C++ GrGLSLFPFragmentBuilder::appendTextureLookup方法代码示例

void GrColorCubeEffect::GLSLProcessor::emitCode(EmitArgs& args) {
    if (nullptr == args.fInputColor) {
        args.fInputColor = "vec4(1)";
    }

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fColorCubeSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                   kFloat_GrSLType, kDefault_GrSLPrecision,
                                                   "Size");
    const char* colorCubeSizeUni = uniformHandler->getUniformCStr(fColorCubeSizeUni);
    fColorCubeInvSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                      kFloat_GrSLType, kDefault_GrSLPrecision,
                                                      "InvSize");
    const char* colorCubeInvSizeUni = uniformHandler->getUniformCStr(fColorCubeInvSizeUni);

    const char* nonZeroAlpha = "nonZeroAlpha";
    const char* unPMColor = "unPMColor";
    const char* cubeIdx = "cubeIdx";
    const char* cCoords1 = "cCoords1";
    const char* cCoords2 = "cCoords2";

    // Note: if implemented using texture3D in OpenGL ES older than OpenGL ES 3.0,
    //       the shader might need "#extension GL_OES_texture_3D : enable".

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

    // Unpremultiply color
    fragBuilder->codeAppendf("\tfloat %s = max(%s.a, 0.00001);\n", nonZeroAlpha, args.fInputColor);
    fragBuilder->codeAppendf("\tvec4 %s = vec4(%s.rgb / %s, %s);\n",
                             unPMColor, args.fInputColor, nonZeroAlpha, nonZeroAlpha);

    // Fit input color into the cube.
    fragBuilder->codeAppendf(
        "vec3 %s = vec3(%s.rg * vec2((%s - 1.0) * %s) + vec2(0.5 * %s), %s.b * (%s - 1.0));\n",
        cubeIdx, unPMColor, colorCubeSizeUni, colorCubeInvSizeUni, colorCubeInvSizeUni,
        unPMColor, colorCubeSizeUni);

    // Compute y coord for for texture fetches.
    fragBuilder->codeAppendf("vec2 %s = vec2(%s.r, (floor(%s.b) + %s.g) * %s);\n",
                             cCoords1, cubeIdx, cubeIdx, cubeIdx, colorCubeInvSizeUni);
    fragBuilder->codeAppendf("vec2 %s = vec2(%s.r, (ceil(%s.b) + %s.g) * %s);\n",
                             cCoords2, cubeIdx, cubeIdx, cubeIdx, colorCubeInvSizeUni);

    // Apply the cube.
    fragBuilder->codeAppendf("%s = vec4(mix(", args.fOutputColor);
    fragBuilder->appendTextureLookup(args.fSamplers[0], cCoords1);
    fragBuilder->codeAppend(".bgr, ");
    fragBuilder->appendTextureLookup(args.fSamplers[0], cCoords2);

    // Premultiply color by alpha. Note that the input alpha is not modified by this shader.
    fragBuilder->codeAppendf(".bgr, fract(%s.b)) * vec3(%s), %s.a);\n",
                             cubeIdx, nonZeroAlpha, args.fInputColor);
}

void GrCircleBlurFragmentProcessor::GLSLProcessor::emitCode(EmitArgs& args) {
    const char *dataName;

    // The data is formatted as:
    // x,y  - the center of the circle
    // z    - inner radius that should map to 0th entry in the texture.
    // w    - the inverse of the distance over which the texture is stretched.
    fDataUniform = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec4f_GrSLType,
                                                    kDefault_GrSLPrecision,
                                                    "data",
                                                    &dataName);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

    if (args.fInputColor) {
        fragBuilder->codeAppendf("vec4 src=%s;", args.fInputColor);
    } else {
        fragBuilder->codeAppendf("vec4 src=vec4(1);");
    }

    // We just want to compute "(length(vec) - %s.z + 0.5) * %s.w" but need to rearrange
    // for precision.
    fragBuilder->codeAppendf("vec2 vec = vec2( (sk_FragCoord.x - %s.x) * %s.w, "
                                              "(sk_FragCoord.y - %s.y) * %s.w );",
                             dataName, dataName, dataName, dataName);
    fragBuilder->codeAppendf("float dist = length(vec) + (0.5 - %s.z) * %s.w;",
                             dataName, dataName);

    fragBuilder->codeAppendf("float intensity = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "vec2(dist, 0.5)");
    fragBuilder->codeAppend(".a;");

    fragBuilder->codeAppendf("%s = src * intensity;\n", args.fOutputColor );
}

void GrGLAlphaThresholdFragmentProcessor::emitCode(EmitArgs& args) {
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fInnerThresholdVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kFloat_GrSLType, kDefault_GrSLPrecision,
                                                    "inner_threshold");
    fOuterThresholdVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kFloat_GrSLType, kDefault_GrSLPrecision,
                                                    "outer_threshold");

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
    SkString maskCoords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 1);

    fragBuilder->codeAppendf("vec2 coord = %s;", coords2D.c_str());
    fragBuilder->codeAppendf("vec2 mask_coord = %s;", maskCoords2D.c_str());
    fragBuilder->codeAppend("vec4 input_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "coord");
    fragBuilder->codeAppend(";");
    fragBuilder->codeAppend("vec4 mask_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[1], "mask_coord");
    fragBuilder->codeAppend(";");

    fragBuilder->codeAppendf("float inner_thresh = %s;",
                             uniformHandler->getUniformCStr(fInnerThresholdVar));
    fragBuilder->codeAppendf("float outer_thresh = %s;",
                             uniformHandler->getUniformCStr(fOuterThresholdVar));
    fragBuilder->codeAppend("float mask = mask_color.a;");

    fragBuilder->codeAppend("vec4 color = input_color;");
    fragBuilder->codeAppend("if (mask < 0.5) {"
                            "if (color.a > outer_thresh) {"
                            "float scale = outer_thresh / color.a;"
                            "color.rgb *= scale;"
                            "color.a = outer_thresh;"
                            "}"
                            "} else if (color.a < inner_thresh) {"
                            "float scale = inner_thresh / max(0.001, color.a);"
                            "color.rgb *= scale;"
                            "color.a = inner_thresh;"
                            "}");

    fragBuilder->codeAppendf("%s = %s;", args.fOutputColor,
                             (GrGLSLExpr4(args.fInputColor) * GrGLSLExpr4("color")).c_str());
}

void GrGLMagnifierEffect::emitCode(EmitArgs& args) {
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fOffsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                            kVec2f_GrSLType, kDefault_GrSLPrecision,
                                            "Offset");
    fInvZoomVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                             kVec2f_GrSLType, kDefault_GrSLPrecision,
                                             "InvZoom");
    fInvInsetVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                              kVec2f_GrSLType, kDefault_GrSLPrecision,
                                              "InvInset");
    fBoundsVar = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                            kVec4f_GrSLType, kDefault_GrSLPrecision,
                                            "Bounds");

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
    fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
    fragBuilder->codeAppendf("\t\tvec2 zoom_coord = %s + %s * %s;\n",
                             uniformHandler->getUniformCStr(fOffsetVar),
                             coords2D.c_str(),
                             uniformHandler->getUniformCStr(fInvZoomVar));
    const char* bounds = uniformHandler->getUniformCStr(fBoundsVar);
    fragBuilder->codeAppendf("\t\tvec2 delta = (coord - %s.xy) * %s.zw;\n", bounds, bounds);
    fragBuilder->codeAppendf("\t\tdelta = min(delta, vec2(1.0, 1.0) - delta);\n");
    fragBuilder->codeAppendf("\t\tdelta = delta * %s;\n",
                             uniformHandler->getUniformCStr(fInvInsetVar));

    fragBuilder->codeAppend("\t\tfloat weight = 0.0;\n");
    fragBuilder->codeAppend("\t\tif (delta.s < 2.0 && delta.t < 2.0) {\n");
    fragBuilder->codeAppend("\t\t\tdelta = vec2(2.0, 2.0) - delta;\n");
    fragBuilder->codeAppend("\t\t\tfloat dist = length(delta);\n");
    fragBuilder->codeAppend("\t\t\tdist = max(2.0 - dist, 0.0);\n");
    fragBuilder->codeAppend("\t\t\tweight = min(dist * dist, 1.0);\n");
    fragBuilder->codeAppend("\t\t} else {\n");
    fragBuilder->codeAppend("\t\t\tvec2 delta_squared = delta * delta;\n");
    fragBuilder->codeAppend("\t\t\tweight = min(min(delta_squared.x, delta_squared.y), 1.0);\n");
    fragBuilder->codeAppend("\t\t}\n");

    fragBuilder->codeAppend("\t\tvec2 mix_coord = mix(coord, zoom_coord, weight);\n");
    fragBuilder->codeAppend("\t\tvec4 output_color = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "mix_coord");
    fragBuilder->codeAppend(";\n");

    fragBuilder->codeAppendf("\t\t%s = output_color;", args.fOutputColor);
    SkString modulate;
    GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
    fragBuilder->codeAppend(modulate.c_str());
}

void GrGLCircleBlurFragmentProcessor::emitCode(EmitArgs& args) {

    const char *dataName;

    // The data is formatted as:
    // x,y  - the center of the circle
    // z    - the distance at which the intensity starts falling off (e.g., the start of the table)
    // w    - the inverse of the profile texture size
    fDataUniform = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec4f_GrSLType,
                                                    kDefault_GrSLPrecision,
                                                    "data",
                                                    &dataName);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    const char *fragmentPos = fragBuilder->fragmentPosition();

    if (args.fInputColor) {
        fragBuilder->codeAppendf("vec4 src=%s;", args.fInputColor);
    } else {
        fragBuilder->codeAppendf("vec4 src=vec4(1);");
    }

    // We just want to compute "length(vec) - %s.z + 0.5) * %s.w" but need to rearrange
    // for precision
    fragBuilder->codeAppendf("vec2 vec = vec2( (%s.x - %s.x) * %s.w , (%s.y - %s.y) * %s.w );",
                             fragmentPos, dataName, dataName,
                             fragmentPos, dataName, dataName);
    fragBuilder->codeAppendf("float dist = length(vec) + ( 0.5 - %s.z ) * %s.w;",
                             dataName, dataName);

    fragBuilder->codeAppendf("float intensity = ");
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "vec2(dist, 0.5)");
    fragBuilder->codeAppend(".a;");

    fragBuilder->codeAppendf("%s = src * intensity;\n", args.fOutputColor );
}

void GrGLMorphologyEffect::emitCode(EmitArgs& args) {
    const GrMorphologyEffect& me = args.fFp.cast<GrMorphologyEffect>();

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fPixelSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                               kFloat_GrSLType, kDefault_GrSLPrecision,
                                               "PixelSize");
    const char* pixelSizeInc = uniformHandler->getUniformCStr(fPixelSizeUni);
    fRangeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                           kVec2f_GrSLType, kDefault_GrSLPrecision,
                                           "Range");
    const char* range = uniformHandler->getUniformCStr(fRangeUni);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 0);
    const char* func;
    switch (me.type()) {
        case GrMorphologyEffect::kErode_MorphologyType:
            fragBuilder->codeAppendf("\t\t%s = vec4(1, 1, 1, 1);\n", args.fOutputColor);
            func = "min";
            break;
        case GrMorphologyEffect::kDilate_MorphologyType:
            fragBuilder->codeAppendf("\t\t%s = vec4(0, 0, 0, 0);\n", args.fOutputColor);
            func = "max";
            break;
        default:
            SkFAIL("Unexpected type");
            func = ""; // suppress warning
            break;
    }

    const char* dir;
    switch (me.direction()) {
        case Gr1DKernelEffect::kX_Direction:
            dir = "x";
            break;
        case Gr1DKernelEffect::kY_Direction:
            dir = "y";
            break;
        default:
            SkFAIL("Unknown filter direction.");
            dir = ""; // suppress warning
    }

    int width = GrMorphologyEffect::WidthFromRadius(me.radius());

    // vec2 coord = coord2D;
    fragBuilder->codeAppendf("\t\tvec2 coord = %s;\n", coords2D.c_str());
    // coord.x -= radius * pixelSize;
    fragBuilder->codeAppendf("\t\tcoord.%s -= %d.0 * %s; \n", dir, me.radius(), pixelSizeInc);
    if (me.useRange()) {
        // highBound = min(highBound, coord.x + (width-1) * pixelSize);
        fragBuilder->codeAppendf("\t\tfloat highBound = min(%s.y, coord.%s + %f * %s);",
                                 range, dir, float(width - 1), pixelSizeInc);
        // coord.x = max(lowBound, coord.x);
        fragBuilder->codeAppendf("\t\tcoord.%s = max(%s.x, coord.%s);", dir, range, dir);
    }
    fragBuilder->codeAppendf("\t\tfor (int i = 0; i < %d; i++) {\n", width);
    fragBuilder->codeAppendf("\t\t\t%s = %s(%s, ", args.fOutputColor, func, args.fOutputColor);
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], "coord");
    fragBuilder->codeAppend(");\n");
    // coord.x += pixelSize;
    fragBuilder->codeAppendf("\t\t\tcoord.%s += %s;\n", dir, pixelSizeInc);
    if (me.useRange()) {
        // coord.x = min(highBound, coord.x);
        fragBuilder->codeAppendf("\t\t\tcoord.%s = min(highBound, coord.%s);", dir, dir);
    }
    fragBuilder->codeAppend("\t\t}\n");
    SkString modulate;
    GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
    fragBuilder->codeAppend(modulate.c_str());
}

void GrGLDisplacementMapEffect::emitCode(EmitArgs& args) {
    const GrDisplacementMapEffect& displacementMap = args.fFp.cast<GrDisplacementMapEffect>();
    const GrTextureDomain& domain = displacementMap.domain();

    fScaleUni = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
                                                 kVec2f_GrSLType, kDefault_GrSLPrecision, "Scale");
    const char* scaleUni = args.fUniformHandler->getUniformCStr(fScaleUni);
    const char* dColor = "dColor";
    const char* cCoords = "cCoords";
    const char* nearZero = "1e-6"; // Since 6.10352e−5 is the smallest half float, use
                                   // a number smaller than that to approximate 0, but
                                   // leave room for 32-bit float GPU rounding errors.

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    fragBuilder->codeAppendf("\t\tvec4 %s = ", dColor);
    fragBuilder->appendTextureLookup(args.fTexSamplers[0], args.fCoords[0].c_str(),
                                   args.fCoords[0].getType());
    fragBuilder->codeAppend(";\n");

    // Unpremultiply the displacement
    fragBuilder->codeAppendf(
        "\t\t%s.rgb = (%s.a < %s) ? vec3(0.0) : clamp(%s.rgb / %s.a, 0.0, 1.0);",
        dColor, dColor, nearZero, dColor, dColor);
    SkString coords2D = fragBuilder->ensureFSCoords2D(args.fCoords, 1);
    fragBuilder->codeAppendf("\t\tvec2 %s = %s + %s*(%s.",
                             cCoords, coords2D.c_str(), scaleUni, dColor);

    switch (displacementMap.xChannelSelector()) {
      case SkDisplacementMapEffect::kR_ChannelSelectorType:
        fragBuilder->codeAppend("r");
        break;
      case SkDisplacementMapEffect::kG_ChannelSelectorType:
        fragBuilder->codeAppend("g");
        break;
      case SkDisplacementMapEffect::kB_ChannelSelectorType:
        fragBuilder->codeAppend("b");
        break;
      case SkDisplacementMapEffect::kA_ChannelSelectorType:
        fragBuilder->codeAppend("a");
        break;
      case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
      default:
        SkDEBUGFAIL("Unknown X channel selector");
    }

    switch (displacementMap.yChannelSelector()) {
      case SkDisplacementMapEffect::kR_ChannelSelectorType:
        fragBuilder->codeAppend("r");
        break;
      case SkDisplacementMapEffect::kG_ChannelSelectorType:
        fragBuilder->codeAppend("g");
        break;
      case SkDisplacementMapEffect::kB_ChannelSelectorType:
        fragBuilder->codeAppend("b");
        break;
      case SkDisplacementMapEffect::kA_ChannelSelectorType:
        fragBuilder->codeAppend("a");
        break;
      case SkDisplacementMapEffect::kUnknown_ChannelSelectorType:
      default:
        SkDEBUGFAIL("Unknown Y channel selector");
    }
    fragBuilder->codeAppend("-vec2(0.5));\t\t");

    fGLDomain.sampleTexture(fragBuilder,
                            args.fUniformHandler,
                            args.fGLSLCaps,
                            domain,
                            args.fOutputColor,
                            SkString(cCoords),
                            args.fTexSamplers[1]);
    fragBuilder->codeAppend(";\n");
}

void GrGLPerlinNoise::emitCode(EmitArgs& args) {
    const GrPerlinNoiseEffect& pne = args.fFp.cast<GrPerlinNoiseEffect>();

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    SkString vCoords = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);

    fBaseFrequencyUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                   kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                   "baseFrequency");
    const char* baseFrequencyUni = uniformHandler->getUniformCStr(fBaseFrequencyUni);

    const char* stitchDataUni = nullptr;
    if (pne.stitchTiles()) {
        fStitchDataUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                    "stitchData");
        stitchDataUni = uniformHandler->getUniformCStr(fStitchDataUni);
    }

    // There are 4 lines, so the center of each line is 1/8, 3/8, 5/8 and 7/8
    const char* chanCoordR  = "0.125";
    const char* chanCoordG  = "0.375";
    const char* chanCoordB  = "0.625";
    const char* chanCoordA  = "0.875";
    const char* chanCoord   = "chanCoord";
    const char* stitchData  = "stitchData";
    const char* ratio       = "ratio";
    const char* noiseVec    = "noiseVec";
    const char* noiseSmooth = "noiseSmooth";
    const char* floorVal    = "floorVal";
    const char* fractVal    = "fractVal";
    const char* uv          = "uv";
    const char* ab          = "ab";
    const char* latticeIdx  = "latticeIdx";
    const char* bcoords     = "bcoords";
    const char* lattice     = "lattice";
    const char* inc8bit     = "0.00390625";  // 1.0 / 256.0
    // This is the math to convert the two 16bit integer packed into rgba 8 bit input into a
    // [-1,1] vector and perform a dot product between that vector and the provided vector.
    const char* dotLattice  = "dot(((%s.ga + %s.rb * vec2(%s)) * vec2(2.0) - vec2(1.0)), %s);";

    // Add noise function
    static const GrGLSLShaderVar gPerlinNoiseArgs[] =  {
        GrGLSLShaderVar(chanCoord, kFloat_GrSLType),
        GrGLSLShaderVar(noiseVec, kVec2f_GrSLType)
    };

    static const GrGLSLShaderVar gPerlinNoiseStitchArgs[] =  {
        GrGLSLShaderVar(chanCoord, kFloat_GrSLType),
        GrGLSLShaderVar(noiseVec, kVec2f_GrSLType),
        GrGLSLShaderVar(stitchData, kVec2f_GrSLType)
    };

    SkString noiseCode;

    noiseCode.appendf("\tvec4 %s;\n", floorVal);
    noiseCode.appendf("\t%s.xy = floor(%s);\n", floorVal, noiseVec);
    noiseCode.appendf("\t%s.zw = %s.xy + vec2(1.0);\n", floorVal, floorVal);
    noiseCode.appendf("\tvec2 %s = fract(%s);\n", fractVal, noiseVec);

    // smooth curve : t * t * (3 - 2 * t)
    noiseCode.appendf("\n\tvec2 %s = %s * %s * (vec2(3.0) - vec2(2.0) * %s);",
        noiseSmooth, fractVal, fractVal, fractVal);

    // Adjust frequencies if we're stitching tiles
    if (pne.stitchTiles()) {
        noiseCode.appendf("\n\tif(%s.x >= %s.x) { %s.x -= %s.x; }",
                          floorVal, stitchData, floorVal, stitchData);
        noiseCode.appendf("\n\tif(%s.y >= %s.y) { %s.y -= %s.y; }",
                          floorVal, stitchData, floorVal, stitchData);
        noiseCode.appendf("\n\tif(%s.z >= %s.x) { %s.z -= %s.x; }",
                          floorVal, stitchData, floorVal, stitchData);
        noiseCode.appendf("\n\tif(%s.w >= %s.y) { %s.w -= %s.y; }",
                          floorVal, stitchData, floorVal, stitchData);
    }

    // Get texture coordinates and normalize
    noiseCode.appendf("\n\t%s = fract(floor(mod(%s, 256.0)) / vec4(256.0));\n",
                      floorVal, floorVal);

    // Get permutation for x
    {
        SkString xCoords("");
        xCoords.appendf("vec2(%s.x, 0.5)", floorVal);

        noiseCode.appendf("\n\tvec2 %s;\n\t%s.x = ", latticeIdx, latticeIdx);
        fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[0], xCoords.c_str(),
                                         kVec2f_GrSLType);
        noiseCode.append(".r;");
    }

    // Get permutation for x + 1
    {
        SkString xCoords("");
        xCoords.appendf("vec2(%s.z, 0.5)", floorVal);

        noiseCode.appendf("\n\t%s.y = ", latticeIdx);
        fragBuilder->appendTextureLookup(&noiseCode, args.fTexSamplers[0], xCoords.c_str(),
                                         kVec2f_GrSLType);
//.........这里部分代码省略.........

    void emitCode(EmitArgs& args) override {
        const GrConfigConversionEffect& cce = args.fFp.cast<GrConfigConversionEffect>();
        const GrSwizzle& swizzle = cce.swizzle();
        GrConfigConversionEffect::PMConversion pmConversion = cce.pmConversion();

        // Using highp for GLES here in order to avoid some precision issues on specific GPUs.
        GrGLSLShaderVar tmpVar("tmpColor", kVec4f_GrSLType, 0, kHigh_GrSLPrecision);
        SkString tmpDecl;
        tmpVar.appendDecl(args.fGLSLCaps, &tmpDecl);

        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;

        fragBuilder->codeAppendf("%s;", tmpDecl.c_str());

        fragBuilder->codeAppendf("%s = ", tmpVar.c_str());
        fragBuilder->appendTextureLookup(args.fTexSamplers[0], args.fCoords[0].c_str(),
                                       args.fCoords[0].getType());
        fragBuilder->codeAppend(";");

        if (GrConfigConversionEffect::kNone_PMConversion == pmConversion) {
            SkASSERT(GrSwizzle::RGBA() != swizzle);
            fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
                                     swizzle.c_str());
        } else {
            switch (pmConversion) {
                case GrConfigConversionEffect::kMulByAlpha_RoundUp_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = vec4(ceil(%s.rgb * %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());
                    break;
                case GrConfigConversionEffect::kMulByAlpha_RoundDown_PMConversion:
                    // Add a compensation(0.001) here to avoid the side effect of the floor operation.
                    // In Intel GPUs, the integer value converted from floor(%s.r * 255.0) / 255.0
                    // is less than the integer value converted from  %s.r by 1 when the %s.r is
                    // converted from the integer value 2^n, such as 1, 2, 4, 8, etc.
                    fragBuilder->codeAppendf(
                        "%s = vec4(floor(%s.rgb * %s.a * 255.0 + 0.001) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str());

                    break;
                case GrConfigConversionEffect::kDivByAlpha_RoundUp_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(ceil(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
                        tmpVar.c_str());
                    break;
                case GrConfigConversionEffect::kDivByAlpha_RoundDown_PMConversion:
                    fragBuilder->codeAppendf(
                        "%s = %s.a <= 0.0 ? vec4(0,0,0,0) : vec4(floor(%s.rgb / %s.a * 255.0) / 255.0, %s.a);",
                        tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(), tmpVar.c_str(),
                        tmpVar.c_str());
                    break;
                default:
                    SkFAIL("Unknown conversion op.");
                    break;
            }
            fragBuilder->codeAppendf("%s = %s.%s;", args.fOutputColor, tmpVar.c_str(),
                                     swizzle.c_str());
        }
        SkString modulate;
        GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
        fragBuilder->codeAppend(modulate.c_str());
    }

void GrGLConvolutionEffect::emitCode(EmitArgs& args) {
    const GrConvolutionEffect& ce = args.fFp.cast<GrConvolutionEffect>();

    GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
    fImageIncrementUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                    kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                    "ImageIncrement");
    if (ce.useBounds()) {
        fBoundsUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
                                                kVec2f_GrSLType, kDefault_GrSLPrecision,
                                                "Bounds");
    }

    int width = Gr1DKernelEffect::WidthFromRadius(ce.radius());

    int arrayCount = (width + 3) / 4;
    SkASSERT(4 * arrayCount >= width);

    fKernelUni = uniformHandler->addUniformArray(kFragment_GrShaderFlag,
                                                 kVec4f_GrSLType, kDefault_GrSLPrecision,
                                                 "Kernel", arrayCount);

    GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
    SkString coords2D = fragBuilder->ensureCoords2D(args.fTransformedCoords[0]);

    fragBuilder->codeAppendf("%s = vec4(0, 0, 0, 0);", args.fOutputColor);

    const GrGLSLShaderVar& kernel = uniformHandler->getUniformVariable(fKernelUni);
    const char* imgInc = uniformHandler->getUniformCStr(fImageIncrementUni);

    fragBuilder->codeAppendf("vec2 coord = %s - %d.0 * %s;", coords2D.c_str(), ce.radius(), imgInc);

    // Manually unroll loop because some drivers don't; yields 20-30% speedup.
    const char* kVecSuffix[4] = { ".x", ".y", ".z", ".w" };
    for (int i = 0; i < width; i++) {
        SkString index;
        SkString kernelIndex;
        index.appendS32(i/4);
        kernel.appendArrayAccess(index.c_str(), &kernelIndex);
        kernelIndex.append(kVecSuffix[i & 0x3]);

        if (ce.useBounds()) {
            // We used to compute a bool indicating whether we're in bounds or not, cast it to a
            // float, and then mul weight*texture_sample by the float. However, the Adreno 430 seems
            // to have a bug that caused corruption.
            const char* bounds = uniformHandler->getUniformCStr(fBoundsUni);
            const char* component = ce.direction() == Gr1DKernelEffect::kY_Direction ? "y" : "x";
            fragBuilder->codeAppendf("if (coord.%s >= %s.x && coord.%s <= %s.y) {",
                                     component, bounds, component, bounds);
        }
        fragBuilder->codeAppendf("\t\t%s += ", args.fOutputColor);
        fragBuilder->appendTextureLookup(args.fTexSamplers[0], "coord");
        fragBuilder->codeAppendf(" * %s;\n", kernelIndex.c_str());
        if (ce.useBounds()) {
            fragBuilder->codeAppend("}");
        }
        fragBuilder->codeAppendf("\t\tcoord += %s;\n", imgInc);
    }

    SkString modulate;
    GrGLSLMulVarBy4f(&modulate, args.fOutputColor, args.fInputColor);
    fragBuilder->codeAppend(modulate.c_str());
}