Create fragment processor for performing input color blend with child processor

src/gpu/effects/GrCustomXfermode.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "effects/GrCustomXfermode.h"
 #include "effects/GrCustomXfermodePriv.h"
 
 #include "GrCoordTransform.h"
 #include "GrContext.h"
 #include "GrFragmentProcessor.h"
 #include "GrInvariantOutput.h"
 #include "GrProcessor.h"
 #include "GrTexture.h"
 #include "GrTextureAccess.h"
 #include "SkXfermode.h"
 #include "gl/GrGLCaps.h"
 #include "gl/GrGLGpu.h"
+#include "gl/GrGLSLBlend.h"
 #include "gl/GrGLFragmentProcessor.h"
 #include "gl/GrGLProgramDataManager.h"
 #include "gl/builders/GrGLProgramBuilder.h"
 #include "glsl/GrGLSLCaps.h"
 
 bool GrCustomXfermode::IsSupportedMode(SkXfermode::Mode mode) {
     return mode > SkXfermode::kLastCoeffMode && mode <= SkXfermode::kLastMode;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ skipping 29 matching lines @@
     }
     if (coveragePOI.isFourChannelOutput()) {
         return false; // LCD coverage must be applied after the blend equation.
     }
     if (caps.canUseAdvancedBlendEquation(equation)) {
         return false;
     }
     return true;
 }
 
-static void hard_light(GrGLFragmentBuilder* fsBuilder,
-                       const char* final,
-                       const char* src,
-                       const char* dst) {
-    static const char kComponents[] = {'r', 'g', 'b'};
-    for (size_t i = 0; i < SK_ARRAY_COUNT(kComponents); ++i) {
-        char component = kComponents[i];
-        fsBuilder->codeAppendf("if (2.0 * %s.%c <= %s.a) {", src, component, src);
-        fsBuilder->codeAppendf("%s.%c = 2.0 * %s.%c * %s.%c;",
-                               final, component, src, component, dst, component);
-        fsBuilder->codeAppend("} else {");
-        fsBuilder->codeAppendf("%s.%c = %s.a * %s.a - 2.0 * (%s.a - %s.%c) * (%s.a - %s.%c);",
-                               final, component, src, dst, dst, dst, component, src, src,
-                               component);
-        fsBuilder->codeAppend("}");
-    }
-    fsBuilder->codeAppendf("%s.rgb += %s.rgb * (1.0 - %s.a) + %s.rgb * (1.0 - %s.a);",
-                           final, src, dst, dst, src);
-}
-
-// Does one component of color-dodge
-static void color_dodge_component(GrGLFragmentBuilder* fsBuilder,
-                                  const char* final,
-                                  const char* src,
-                                  const char* dst,
-                                  const char component) {
-    fsBuilder->codeAppendf("if (0.0 == %s.%c) {", dst, component);
-    fsBuilder->codeAppendf("%s.%c = %s.%c * (1.0 - %s.a);",
-                           final, component, src, component, dst);
-    fsBuilder->codeAppend("} else {");
-    fsBuilder->codeAppendf("float d = %s.a - %s.%c;", src, src, component);
-    fsBuilder->codeAppend("if (0.0 == d) {");
-    fsBuilder->codeAppendf("%s.%c = %s.a * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
-                           final, component, src, dst, src, component, dst, dst, component,
-                           src);
-    fsBuilder->codeAppend("} else {");
-    fsBuilder->codeAppendf("d = min(%s.a, %s.%c * %s.a / d);",
-                           dst, dst, component, src);
-    fsBuilder->codeAppendf("%s.%c = d * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
-                           final, component, src, src, component, dst, dst, component, src);
-    fsBuilder->codeAppend("}");
-    fsBuilder->codeAppend("}");
-}
-
-// Does one component of color-burn
-static void color_burn_component(GrGLFragmentBuilder* fsBuilder,
-                                 const char* final,
-                                 const char* src,
-                                 const char* dst,
-                                 const char component) {
-    fsBuilder->codeAppendf("if (%s.a == %s.%c) {", dst, dst, component);
-    fsBuilder->codeAppendf("%s.%c = %s.a * %s.a + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
-                           final, component, src, dst, src, component, dst, dst, component,
-                           src);
-    fsBuilder->codeAppendf("} else if (0.0 == %s.%c) {", src, component);
-    fsBuilder->codeAppendf("%s.%c = %s.%c * (1.0 - %s.a);",
-                           final, component, dst, component, src);
-    fsBuilder->codeAppend("} else {");
-    fsBuilder->codeAppendf("float d = max(0.0, %s.a - (%s.a - %s.%c) * %s.a / %s.%c);",
-                           dst, dst, dst, component, src, src, component);
-    fsBuilder->codeAppendf("%s.%c = %s.a * d + %s.%c * (1.0 - %s.a) + %s.%c * (1.0 - %s.a);",
-                           final, component, src, src, component, dst, dst, component, src);
-    fsBuilder->codeAppend("}");
-}
-
-// Does one component of soft-light. Caller should have already checked that dst alpha > 0.
-static void soft_light_component_pos_dst_alpha(GrGLFragmentBuilder* fsBuilder,
-                                               const char* final,
-                                               const char* src,
-                                               const char* dst,
-                                               const char component) {
-    // if (2S < Sa)
-    fsBuilder->codeAppendf("if (2.0 * %s.%c <= %s.a) {", src, component, src);
-    // (D^2 (Sa-2 S))/Da+(1-Da) S+D (-Sa+2 S+1)
-    fsBuilder->codeAppendf("%s.%c = (%s.%c*%s.%c*(%s.a - 2.0*%s.%c)) / %s.a +"
-                                   "(1.0 - %s.a) * %s.%c + %s.%c*(-%s.a + 2.0*%s.%c + 1.0);",
-                           final, component, dst, component, dst, component, src, src,
-                           component, dst, dst, src, component, dst, component, src, src,
-                           component);
-    // else if (4D < Da)
-    fsBuilder->codeAppendf("} else if (4.0 * %s.%c <= %s.a) {",
-                           dst, component, dst);
-    fsBuilder->codeAppendf("float DSqd = %s.%c * %s.%c;",
-                           dst, component, dst, component);
-    fsBuilder->codeAppendf("float DCub = DSqd * %s.%c;", dst, component);
-    fsBuilder->codeAppendf("float DaSqd = %s.a * %s.a;", dst, dst);
-    fsBuilder->codeAppendf("float DaCub = DaSqd * %s.a;", dst);
-    // (Da^3 (-S)+Da^2 (S-D (3 Sa-6 S-1))+12 Da D^2 (Sa-2 S)-16 D^3 (Sa-2 S))/Da^2
-    fsBuilder->codeAppendf("%s.%c ="
-                           "(DaSqd*(%s.%c - %s.%c * (3.0*%s.a - 6.0*%s.%c - 1.0)) +"
-                           " 12.0*%s.a*DSqd*(%s.a - 2.0*%s.%c) - 16.0*DCub * (%s.a - 2.0*%s.%c) -"
-                           " DaCub*%s.%c) / DaSqd;",
-                           final, component, src, component, dst, component,
-                           src, src, component, dst, src, src, component, src, src,
-                           component, src, component);
-    fsBuilder->codeAppendf("} else {");
-    // -sqrt(Da * D) (Sa-2 S)-Da S+D (Sa-2 S+1)+S
-    fsBuilder->codeAppendf("%s.%c = %s.%c*(%s.a - 2.0*%s.%c + 1.0) + %s.%c -"
-                           " sqrt(%s.a*%s.%c)*(%s.a - 2.0*%s.%c) - %s.a*%s.%c;",
-                           final, component, dst, component, src, src, component, src, component,
-                           dst, dst, component, src, src, component, dst, src, component);
-    fsBuilder->codeAppendf("}");
-}
-
-// Adds a function that takes two colors and an alpha as input. It produces a color with the
-// hue and saturation of the first color, the luminosity of the second color, and the input
-// alpha. It has this signature:
-//      vec3 set_luminance(vec3 hueSatColor, float alpha, vec3 lumColor).
-static void add_lum_function(GrGLFragmentBuilder* fsBuilder, SkString* setLumFunction) {
-    // Emit a helper that gets the luminance of a color.
-    SkString getFunction;
-    GrGLShaderVar getLumArgs[] = {
-        GrGLShaderVar("color", kVec3f_GrSLType),
-    };
-    SkString getLumBody("return dot(vec3(0.3, 0.59, 0.11), color);");
-    fsBuilder->emitFunction(kFloat_GrSLType,
-                            "luminance",
-                            SK_ARRAY_COUNT(getLumArgs), getLumArgs,
-                            getLumBody.c_str(),
-                            &getFunction);
-
-    // Emit the set luminance function.
-    GrGLShaderVar setLumArgs[] = {
-        GrGLShaderVar("hueSat", kVec3f_GrSLType),
-        GrGLShaderVar("alpha", kFloat_GrSLType),
-        GrGLShaderVar("lumColor", kVec3f_GrSLType),
-    };
-    SkString setLumBody;
-    setLumBody.printf("float diff = %s(lumColor - hueSat);", getFunction.c_str());
-    setLumBody.append("vec3 outColor = hueSat + diff;");
-    setLumBody.appendf("float outLum = %s(outColor);", getFunction.c_str());
-    setLumBody.append("float minComp = min(min(outColor.r, outColor.g), outColor.b);"
-                      "float maxComp = max(max(outColor.r, outColor.g), outColor.b);"
-                      "if (minComp < 0.0 && outLum != minComp) {"
-                      "outColor = outLum + ((outColor - vec3(outLum, outLum, outLum)) * outLum) /"
-                                          "(outLum - minComp);"
-                      "}"
-                      "if (maxComp > alpha && maxComp != outLum) {"
-                      "outColor = outLum +"
-                                 "((outColor - vec3(outLum, outLum, outLum)) * (alpha - outLum)) /"
-                                 "(maxComp - outLum);"
-                      "}"
-                      "return outColor;");
-    fsBuilder->emitFunction(kVec3f_GrSLType,
-                            "set_luminance",
-                            SK_ARRAY_COUNT(setLumArgs), setLumArgs,
-                            setLumBody.c_str(),
-                            setLumFunction);
-}
-
-// Adds a function that creates a color with the hue and luminosity of one input color and
-// the saturation of another color. It will have this signature:
-//      float set_saturation(vec3 hueLumColor, vec3 satColor)
-static void add_sat_function(GrGLFragmentBuilder* fsBuilder, SkString* setSatFunction) {
-    // Emit a helper that gets the saturation of a color
-    SkString getFunction;
-    GrGLShaderVar getSatArgs[] = { GrGLShaderVar("color", kVec3f_GrSLType) };
-    SkString getSatBody;
-    getSatBody.printf("return max(max(color.r, color.g), color.b) - "
-                      "min(min(color.r, color.g), color.b);");
-    fsBuilder->emitFunction(kFloat_GrSLType,
-                            "saturation",
-                            SK_ARRAY_COUNT(getSatArgs), getSatArgs,
-                            getSatBody.c_str(),
-                            &getFunction);
-
-    // Emit a helper that sets the saturation given sorted input channels. This used
-    // to use inout params for min, mid, and max components but that seems to cause
-    // problems on PowerVR drivers. So instead it returns a vec3 where r, g ,b are the
-    // adjusted min, mid, and max inputs, respectively.
-    SkString helperFunction;
-    GrGLShaderVar helperArgs[] = {
-        GrGLShaderVar("minComp", kFloat_GrSLType),
-        GrGLShaderVar("midComp", kFloat_GrSLType),
-        GrGLShaderVar("maxComp", kFloat_GrSLType),
-        GrGLShaderVar("sat", kFloat_GrSLType),
-    };
-    static const char kHelperBody[] = "if (minComp < maxComp) {"
-        "vec3 result;"
-        "result.r = 0.0;"
-        "result.g = sat * (midComp - minComp) / (maxComp - minComp);"
-        "result.b = sat;"
-        "return result;"
-        "} else {"
-        "return vec3(0, 0, 0);"
-        "}";
-    fsBuilder->emitFunction(kVec3f_GrSLType,
-                            "set_saturation_helper",
-                            SK_ARRAY_COUNT(helperArgs), helperArgs,
-                            kHelperBody,
-                            &helperFunction);
-
-    GrGLShaderVar setSatArgs[] = {
-        GrGLShaderVar("hueLumColor", kVec3f_GrSLType),
-        GrGLShaderVar("satColor", kVec3f_GrSLType),
-    };
-    const char* helpFunc = helperFunction.c_str();
-    SkString setSatBody;
-    setSatBody.appendf("float sat = %s(satColor);"
-                       "if (hueLumColor.r <= hueLumColor.g) {"
-                       "if (hueLumColor.g <= hueLumColor.b) {"
-                       "hueLumColor.rgb = %s(hueLumColor.r, hueLumColor.g, hueLumColor.b, sat);"
-                       "} else if (hueLumColor.r <= hueLumColor.b) {"
-                       "hueLumColor.rbg = %s(hueLumColor.r, hueLumColor.b, hueLumColor.g, sat);"
-                       "} else {"
-                       "hueLumColor.brg = %s(hueLumColor.b, hueLumColor.r, hueLumColor.g, sat);"
-                       "}"
-                       "} else if (hueLumColor.r <= hueLumColor.b) {"
-                       "hueLumColor.grb = %s(hueLumColor.g, hueLumColor.r, hueLumColor.b, sat);"
-                       "} else if (hueLumColor.g <= hueLumColor.b) {"
-                       "hueLumColor.gbr = %s(hueLumColor.g, hueLumColor.b, hueLumColor.r, sat);"
-                       "} else {"
-                       "hueLumColor.bgr = %s(hueLumColor.b, hueLumColor.g, hueLumColor.r, sat);"
-                       "}"
-                       "return hueLumColor;",
-                       getFunction.c_str(), helpFunc, helpFunc, helpFunc, helpFunc,
-                       helpFunc, helpFunc);
-    fsBuilder->emitFunction(kVec3f_GrSLType,
-                            "set_saturation",
-                            SK_ARRAY_COUNT(setSatArgs), setSatArgs,
-                            setSatBody.c_str(),
-                            setSatFunction);
-
-}
-
-static void emit_custom_xfermode_code(SkXfermode::Mode mode,
-                                      GrGLFragmentBuilder* fsBuilder,
-                                      const char* outputColor,
-                                      const char* inputColor,
-                                      const char* dstColor) {
-    // We don't try to optimize for this case at all
-    if (nullptr == inputColor) {
-        fsBuilder->codeAppendf("const vec4 ones = vec4(1);");
-        inputColor = "ones";
-    }
-    fsBuilder->codeAppendf("// SkXfermode::Mode: %s\n", SkXfermode::ModeName(mode));
-
-    // These all perform src-over on the alpha channel.
-    fsBuilder->codeAppendf("%s.a = %s.a + (1.0 - %s.a) * %s.a;",
-                           outputColor, inputColor, inputColor, dstColor);
-
-    switch (mode) {
-        case SkXfermode::kOverlay_Mode:
-            // Overlay is Hard-Light with the src and dst reversed
-            hard_light(fsBuilder, outputColor, dstColor, inputColor);
-            break;
-        case SkXfermode::kDarken_Mode:
-            fsBuilder->codeAppendf("%s.rgb = min((1.0 - %s.a) * %s.rgb + %s.rgb, "
-                                   "(1.0 - %s.a) * %s.rgb + %s.rgb);",
-                                   outputColor,
-                                   inputColor, dstColor, inputColor,
-                                   dstColor, inputColor, dstColor);
-            break;
-        case SkXfermode::kLighten_Mode:
-            fsBuilder->codeAppendf("%s.rgb = max((1.0 - %s.a) * %s.rgb + %s.rgb, "
-                                   "(1.0 - %s.a) * %s.rgb + %s.rgb);",
-                                   outputColor,
-                                   inputColor, dstColor, inputColor,
-                                   dstColor, inputColor, dstColor);
-            break;
-        case SkXfermode::kColorDodge_Mode:
-            color_dodge_component(fsBuilder, outputColor, inputColor, dstColor, 'r');
-            color_dodge_component(fsBuilder, outputColor, inputColor, dstColor, 'g');
-            color_dodge_component(fsBuilder, outputColor, inputColor, dstColor, 'b');
-            break;
-        case SkXfermode::kColorBurn_Mode:
-            color_burn_component(fsBuilder, outputColor, inputColor, dstColor, 'r');
-            color_burn_component(fsBuilder, outputColor, inputColor, dstColor, 'g');
-            color_burn_component(fsBuilder, outputColor, inputColor, dstColor, 'b');
-            break;
-        case SkXfermode::kHardLight_Mode:
-            hard_light(fsBuilder, outputColor, inputColor, dstColor);
-            break;
-        case SkXfermode::kSoftLight_Mode:
-            fsBuilder->codeAppendf("if (0.0 == %s.a) {", dstColor);
-            fsBuilder->codeAppendf("%s.rgba = %s;", outputColor, inputColor);
-            fsBuilder->codeAppendf("} else {");
-            soft_light_component_pos_dst_alpha(fsBuilder, outputColor, inputColor, dstColor, 'r');
-            soft_light_component_pos_dst_alpha(fsBuilder, outputColor, inputColor, dstColor, 'g');
-            soft_light_component_pos_dst_alpha(fsBuilder, outputColor, inputColor, dstColor, 'b');
-            fsBuilder->codeAppendf("}");
-            break;
-        case SkXfermode::kDifference_Mode:
-            fsBuilder->codeAppendf("%s.rgb = %s.rgb + %s.rgb -"
-                                   "2.0 * min(%s.rgb * %s.a, %s.rgb * %s.a);",
-                                   outputColor, inputColor, dstColor, inputColor, dstColor,
-                                   dstColor, inputColor);
-            break;
-        case SkXfermode::kExclusion_Mode:
-            fsBuilder->codeAppendf("%s.rgb = %s.rgb + %s.rgb - "
-                                   "2.0 * %s.rgb * %s.rgb;",
-                                   outputColor, dstColor, inputColor, dstColor, inputColor);
-            break;
-        case SkXfermode::kMultiply_Mode:
-            fsBuilder->codeAppendf("%s.rgb = (1.0 - %s.a) * %s.rgb + "
-                                   "(1.0 - %s.a) * %s.rgb + "
-                                   "%s.rgb * %s.rgb;",
-                                   outputColor, inputColor, dstColor, dstColor, inputColor,
-                                   inputColor, dstColor);
-            break;
-        case SkXfermode::kHue_Mode: {
-            //  SetLum(SetSat(S * Da, Sat(D * Sa)), Sa*Da, D*Sa) + (1 - Sa) * D + (1 - Da) * S
-            SkString setSat, setLum;
-            add_sat_function(fsBuilder, &setSat);
-            add_lum_function(fsBuilder, &setLum);
-            fsBuilder->codeAppendf("vec4 dstSrcAlpha = %s * %s.a;",
-                                   dstColor, inputColor);
-            fsBuilder->codeAppendf("%s.rgb = %s(%s(%s.rgb * %s.a, dstSrcAlpha.rgb),"
-                                               "dstSrcAlpha.a, dstSrcAlpha.rgb);",
-                                   outputColor, setLum.c_str(), setSat.c_str(), inputColor,
-                                   dstColor);
-            fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
-                                   outputColor, inputColor, dstColor, dstColor, inputColor);
-            break;
-        }
-        case SkXfermode::kSaturation_Mode: {
-            // SetLum(SetSat(D * Sa, Sat(S * Da)), Sa*Da, D*Sa)) + (1 - Sa) * D + (1 - Da) * S
-            SkString setSat, setLum;
-            add_sat_function(fsBuilder, &setSat);
-            add_lum_function(fsBuilder, &setLum);
-            fsBuilder->codeAppendf("vec4 dstSrcAlpha = %s * %s.a;",
-                                   dstColor, inputColor);
-            fsBuilder->codeAppendf("%s.rgb = %s(%s(dstSrcAlpha.rgb, %s.rgb * %s.a),"
-                                               "dstSrcAlpha.a, dstSrcAlpha.rgb);",
-                                   outputColor, setLum.c_str(), setSat.c_str(), inputColor,
-                                   dstColor);
-            fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
-                                   outputColor, inputColor, dstColor, dstColor, inputColor);
-            break;
-        }
-        case SkXfermode::kColor_Mode: {
-            //  SetLum(S * Da, Sa* Da, D * Sa) + (1 - Sa) * D + (1 - Da) * S
-            SkString setLum;
-            add_lum_function(fsBuilder, &setLum);
-            fsBuilder->codeAppendf("vec4 srcDstAlpha = %s * %s.a;",
-                                   inputColor, dstColor);
-            fsBuilder->codeAppendf("%s.rgb = %s(srcDstAlpha.rgb, srcDstAlpha.a, %s.rgb * %s.a);",
-                                   outputColor, setLum.c_str(), dstColor, inputColor);
-            fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
-                                   outputColor, inputColor, dstColor, dstColor, inputColor);
-            break;
-        }
-        case SkXfermode::kLuminosity_Mode: {
-            //  SetLum(D * Sa, Sa* Da, S * Da) + (1 - Sa) * D + (1 - Da) * S
-            SkString setLum;
-            add_lum_function(fsBuilder, &setLum);
-            fsBuilder->codeAppendf("vec4 srcDstAlpha = %s * %s.a;",
-                                   inputColor, dstColor);
-            fsBuilder->codeAppendf("%s.rgb = %s(%s.rgb * %s.a, srcDstAlpha.a, srcDstAlpha.rgb);",
-                                   outputColor, setLum.c_str(), dstColor, inputColor);
-            fsBuilder->codeAppendf("%s.rgb += (1.0 - %s.a) * %s.rgb + (1.0 - %s.a) * %s.rgb;",
-                                   outputColor, inputColor, dstColor, dstColor, inputColor);
-            break;
-        }
-        default:
-            SkFAIL("Unknown Custom Xfer mode.");
-            break;
-    }
-}
-
-///////////////////////////////////////////////////////////////////////////////
-// Fragment Processor
-///////////////////////////////////////////////////////////////////////////////
-
-GrFragmentProcessor* GrCustomXfermode::CreateFP(GrProcessorDataManager* procDataManager,
-                                                SkXfermode::Mode mode, GrTexture* background) {
-    if (!GrCustomXfermode::IsSupportedMode(mode)) {
-        return nullptr;
-    } else {
-        return new GrCustomXferFP(procDataManager, mode, background);
-    }
-}
-
-///////////////////////////////////////////////////////////////////////////////
-
-class GLCustomXferFP : public GrGLFragmentProcessor {
-public:
-    GLCustomXferFP(const GrFragmentProcessor&) {}
-    ~GLCustomXferFP() override {};
-
-    void emitCode(EmitArgs& args) override {
-        SkXfermode::Mode mode = args.fFp.cast<GrCustomXferFP>().mode();
-        GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
-        const char* dstColor = "bgColor";
-        fsBuilder->codeAppendf("vec4 %s = ", dstColor);
-        fsBuilder->appendTextureLookup(args.fSamplers[0], args.fCoords[0].c_str(),
-                                       args.fCoords[0].getType());
-        fsBuilder->codeAppendf(";");
-
-        emit_custom_xfermode_code(mode, fsBuilder, args.fOutputColor, args.fInputColor, dstColor);
-    }
-
-    static void GenKey(const GrFragmentProcessor& proc, const GrGLSLCaps&, GrProcessorKeyBuilder* b) {
-        // The background may come from the dst or from a texture.
-        uint32_t key = proc.numTextures();
-        SkASSERT(key <= 1);
-        key |= proc.cast<GrCustomXferFP>().mode() << 1;
-        b->add32(key);
-    }
-
-protected:
-    void onSetData(const GrGLProgramDataManager&, const GrProcessor&) override {}
-
-private:
-    typedef GrGLFragmentProcessor INHERITED;
-};
-
-///////////////////////////////////////////////////////////////////////////////
-
-GrCustomXferFP::GrCustomXferFP(GrProcessorDataManager*, SkXfermode::Mode mode, GrTexture* background)
-    : fMode(mode) {
-    this->initClassID<GrCustomXferFP>();
-
-    SkASSERT(background);
-    fBackgroundTransform.reset(kLocal_GrCoordSet, background, 
-                               GrTextureParams::kNone_FilterMode);
-    this->addCoordTransform(&fBackgroundTransform);
-    fBackgroundAccess.reset(background);
-    this->addTextureAccess(&fBackgroundAccess);
-}
-
-void GrCustomXferFP::onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const {
-    GLCustomXferFP::GenKey(*this, caps, b);
-}
-
-GrGLFragmentProcessor* GrCustomXferFP::onCreateGLInstance() const {
-    return new GLCustomXferFP(*this);
-}
-
-bool GrCustomXferFP::onIsEqual(const GrFragmentProcessor& other) const {
-    const GrCustomXferFP& s = other.cast<GrCustomXferFP>();
-    return fMode == s.fMode;
-}
-
-void GrCustomXferFP::onComputeInvariantOutput(GrInvariantOutput* inout) const {
-    inout->setToUnknown(GrInvariantOutput::kWill_ReadInput);
-}
-
-GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrCustomXferFP);
-const GrFragmentProcessor* GrCustomXferFP::TestCreate(GrProcessorTestData* d) {
-    int mode = d->fRandom->nextRangeU(SkXfermode::kLastCoeffMode + 1, SkXfermode::kLastSeparableMode);
-
-    return new GrCustomXferFP(d->fProcDataManager, static_cast<SkXfermode::Mode>(mode),
-                              d->fTextures[0]);
-}
-
 ///////////////////////////////////////////////////////////////////////////////
 // Xfer Processor
 ///////////////////////////////////////////////////////////////////////////////
 
 class CustomXP : public GrXferProcessor {
 public:
     CustomXP(SkXfermode::Mode mode, GrBlendEquation hwBlendEquation)
         : fMode(mode),
           fHWBlendEquation(hwBlendEquation) {
         this->initClassID<CustomXP>();
@@ skipping 88 matching lines @@
             fsBuilder->codeAppendf("%s = %s;", args.fOutputPrimary, args.fInputColor);
         }
     }
 
     void emitBlendCodeForDstRead(GrGLXPBuilder* pb, const char* srcColor, const char* dstColor,
                                  const char* outColor, const GrXferProcessor& proc) override {
         const CustomXP& xp = proc.cast<CustomXP>();
         SkASSERT(!xp.hasHWBlendEquation());
 
         GrGLXPFragmentBuilder* fsBuilder = pb->getFragmentShaderBuilder();
-        emit_custom_xfermode_code(xp.mode(), fsBuilder, outColor, srcColor, dstColor);
+        GrGLSLBlend::AppendMode(fsBuilder, srcColor, dstColor, outColor, xp.mode());
     }
 
     void onSetData(const GrGLProgramDataManager&, const GrXferProcessor&) override {}
 
     typedef GrGLXferProcessor INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 void CustomXP::onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const {
@@ skipping 170 matching lines @@
 }
 
 GR_DEFINE_XP_FACTORY_TEST(GrCustomXPFactory);
 const GrXPFactory* GrCustomXPFactory::TestCreate(GrProcessorTestData* d) {
     int mode = d->fRandom->nextRangeU(SkXfermode::kLastCoeffMode + 1,
                                       SkXfermode::kLastSeparableMode);
 
     return new GrCustomXPFactory(static_cast<SkXfermode::Mode>(mode));
 }