Fix up some issues introduced by https://codereview.chromium.org/1013773002/

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"
@@ skipping 82 matching lines @@
             // 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.
 
             // this gives us a smooth step across approximately one fragment
             fsBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdx(st.x));");
         } else {
             // For general transforms, to determine the amount of correction we multiply a unit
             // vector pointing along the SDF gradient direction by the Jacobian of the st coords
             // (which is the inverse transform for this fragment) and take the length of the result.
             fsBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance), dFdy(distance));");
-            if (args.fPB->ctxInfo().caps()->dropsTileOnZeroDivide()) {
-                // this is to compensate for the Adreno, which likes to drop tiles on division by 0
-                fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
-                fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
-                fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
-                fsBuilder->codeAppend("} else {");
-                fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
-                fsBuilder->codeAppend("}");
-            } else {
-                fsBuilder->codeAppend("dist_grad = normalize(dist_grad);\n");
-            }
+            // the length of the gradient may be 0, so we need to check for this
+            // this also compensates for the Adreno, which likes to drop tiles on division by 0
+            fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
+            fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
+            fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
+            fsBuilder->codeAppend("} else {");
+            fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
+            fsBuilder->codeAppend("}");
+
             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);");
 
@@ skipping 256 matching lines @@
             // 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.
 
             // this gives us a smooth step across approximately one fragment
             fsBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdx(st.x));");
         } else {
             // For general transforms, to determine the amount of correction we multiply a unit
             // vector pointing along the SDF gradient direction by the Jacobian of the st coords
             // (which is the inverse transform for this fragment) and take the length of the result.
             fsBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance), dFdy(distance));");
-            if (args.fPB->ctxInfo().caps()->dropsTileOnZeroDivide()) {
-                // this is to compensate for the Adreno, which likes to drop tiles on division by 0
-                fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
-                fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
-                fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
-                fsBuilder->codeAppend("} else {");
-                fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
-                fsBuilder->codeAppend("}");
-            } else {
-                fsBuilder->codeAppend("dist_grad = normalize(dist_grad);");
-            }
+            // the length of the gradient may be 0, so we need to check for this
+            // this also compensates for the Adreno, which likes to drop tiles on division by 0
+            fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
+            fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
+            fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
+            fsBuilder->codeAppend("} else {");
+            fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
+            fsBuilder->codeAppend("}");
+
             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);");
 
@@ skipping 253 matching lines @@
             // 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.
 
             // this gives us a smooth step across approximately one fragment
             fsBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dx);");
         } else {
             // For general transforms, to determine the amount of correction we multiply a unit
             // vector pointing along the SDF gradient direction by the Jacobian of the st coords
             // (which is the inverse transform for this fragment) and take the length of the result.
             fsBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance.r), dFdy(distance.r));");
-            if (args.fPB->ctxInfo().caps()->dropsTileOnZeroDivide()) {
-                // this is to compensate for the Adreno, which likes to drop tiles on division by 0
-                fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
-                fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
-                fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
-                fsBuilder->codeAppend("} else {");
-                fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
-                fsBuilder->codeAppend("}");
-            } else {
-                fsBuilder->codeAppend("dist_grad = normalize(dist_grad);\n");
-            }
+            // the length of the gradient may be 0, so we need to check for this
+            // this also compensates for the Adreno, which likes to drop tiles on division by 0
+            fsBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
+            fsBuilder->codeAppend("if (dg_len2 < 0.0001) {");
+            fsBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
+            fsBuilder->codeAppend("} else {");
+            fsBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
+            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
@@ skipping 170 matching lines @@
     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,
                                                    flags);
 }