Add a workaround for inaccurate interpolants on Adreno 3xx.
Also ensure that sk_FragCoord x and y values are at pixel centers when
workaround is used.
Change-Id: Ib748af9e496a406a50622e00e96e1346cbb5eb26
Reviewed-on: https://skia-review.googlesource.com/97064
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/ops/GrTextureOp.cpp b/src/gpu/ops/GrTextureOp.cpp
index 7c4842f..46d2630 100644
--- a/src/gpu/ops/GrTextureOp.cpp
+++ b/src/gpu/ops/GrTextureOp.cpp
@@ -168,22 +168,51 @@
}
args.fFragBuilder->codeAppend(";");
if (textureGP.usesCoverageEdgeAA()) {
- GrGLSLVarying aaDistVarying(kFloat4_GrSLType,
- GrGLSLVarying::Scope::kVertToFrag);
- args.fVaryingHandler->addVarying("aaDists", &aaDistVarying);
- args.fVertBuilder->codeAppendf(
- R"(%s = float4(dot(aaEdge0.xy, %s.xy) + aaEdge0.z,
- dot(aaEdge1.xy, %s.xy) + aaEdge1.z,
- dot(aaEdge2.xy, %s.xy) + aaEdge2.z,
- dot(aaEdge3.xy, %s.xy) + aaEdge3.z);)",
- aaDistVarying.vsOut(), textureGP.fPositions.fName,
- textureGP.fPositions.fName, textureGP.fPositions.fName,
- textureGP.fPositions.fName);
-
+ const char* aaDistName = nullptr;
+ // When interpolation is innacurate we perform the evaluation of the edge
+ // equations in the fragment shader rather than interpolating values computed
+ // in the vertex shader.
+ if (!args.fShaderCaps->interpolantsAreInaccurate()) {
+ GrGLSLVarying aaDistVarying(kFloat4_GrSLType,
+ GrGLSLVarying::Scope::kVertToFrag);
+ args.fVaryingHandler->addVarying("aaDists", &aaDistVarying);
+ args.fVertBuilder->codeAppendf(
+ R"(%s = float4(dot(aaEdge0.xy, %s.xy) + aaEdge0.z,
+ dot(aaEdge1.xy, %s.xy) + aaEdge1.z,
+ dot(aaEdge2.xy, %s.xy) + aaEdge2.z,
+ dot(aaEdge3.xy, %s.xy) + aaEdge3.z);)",
+ aaDistVarying.vsOut(), textureGP.fPositions.fName,
+ textureGP.fPositions.fName, textureGP.fPositions.fName,
+ textureGP.fPositions.fName);
+ aaDistName = aaDistVarying.fsIn();
+ } else {
+ GrGLSLVarying aaEdgeVarying[4]{
+ {kFloat3_GrSLType, GrGLSLVarying::Scope::kVertToFrag},
+ {kFloat3_GrSLType, GrGLSLVarying::Scope::kVertToFrag},
+ {kFloat3_GrSLType, GrGLSLVarying::Scope::kVertToFrag},
+ {kFloat3_GrSLType, GrGLSLVarying::Scope::kVertToFrag}
+ };
+ for (int i = 0; i < 4; ++i) {
+ SkString name;
+ name.printf("aaEdge%d", i);
+ args.fVaryingHandler->addVarying(name.c_str(), &aaEdgeVarying[i]);
+ args.fVertBuilder->codeAppendf(
+ "%s = aaEdge%d;", aaEdgeVarying[i].vsOut(), i);
+ }
+ args.fFragBuilder->codeAppendf(
+ R"(float4 aaDists = float4(dot(%s.xy, sk_FragCoord.xy) + %s.z,
+ dot(%s.xy, sk_FragCoord.xy) + %s.z,
+ dot(%s.xy, sk_FragCoord.xy) + %s.z,
+ dot(%s.xy, sk_FragCoord.xy) + %s.z);)",
+ aaEdgeVarying[0].fsIn(), aaEdgeVarying[0].fsIn(),
+ aaEdgeVarying[1].fsIn(), aaEdgeVarying[1].fsIn(),
+ aaEdgeVarying[2].fsIn(), aaEdgeVarying[2].fsIn(),
+ aaEdgeVarying[3].fsIn(), aaEdgeVarying[3].fsIn());
+ aaDistName = "aaDists";
+ }
args.fFragBuilder->codeAppendf(
"float mindist = min(min(%s.x, %s.y), min(%s.z, %s.w));",
- aaDistVarying.fsIn(), aaDistVarying.fsIn(), aaDistVarying.fsIn(),
- aaDistVarying.fsIn());
+ aaDistName, aaDistName, aaDistName, aaDistName);
args.fFragBuilder->codeAppendf("%s = float4(clamp(mindist, 0, 1));",
args.fOutputCoverage);
} else {