Emulate gamma fix by making glyphs thicker or thinner

src/gpu/effects/GrDistanceFieldTextureEffect.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDistanceFieldTextureEffect.h"
 #include "GrFontAtlasSizes.h"
 #include "GrInvariantOutput.h"
 #include "GrTexture.h"
+
 #include "SkDistanceFieldGen.h"
+
 #include "gl/GrGLProcessor.h"
 #include "gl/GrGLSL.h"
 #include "gl/GrGLTexture.h"
 #include "gl/GrGLGeometryProcessor.h"
 #include "gl/builders/GrGLProgramBuilder.h"
 
 // Assuming a radius of the diagonal of the fragment, hence a factor of sqrt(2)/2
 #define SK_DistanceFieldAAFactor     "0.65"
 
 struct DistanceFieldBatchTracker {
     GrGPInput fInputColorType;
     GrColor fColor;
     bool fUsesLocalCoords;
 };
 
 class GrGLDistanceFieldTextureEffect : public GrGLGeometryProcessor {
 public:
     GrGLDistanceFieldTextureEffect(const GrGeometryProcessor&,
                                    const GrBatchTracker&)
         : fColor(GrColor_ILLEGAL)
 #ifdef SK_GAMMA_APPLY_TO_A8
-        , fLuminance(-1.0f)
+        , fWidthAdjust(-1.0f)
 #endif
         {}
 
     void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
         const GrDistanceFieldTextureEffect& dfTexEffect =
                 args.fGP.cast<GrDistanceFieldTextureEffect>();
         const DistanceFieldBatchTracker& local = args.fBT.cast<DistanceFieldBatchTracker>();
         GrGLGPBuilder* pb = args.fPB;
         GrGLGPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
         SkAssertResult(fsBuilder->enableFeature(
                 GrGLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
 
         GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
 
         // emit attributes
         vsBuilder->emitAttributes(dfTexEffect);
 
         GrGLVertToFrag st(kVec2f_GrSLType);
         args.fPB->addVarying("IntTextureCoords", &st, kHigh_GrSLPrecision);
         vsBuilder->codeAppendf("%s = %s;", st.vsOut(), dfTexEffect.inTextureCoords()->fName);
         
         GrGLVertToFrag uv(kVec2f_GrSLType);
         args.fPB->addVarying("TextureCoords", &uv, kHigh_GrSLPrecision);
         // this is only used with text, so our texture bounds always match the glyph atlas
         vsBuilder->codeAppendf("%s = vec2(" GR_FONT_ATLAS_A8_RECIP_WIDTH ", "
                                GR_FONT_ATLAS_RECIP_HEIGHT ")*%s;", uv.vsOut(),
                                dfTexEffect.inTextureCoords()->fName);
+#ifdef SK_GAMMA_APPLY_TO_A8
+        // adjust based on gamma
+        const char* widthAdjustUniName = NULL;
+        // width, height, 1/(3*width)
+        fWidthAdjustUni = args.fPB->addUniform(GrGLProgramBuilder::kFragment_Visibility,
+            kFloat_GrSLType, kDefault_GrSLPrecision,
+            "WidthAdjust", &widthAdjustUniName);
+#endif
 
         // Setup pass through color
         this->setupColorPassThrough(pb, local.fInputColorType, args.fOutputColor,
                                     dfTexEffect.inColor(), &fColorUniform);
 
         // Setup position
         this->setupPosition(pb, gpArgs, dfTexEffect.inPosition()->fName, dfTexEffect.viewMatrix());
 
         // emit transforms
         this->emitTransforms(args.fPB, gpArgs->fPositionVar, dfTexEffect.inPosition()->fName,
                              dfTexEffect.localMatrix(), args.fTransformsIn, args.fTransformsOut);
 
         // Use highp to work around aliasing issues
         fsBuilder->codeAppend(GrGLShaderVar::PrecisionString(kHigh_GrSLPrecision,
                                                              pb->ctxInfo().standard()));
         fsBuilder->codeAppendf("vec2 uv = %s;\n", uv.fsIn());
 
         fsBuilder->codeAppend("\tfloat texColor = ");
         fsBuilder->appendTextureLookup(args.fSamplers[0],
                                        "uv",
                                        kVec2f_GrSLType);
         fsBuilder->codeAppend(".r;\n");
         fsBuilder->codeAppend("\tfloat distance = "
                        SK_DistanceFieldMultiplier "*(texColor - " SK_DistanceFieldThreshold ");");
+#ifdef SK_GAMMA_APPLY_TO_A8
+        // adjust width based on gamma
+        fsBuilder->codeAppendf("distance -= %s;", widthAdjustUniName);
+#endif
 
         fsBuilder->codeAppend(GrGLShaderVar::PrecisionString(kHigh_GrSLPrecision,
                                                              pb->ctxInfo().standard()));
         fsBuilder->codeAppendf("vec2 st = %s;", st.fsIn());
         fsBuilder->codeAppend("float afwidth;");
         if (dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag) {
             // For uniform scale, we adjust for the effect of the transformation on the distance
             // by using the length of the gradient of the texture coordinates. We use st coordinates
             // to ensure we're mapping 1:1 from texel space to pixel space.
 
@@ skipping 16 matching lines @@
             fsBuilder->codeAppend("vec2 Jdx = dFdx(st);");
             fsBuilder->codeAppend("vec2 Jdy = dFdy(st);");
             fsBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
             fsBuilder->codeAppend("                 dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
 
             // this gives us a smooth step across approximately one fragment
             fsBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
         }
         fsBuilder->codeAppend("float val = smoothstep(-afwidth, afwidth, distance);");
 
-#ifdef SK_GAMMA_APPLY_TO_A8
-        // adjust based on gamma
-        const char* luminanceUniName = NULL;
-        // width, height, 1/(3*width)
-        fLuminanceUni = args.fPB->addUniform(GrGLProgramBuilder::kFragment_Visibility,
-                                             kFloat_GrSLType, kDefault_GrSLPrecision,
-                                             "Luminance", &luminanceUniName);
-
-        fsBuilder->codeAppendf("\tuv = vec2(val, %s);\n", luminanceUniName);
-        fsBuilder->codeAppend("\tvec4 gammaColor = ");
-        fsBuilder->appendTextureLookup(args.fSamplers[1], "uv", kVec2f_GrSLType);
-        fsBuilder->codeAppend(";\n");
-        fsBuilder->codeAppend("\tval = gammaColor.r;\n");
-#endif
-
         fsBuilder->codeAppendf("%s = vec4(val);", args.fOutputCoverage);
     }
 
     virtual void setData(const GrGLProgramDataManager& pdman,
                          const GrPrimitiveProcessor& proc,
                          const GrBatchTracker& bt) override {
 #ifdef SK_GAMMA_APPLY_TO_A8
         const GrDistanceFieldTextureEffect& dfTexEffect =
                 proc.cast<GrDistanceFieldTextureEffect>();
-        float luminance = dfTexEffect.getLuminance();
-        if (luminance != fLuminance) {
-            pdman.set1f(fLuminanceUni, luminance);
-            fLuminance = luminance;
+        float widthAdjust = dfTexEffect.getWidthAdjust();
+        if (widthAdjust != fWidthAdjust) {
+            pdman.set1f(fWidthAdjustUni, widthAdjust);
+            fWidthAdjust = widthAdjust;
         }
 #endif
 
         this->setUniformViewMatrix(pdman, proc.viewMatrix());
 
         const DistanceFieldBatchTracker& local = bt.cast<DistanceFieldBatchTracker>();
         if (kUniform_GrGPInput == local.fInputColorType && local.fColor != fColor) {
             GrGLfloat c[4];
             GrColorToRGBAFloat(local.fColor, c);
             pdman.set4fv(fColorUniform, 1, c);
@@ skipping 11 matching lines @@
         key |= local.fInputColorType << 16;
         key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x1 << 24: 0x0;
         key |= ComputePosKey(gp.viewMatrix()) << 25;
         b->add32(key);
     }
 
 private:
     GrColor       fColor;
     UniformHandle fColorUniform;
 #ifdef SK_GAMMA_APPLY_TO_A8
-    UniformHandle fLuminanceUni;
-    float         fLuminance;
+    float         fWidthAdjust;
+    UniformHandle fWidthAdjustUni;
 #endif
 
     typedef GrGLGeometryProcessor INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GrDistanceFieldTextureEffect::GrDistanceFieldTextureEffect(GrColor color,
                                                            const SkMatrix& viewMatrix,
                                                            GrTexture* texture,
                                                            const GrTextureParams& params,
 #ifdef SK_GAMMA_APPLY_TO_A8
-                                                           GrTexture* gamma,
-                                                           const GrTextureParams& gammaParams,
-                                                           float luminance,
+                                                           float widthAdjust,
 #endif
                                                            uint32_t flags, bool opaqueVertexColors)
     : INHERITED(color, viewMatrix, SkMatrix::I(), opaqueVertexColors)
     , fTextureAccess(texture, params)
 #ifdef SK_GAMMA_APPLY_TO_A8
-    , fGammaTextureAccess(gamma, gammaParams)
-    , fLuminance(luminance)
+    , fWidthAdjust(widthAdjust)
 #endif
     , fFlags(flags & kNonLCD_DistanceFieldEffectMask)
     , fInColor(NULL) {
     SkASSERT(!(flags & ~kNonLCD_DistanceFieldEffectMask));
     this->initClassID<GrDistanceFieldTextureEffect>();
     fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType));
     if (flags & kColorAttr_DistanceFieldEffectFlag) {
         fInColor = &this->addVertexAttrib(Attribute("inColor", kVec4ub_GrVertexAttribType));
         this->setHasVertexColor();
     }
     fInTextureCoords = &this->addVertexAttrib(Attribute("inTextureCoords",
                                                           kVec2s_GrVertexAttribType));
     this->addTextureAccess(&fTextureAccess);
-#ifdef SK_GAMMA_APPLY_TO_A8
-    this->addTextureAccess(&fGammaTextureAccess);
-#endif
 }
 
 bool GrDistanceFieldTextureEffect::onIsEqual(const GrGeometryProcessor& other) const {
     const GrDistanceFieldTextureEffect& cte = other.cast<GrDistanceFieldTextureEffect>();
     return
 #ifdef SK_GAMMA_APPLY_TO_A8
-           fLuminance == cte.fLuminance &&
+           fWidthAdjust == cte.fWidthAdjust &&
 #endif
            fFlags == cte.fFlags;
 }
 
 void GrDistanceFieldTextureEffect::onGetInvariantOutputCoverage(GrInitInvariantOutput* out) const {
     out->setUnknownSingleComponent();
 }
 
 void GrDistanceFieldTextureEffect::getGLProcessorKey(const GrBatchTracker& bt,
                                                      const GrGLCaps& caps,
@@ skipping 28 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldTextureEffect);
 
 GrGeometryProcessor* GrDistanceFieldTextureEffect::TestCreate(SkRandom* random,
                                                               GrContext*,
                                                               const GrDrawTargetCaps&,
                                                               GrTexture* textures[]) {
     int texIdx = random->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx :
                                       GrProcessorUnitTest::kAlphaTextureIdx;
-#ifdef SK_GAMMA_APPLY_TO_A8
-    int texIdx2 = random->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx :
-                                       GrProcessorUnitTest::kAlphaTextureIdx;
-#endif
     static const SkShader::TileMode kTileModes[] = {
         SkShader::kClamp_TileMode,
         SkShader::kRepeat_TileMode,
         SkShader::kMirror_TileMode,
     };
     SkShader::TileMode tileModes[] = {
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
     };
     GrTextureParams params(tileModes, random->nextBool() ? GrTextureParams::kBilerp_FilterMode :
                                                            GrTextureParams::kNone_FilterMode);
-#ifdef SK_GAMMA_APPLY_TO_A8
-    GrTextureParams params2(tileModes, random->nextBool() ? GrTextureParams::kBilerp_FilterMode :
-                                                            GrTextureParams::kNone_FilterMode);
-#endif
 
     return GrDistanceFieldTextureEffect::Create(GrRandomColor(random),
                                                 GrProcessorUnitTest::TestMatrix(random),
                                                 textures[texIdx], params,
 #ifdef SK_GAMMA_APPLY_TO_A8
-                                                textures[texIdx2], params2,
                                                 random->nextF(),
 #endif
                                                 random->nextBool() ?
                                                     kSimilarity_DistanceFieldEffectFlag : 0,
                                                 random->nextBool());
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 struct DistanceFieldNoGammaBatchTracker {
@@ skipping 245 matching lines @@
 struct DistanceFieldLCDBatchTracker {
     GrGPInput fInputColorType;
     GrColor fColor;
     bool fUsesLocalCoords;
 };
 
 class GrGLDistanceFieldLCDTextureEffect : public GrGLGeometryProcessor {
 public:
     GrGLDistanceFieldLCDTextureEffect(const GrGeometryProcessor&,
                                       const GrBatchTracker&)
-    : fColor(GrColor_ILLEGAL)
-    , fTextColor(GrColor_ILLEGAL) {}
+        : fColor(GrColor_ILLEGAL) {
+        fWidthAdjust = GrDistanceFieldLCDTextureEffect::WidthAdjust::Make(1.0f, 1.0f, 1.0f);
+    }
 
     void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
         const GrDistanceFieldLCDTextureEffect& dfTexEffect =
                 args.fGP.cast<GrDistanceFieldLCDTextureEffect>();
         const DistanceFieldLCDBatchTracker& local = args.fBT.cast<DistanceFieldLCDBatchTracker>();
         GrGLGPBuilder* pb = args.fPB;
 
         GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
 
         // emit attributes
@@ skipping 65 matching lines @@
         // blue is distance to right offset
         fsBuilder->codeAppend("\tuv_adjusted = uv + offset;\n");
         fsBuilder->codeAppend("\ttexColor = ");
         fsBuilder->appendTextureLookup(args.fSamplers[0], "uv_adjusted", kVec2f_GrSLType);
         fsBuilder->codeAppend(";\n");
         fsBuilder->codeAppend("\tdistance.z = texColor.r;\n");
 
         fsBuilder->codeAppend("\tdistance = "
            "vec3(" SK_DistanceFieldMultiplier ")*(distance - vec3(" SK_DistanceFieldThreshold"));");
 
+        // adjust width based on gamma
+        const char* widthAdjustUniName = NULL;
+        fWidthAdjustUni = args.fPB->addUniform(GrGLProgramBuilder::kFragment_Visibility,
+            kVec3f_GrSLType, kDefault_GrSLPrecision,
+            "WidthAdjust", &widthAdjustUniName);
+        fsBuilder->codeAppendf("distance -= %s;", widthAdjustUniName);
+
         // To be strictly correct, we should compute the anti-aliasing factor separately
         // for each color component. However, this is only important when using perspective
         // transformations, and even then using a single factor seems like a reasonable
         // trade-off between quality and speed.
         fsBuilder->codeAppend("float afwidth;");
         if (isUniformScale) {
             // For uniform scale, we adjust for the effect of the transformation on the distance
             // by using the length of the gradient of the texture coordinates. We use st coordinates
             // to ensure we're mapping 1:1 from texel space to pixel space.
 
@@ skipping 14 matching lines @@
             fsBuilder->codeAppend("}");
             fsBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
             fsBuilder->codeAppend("                 dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
 
             // this gives us a smooth step across approximately one fragment
             fsBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
         }
 
         fsBuilder->codeAppend("vec4 val = vec4(smoothstep(vec3(-afwidth), vec3(afwidth), distance), 1.0);");
 
-        // adjust based on gamma
-        const char* textColorUniName = NULL;
-        fTextColorUni = args.fPB->addUniform(GrGLProgramBuilder::kFragment_Visibility,
-                                             kVec3f_GrSLType, kDefault_GrSLPrecision,
-                                             "TextColor", &textColorUniName);
-
-        fsBuilder->codeAppendf("\tuv = vec2(val.x, %s.x);\n", textColorUniName);
-        fsBuilder->codeAppend("float gammaColor = ");
-        fsBuilder->appendTextureLookup(args.fSamplers[1], "uv", kVec2f_GrSLType);
-        fsBuilder->codeAppend(".r;\n");
-        fsBuilder->codeAppend("\tval.x = gammaColor;\n");
-
-        fsBuilder->codeAppendf("\tuv = vec2(val.y, %s.y);\n", textColorUniName);
-        fsBuilder->codeAppend("\tgammaColor = ");
-        fsBuilder->appendTextureLookup(args.fSamplers[1], "uv", kVec2f_GrSLType);
-        fsBuilder->codeAppend(".r;\n");
-        fsBuilder->codeAppend("\tval.y = gammaColor;\n");
-
-        fsBuilder->codeAppendf("\tuv = vec2(val.z, %s.z);\n", textColorUniName);
-        fsBuilder->codeAppend("\tgammaColor = ");
-        fsBuilder->appendTextureLookup(args.fSamplers[1], "uv", kVec2f_GrSLType);
-        fsBuilder->codeAppend(".r;\n");
-        fsBuilder->codeAppend("\tval.z = gammaColor;\n");
-
         fsBuilder->codeAppendf("%s = vec4(val);", args.fOutputCoverage);
     }
 
     virtual void setData(const GrGLProgramDataManager& pdman,
                          const GrPrimitiveProcessor& processor,
                          const GrBatchTracker& bt) override {
-        SkASSERT(fTextColorUni.isValid());
+        SkASSERT(fWidthAdjustUni.isValid());
 
         const GrDistanceFieldLCDTextureEffect& dfTexEffect =
                 processor.cast<GrDistanceFieldLCDTextureEffect>();
-        GrColor textColor = dfTexEffect.getTextColor();
-        if (textColor != fTextColor) {
-            static const float ONE_OVER_255 = 1.f / 255.f;
-            pdman.set3f(fTextColorUni,
-                        GrColorUnpackR(textColor) * ONE_OVER_255,
-                        GrColorUnpackG(textColor) * ONE_OVER_255,
-                        GrColorUnpackB(textColor) * ONE_OVER_255);
-            fTextColor = textColor;
+        GrDistanceFieldLCDTextureEffect::WidthAdjust wa = dfTexEffect.getWidthAdjust();
+        if (wa != fWidthAdjust) {
+            pdman.set3f(fWidthAdjustUni,
+                        wa.fR,
+                        wa.fG,
+                        wa.fB);
+            fWidthAdjust = wa;
         }
 
         this->setUniformViewMatrix(pdman, processor.viewMatrix());
 
         const DistanceFieldLCDBatchTracker& local = bt.cast<DistanceFieldLCDBatchTracker>();
         if (kUniform_GrGPInput == local.fInputColorType && local.fColor != fColor) {
             GrGLfloat c[4];
             GrColorToRGBAFloat(local.fColor, c);
             pdman.set4fv(fColorUniform, 1, c);
             fColor = local.fColor;
         }
     }
 
     static inline void GenKey(const GrGeometryProcessor& gp,
                               const GrBatchTracker& bt,
                               const GrGLCaps&,
                               GrProcessorKeyBuilder* b) {
         const GrDistanceFieldLCDTextureEffect& dfTexEffect =
                 gp.cast<GrDistanceFieldLCDTextureEffect>();
 
         const DistanceFieldLCDBatchTracker& local = bt.cast<DistanceFieldLCDBatchTracker>();
         uint32_t key = dfTexEffect.getFlags();
         key |= local.fInputColorType << 16;
         key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x1 << 24: 0x0;
         key |= ComputePosKey(gp.viewMatrix()) << 25;
         b->add32(key);
     }
 
 private:
-    GrColor       fColor;
-    UniformHandle fColorUniform;
-    UniformHandle fTextColorUni;
-    SkColor       fTextColor;
+    GrColor                                      fColor;
+    UniformHandle                                fColorUniform;
+    GrDistanceFieldLCDTextureEffect::WidthAdjust fWidthAdjust;
+    UniformHandle                                fWidthAdjustUni;
 
     typedef GrGLGeometryProcessor INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 GrDistanceFieldLCDTextureEffect::GrDistanceFieldLCDTextureEffect(
                                                   GrColor color, const SkMatrix& viewMatrix,
                                                   GrTexture* texture, const GrTextureParams& params,
-                                                  GrTexture* gamma, const GrTextureParams& gParams,
-                                                  SkColor textColor,
+                                                  WidthAdjust widthAdjust,
                                                   uint32_t flags)
     : INHERITED(color, viewMatrix, SkMatrix::I())
     , fTextureAccess(texture, params)
-    , fGammaTextureAccess(gamma, gParams)
-    , fTextColor(textColor)
+    , fWidthAdjust(widthAdjust)
     , fFlags(flags & kLCD_DistanceFieldEffectMask){
     SkASSERT(!(flags & ~kLCD_DistanceFieldEffectMask) && (flags & kUseLCD_DistanceFieldEffectFlag));
     this->initClassID<GrDistanceFieldLCDTextureEffect>();
     fInPosition = &this->addVertexAttrib(Attribute("inPosition", kVec2f_GrVertexAttribType));
     fInTextureCoords = &this->addVertexAttrib(Attribute("inTextureCoords",
                                                           kVec2s_GrVertexAttribType));
     this->addTextureAccess(&fTextureAccess);
-    this->addTextureAccess(&fGammaTextureAccess);
 }
 
 bool GrDistanceFieldLCDTextureEffect::onIsEqual(const GrGeometryProcessor& other) const {
     const GrDistanceFieldLCDTextureEffect& cte = other.cast<GrDistanceFieldLCDTextureEffect>();
-    return (fTextColor == cte.fTextColor &&
+    return (fWidthAdjust == cte.fWidthAdjust &&
             fFlags == cte.fFlags);
 }
 
 void GrDistanceFieldLCDTextureEffect::onGetInvariantOutputCoverage(GrInitInvariantOutput* out) const {
     out->setUnknownFourComponents();
     out->setUsingLCDCoverage();
 }
 
 void GrDistanceFieldLCDTextureEffect::getGLProcessorKey(const GrBatchTracker& bt,
                                                         const GrGLCaps& caps,
@@ skipping 28 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////
 
 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(GrDistanceFieldLCDTextureEffect);
 
 GrGeometryProcessor* GrDistanceFieldLCDTextureEffect::TestCreate(SkRandom* random,
                                                                  GrContext*,
                                                                  const GrDrawTargetCaps&,
                                                                  GrTexture* textures[]) {
     int texIdx = random->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx :
                                       GrProcessorUnitTest::kAlphaTextureIdx;
-    int texIdx2 = random->nextBool() ? GrProcessorUnitTest::kSkiaPMTextureIdx :
-                                       GrProcessorUnitTest::kAlphaTextureIdx;
     static const SkShader::TileMode kTileModes[] = {
         SkShader::kClamp_TileMode,
         SkShader::kRepeat_TileMode,
         SkShader::kMirror_TileMode,
     };
     SkShader::TileMode tileModes[] = {
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
         kTileModes[random->nextULessThan(SK_ARRAY_COUNT(kTileModes))],
     };
     GrTextureParams params(tileModes, random->nextBool() ? GrTextureParams::kBilerp_FilterMode :
                            GrTextureParams::kNone_FilterMode);
-    GrTextureParams params2(tileModes, random->nextBool() ? GrTextureParams::kBilerp_FilterMode :
-                           GrTextureParams::kNone_FilterMode);
-    GrColor textColor = GrColorPackRGBA(random->nextULessThan(256),
-                                        random->nextULessThan(256),
-                                        random->nextULessThan(256),
-                                        random->nextULessThan(256));
+    WidthAdjust wa = { 0.0f, 0.1f, -0.1f };
     uint32_t flags = kUseLCD_DistanceFieldEffectFlag;
     flags |= random->nextBool() ? kUniformScale_DistanceFieldEffectMask : 0;
     flags |= random->nextBool() ? kBGR_DistanceFieldEffectFlag : 0;
     return GrDistanceFieldLCDTextureEffect::Create(GrRandomColor(random),
                                                    GrProcessorUnitTest::TestMatrix(random),
                                                    textures[texIdx], params,
-                                                   textures[texIdx2], params2,
-                                                   textColor,
+                                                   wa,
                                                    flags);
 }