diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/src/gpu/effects/GrBicubicEffect.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/skia/trunk/src/gpu/effects/GrBicubicEffect.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,179 @@
+#include "GrBicubicEffect.h"
+
+#define DS(x) SkDoubleToScalar(x)
+
+const SkScalar GrBicubicEffect::gMitchellCoefficients[16] = {
+    DS( 1.0 / 18.0), DS(-9.0 / 18.0), DS( 15.0 / 18.0), DS( -7.0 / 18.0),
+    DS(16.0 / 18.0), DS( 0.0 / 18.0), DS(-36.0 / 18.0), DS( 21.0 / 18.0),
+    DS( 1.0 / 18.0), DS( 9.0 / 18.0), DS( 27.0 / 18.0), DS(-21.0 / 18.0),
+    DS( 0.0 / 18.0), DS( 0.0 / 18.0), DS( -6.0 / 18.0), DS(  7.0 / 18.0),
+};
+
+
+class GrGLBicubicEffect : public GrGLEffect {
+public:
+    GrGLBicubicEffect(const GrBackendEffectFactory& factory,
+                      const GrDrawEffect&);
+
+    virtual void emitCode(GrGLShaderBuilder*,
+                          const GrDrawEffect&,
+                          EffectKey,
+                          const char* outputColor,
+                          const char* inputColor,
+                          const TransformedCoordsArray&,
+                          const TextureSamplerArray&) SK_OVERRIDE;
+
+    virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
+
+    static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
+        const GrTextureDomain& domain = drawEffect.castEffect<GrBicubicEffect>().domain();
+        return GrTextureDomain::GLDomain::DomainKey(domain);
+    }
+
+private:
+    typedef GrGLUniformManager::UniformHandle        UniformHandle;
+
+    UniformHandle               fCoefficientsUni;
+    UniformHandle               fImageIncrementUni;
+    GrTextureDomain::GLDomain   fDomain;
+
+    typedef GrGLEffect INHERITED;
+};
+
+GrGLBicubicEffect::GrGLBicubicEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
+    : INHERITED(factory) {
+}
+
+void GrGLBicubicEffect::emitCode(GrGLShaderBuilder* builder,
+                                 const GrDrawEffect& drawEffect,
+                                 EffectKey key,
+                                 const char* outputColor,
+                                 const char* inputColor,
+                                 const TransformedCoordsArray& coords,
+                                 const TextureSamplerArray& samplers) {
+    const GrTextureDomain& domain = drawEffect.castEffect<GrBicubicEffect>().domain();
+
+    SkString coords2D = builder->ensureFSCoords2D(coords, 0);
+    fCoefficientsUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+                                           kMat44f_GrSLType, "Coefficients");
+    fImageIncrementUni = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+                                             kVec2f_GrSLType, "ImageIncrement");
+
+    const char* imgInc = builder->getUniformCStr(fImageIncrementUni);
+    const char* coeff = builder->getUniformCStr(fCoefficientsUni);
+
+    SkString cubicBlendName;
+
+    static const GrGLShaderVar gCubicBlendArgs[] = {
+        GrGLShaderVar("coefficients",  kMat44f_GrSLType),
+        GrGLShaderVar("t",             kFloat_GrSLType),
+        GrGLShaderVar("c0",            kVec4f_GrSLType),
+        GrGLShaderVar("c1",            kVec4f_GrSLType),
+        GrGLShaderVar("c2",            kVec4f_GrSLType),
+        GrGLShaderVar("c3",            kVec4f_GrSLType),
+    };
+    builder->fsEmitFunction(kVec4f_GrSLType,
+                            "cubicBlend",
+                            SK_ARRAY_COUNT(gCubicBlendArgs),
+                            gCubicBlendArgs,
+                            "\tvec4 ts = vec4(1.0, t, t * t, t * t * t);\n"
+                            "\tvec4 c = coefficients * ts;\n"
+                            "\treturn c.x * c0 + c.y * c1 + c.z * c2 + c.w * c3;\n",
+                            &cubicBlendName);
+    builder->fsCodeAppendf("\tvec2 coord = %s - %s * vec2(0.5);\n", coords2D.c_str(), imgInc);
+    // We unnormalize the coord in order to determine our fractional offset (f) within the texel
+    // We then snap coord to a texel center and renormalize. The snap prevents cases where the
+    // starting coords are near a texel boundary and accumulations of imgInc would cause us to skip/
+    // double hit a texel.
+    builder->fsCodeAppendf("\tcoord /= %s;\n", imgInc);
+    builder->fsCodeAppend("\tvec2 f = fract(coord);\n");
+    builder->fsCodeAppendf("\tcoord = (coord - f + vec2(0.5)) * %s;\n", imgInc);
+    builder->fsCodeAppend("\tvec4 rowColors[4];\n");
+    for (int y = 0; y < 4; ++y) {
+        for (int x = 0; x < 4; ++x) {
+            SkString coord;
+            coord.printf("coord + %s * vec2(%d, %d)", imgInc, x - 1, y - 1);
+            SkString sampleVar;
+            sampleVar.printf("rowColors[%d]", x);
+            fDomain.sampleTexture(builder, domain, sampleVar.c_str(), coord, samplers[0]);
+        }
+        builder->fsCodeAppendf("\tvec4 s%d = %s(%s, f.x, rowColors[0], rowColors[1], rowColors[2], rowColors[3]);\n", y, cubicBlendName.c_str(), coeff);
+    }
+    SkString bicubicColor;
+    bicubicColor.printf("%s(%s, f.y, s0, s1, s2, s3)", cubicBlendName.c_str(), coeff);
+    builder->fsCodeAppendf("\t%s = %s;\n", outputColor, (GrGLSLExpr4(bicubicColor.c_str()) * GrGLSLExpr4(inputColor)).c_str());
+}
+
+void GrGLBicubicEffect::setData(const GrGLUniformManager& uman,
+                                const GrDrawEffect& drawEffect) {
+    const GrBicubicEffect& effect = drawEffect.castEffect<GrBicubicEffect>();
+    const GrTexture& texture = *effect.texture(0);
+    float imageIncrement[2];
+    imageIncrement[0] = 1.0f / texture.width();
+    imageIncrement[1] = 1.0f / texture.height();
+    uman.set2fv(fImageIncrementUni, 1, imageIncrement);
+    uman.setMatrix4f(fCoefficientsUni, effect.coefficients());
+    fDomain.setData(uman, effect.domain(), texture.origin());
+}
+
+static inline void convert_row_major_scalar_coeffs_to_column_major_floats(float dst[16],
+                                                                          const SkScalar src[16]) {
+    for (int y = 0; y < 4; y++) {
+        for (int x = 0; x < 4; x++) {
+            dst[x * 4 + y] = SkScalarToFloat(src[y * 4 + x]);
+        }
+    }
+}
+
+GrBicubicEffect::GrBicubicEffect(GrTexture* texture,
+                                 const SkScalar coefficients[16],
+                                 const SkMatrix &matrix,
+                                 const SkShader::TileMode tileModes[2])
+  : INHERITED(texture, matrix, GrTextureParams(tileModes, GrTextureParams::kNone_FilterMode))
+  , fDomain(GrTextureDomain::IgnoredDomain()) {
+    convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients);
+}
+
+GrBicubicEffect::GrBicubicEffect(GrTexture* texture,
+                                 const SkScalar coefficients[16],
+                                 const SkMatrix &matrix,
+                                 const SkRect& domain)
+  : INHERITED(texture, matrix, GrTextureParams(SkShader::kClamp_TileMode,
+                                               GrTextureParams::kNone_FilterMode))
+  , fDomain(domain, GrTextureDomain::kClamp_Mode) {
+    convert_row_major_scalar_coeffs_to_column_major_floats(fCoefficients, coefficients);
+}
+
+GrBicubicEffect::~GrBicubicEffect() {
+}
+
+const GrBackendEffectFactory& GrBicubicEffect::getFactory() const {
+    return GrTBackendEffectFactory<GrBicubicEffect>::getInstance();
+}
+
+bool GrBicubicEffect::onIsEqual(const GrEffect& sBase) const {
+    const GrBicubicEffect& s = CastEffect<GrBicubicEffect>(sBase);
+    return this->textureAccess(0) == s.textureAccess(0) &&
+           !memcmp(fCoefficients, s.coefficients(), 16);
+}
+
+void GrBicubicEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
+    // FIXME: Perhaps we can do better.
+    *validFlags = 0;
+    return;
+}
+
+GR_DEFINE_EFFECT_TEST(GrBicubicEffect);
+
+GrEffectRef* GrBicubicEffect::TestCreate(SkRandom* random,
+                                         GrContext* context,
+                                         const GrDrawTargetCaps&,
+                                         GrTexture* textures[]) {
+    int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
+                                      GrEffectUnitTest::kAlphaTextureIdx;
+    SkScalar coefficients[16];
+    for (int i = 0; i < 16; i++) {
+        coefficients[i] = random->nextSScalar1();
+    }
+    return GrBicubicEffect::Create(textures[texIdx], coefficients);
+}