlags);
+            }
+#endif
             if (array) {
-                *array->append() = frag;
+                *array->append() = fp;
             } else {
-                frag->unref();
-                SkDEBUGCODE(frag = nullptr;)
+                fp->unref();
+                SkDEBUGCODE(fp = nullptr;)
             }
             return true;
         }
diff --git a/src/effects/SkColorMatrixFilter.cpp b/src/effects/SkColorMatrixFilter.cpp
index 1eedef1343..6131b264e7 100644
--- a/src/effects/SkColorMatrixFilter.cpp
+++ b/src/effects/SkColorMatrixFilter.cpp
@@ -537,7 +537,7 @@ const GrFragmentProcessor* ColorMatrixEffect::TestCreate(GrProcessorTestData* d)
 }
 
 bool SkColorMatrixFilter::asFragmentProcessors(GrContext*, GrProcessorDataManager*,
-                                               SkTDArray<GrFragmentProcessor*>* array) const {
+                                               SkTDArray<const GrFragmentProcessor*>* array) const {
     GrFragmentProcessor* frag = ColorMatrixEffect::Create(fMatrix);
     if (frag) {
         if (array) {
diff --git a/src/effects/SkLumaColorFilter.cpp b/src/effects/SkLumaColorFilter.cpp
index e161d170b2..7e16f3ac89 100644
--- a/src/effects/SkLumaColorFilter.cpp
+++ b/src/effects/SkLumaColorFilter.cpp
@@ -109,7 +109,7 @@ private:
 };
 
 bool SkLumaColorFilter::asFragmentProcessors(GrContext*, GrProcessorDataManager*,
-                                             SkTDArray<GrFragmentProcessor*>* array) const {
+                                             SkTDArray<const GrFragmentProcessor*>* array) const {
 
     GrFragmentProcessor* frag = LumaColorFilterEffect::Create();
     if (frag) {
diff --git a/src/effects/SkTableColorFilter.cpp b/src/effects/SkTableColorFilter.cpp
index 1a2b1343b6..85e3a317bb 100644
--- a/src/effects/SkTableColorFilter.cpp
+++ b/src/effects/SkTableColorFilter.cpp
@@ -49,7 +49,7 @@ public:
 
 #if SK_SUPPORT_GPU
     bool asFragmentProcessors(GrContext*, GrProcessorDataManager*,
-                              SkTDArray<GrFragmentProcessor*>*) const override;
+                              SkTDArray<const GrFragmentProcessor*>*) const override;
 #endif
 
     void filterSpan(const SkPMColor src[], int count, SkPMColor dst[]) const override;
@@ -521,7 +521,7 @@ bool ColorTableEffect::onIsEqual(const GrFragmentProcessor& other) const {
 void ColorTableEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
     // If we kept the table in the effect then we could actually run known inputs through the
     // table.
-    uint8_t invalidateFlags = 0;
+    GrColorComponentFlags invalidateFlags = kNone_GrColorComponentFlags;
     if (fFlags & SkTable_ColorFilter::kR_Flag) {
         invalidateFlags |= kR_GrColorComponentFlag;
     }
@@ -563,7 +563,7 @@ const GrFragmentProcessor* ColorTableEffect::TestCreate(GrProcessorTestData* d)
         (flags & (1 << 3)) ? luts[3] : nullptr
     ));
 
-    SkTDArray<GrFragmentProcessor*> array;
+    SkTDArray<const GrFragmentProcessor*> array;
     if (filter->asFragmentProcessors(d->fContext, d->fProcDataManager, &array)) {
         SkASSERT(1 == array.count());   // TableColorFilter only returns 1
         return array[0];
@@ -573,7 +573,7 @@ const GrFragmentProcessor* ColorTableEffect::TestCreate(GrProcessorTestData* d)
 
 bool SkTable_ColorFilter::asFragmentProcessors(GrContext* context,
                                                GrProcessorDataManager*,
-                                               SkTDArray<GrFragmentProcessor*>* array) const {
+                                               SkTDArray<const GrFragmentProcessor*>* array) const {
     SkBitmap bitmap;
     this->asComponentTable(&bitmap);
 
diff --git a/src/effects/SkXfermodeImageFilter.cpp b/src/effects/SkXfermodeImageFilter.cpp
index 9ffbe62bdc..e357b0f23d 100644
--- a/src/effects/SkXfermodeImageFilter.cpp
+++ b/src/effects/SkXfermodeImageFilter.cpp
@@ -16,6 +16,7 @@
 #include "GrContext.h"
 #include "GrDrawContext.h"
 #include "effects/GrTextureDomain.h"
+#include "effects/GrSimpleTextureEffect.h"
 #include "SkGr.h"
 #endif
 
@@ -153,7 +154,7 @@ bool SkXfermodeImageFilter::filterImageGPU(Proxy* proxy,
     GrTexture* foregroundTex = foreground.getTexture();
     GrContext* context = foregroundTex->getContext();
 
-    GrFragmentProcessor* xferProcessor = nullptr;
+    const GrFragmentProcessor* xferFP = nullptr;
 
     GrSurfaceDesc desc;
     desc.fFlags = kRenderTarget_GrSurfaceFlag;
@@ -166,8 +167,11 @@ bool SkXfermodeImageFilter::filterImageGPU(Proxy* proxy,
     }
 
     GrPaint paint;
-    if (!fMode || !fMode->asFragmentProcessor(&xferProcessor, paint.getProcessorDataManager(),
-                                              backgroundTex)) {
+    SkMatrix bgMatrix;
+    bgMatrix.setIDiv(backgroundTex->width(), backgroundTex->height());
+    SkAutoTUnref<const GrFragmentProcessor> bgFP(
+        GrSimpleTextureEffect::Create(paint.getProcessorDataManager(), backgroundTex, bgMatrix));
+    if (!fMode || !fMode->asFragmentProcessor(&xferFP, paint.getProcessorDataManager(), bgFP)) {
         // canFilterImageGPU() should've taken care of this
         SkASSERT(false);
         return false;
@@ -190,7 +194,9 @@ bool SkXfermodeImageFilter::filterImageGPU(Proxy* proxy,
     );
 
     paint.addColorFragmentProcessor(foregroundDomain.get());
-    paint.addColorFragmentProcessor(xferProcessor)->unref();
+    if (xferFP) {
+        paint.addColorFragmentProcessor(xferFP)->unref();
+    }
 
     SkAutoTUnref<GrDrawContext> drawContext(context->drawContext());
     if (!drawContext) {