commit c3318f09cdf181f7c6e26a9445f4ceb839d41b7b
author Chris Dalton <csmartdalton@google.com> Fri Jul 19 14:20:53 2019 -0600
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Fri Jul 19 20:52:17 2019 +0000
tree 9eec928483cbf916bb2011ecf0c3d53e11301a85
parent 4a13119a60e25c75c4c4d6d99d852f3e8b3346e1

ccpr: Add an MSAA atlas mode

Adds the option to use a multisampled (or mixed sampled) atlas, and
uses the sample mask and stencil buffer instead of coverage counts.

Bug: skia:
Change-Id: I9fb76d17895ae25208124f6c27e37977ac31b5eb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/227428
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

src/gpu/ccpr/GrCCQuadraticShader.cpp

diff --git a/src/gpu/ccpr/GrCCQuadraticShader.cpp b/src/gpu/ccpr/GrCCQuadraticShader.cpp
index 5ad7d55..5012e3c 100644
--- a/src/gpu/ccpr/GrCCQuadraticShader.cpp
+++ b/src/gpu/ccpr/GrCCQuadraticShader.cpp
@@ -42,11 +42,14 @@
     code->appendf("%s.zw = 2*bloat * float2(2 * %s.x, -1) * %s;",  // Gradient.
                   OutName(fCoord_fGrad), OutName(fCoord_fGrad), fQCoordMatrix.c_str());
 
-    // Coverages need full precision since distance to the opposite edge can be large.
-    fEdge_fWind_fCorner.reset(cornerCoverage ? kFloat4_GrSLType : kFloat2_GrSLType, scope);
-    varyingHandler->addVarying("edge_and_wind_and_corner", &fEdge_fWind_fCorner);
-    code->appendf("%s.x = %s;", OutName(fEdge_fWind_fCorner), coverage);
-    code->appendf("%s.y = %s;", OutName(fEdge_fWind_fCorner), wind);
+    if (coverage) {
+        // Coverages need full precision since distance to the opposite edge can be large.
+        fEdge_fWind_fCorner.reset((cornerCoverage) ? kFloat4_GrSLType : kFloat2_GrSLType, scope);
+        varyingHandler->addVarying((cornerCoverage) ? "edge_and_wind_and_corner" : "edge_and_wind",
+                                   &fEdge_fWind_fCorner);
+        code->appendf("%s.x = %s;", OutName(fEdge_fWind_fCorner), coverage);
+        code->appendf("%s.y = %s;", OutName(fEdge_fWind_fCorner), wind);
+    }
 
     if (cornerCoverage) {
         SkASSERT(coverage);
@@ -57,7 +60,7 @@
     }
 }
 
-void GrCCQuadraticShader::onEmitFragmentCode(
+void GrCCQuadraticShader::emitFragmentCoverageCode(
         GrGLSLFPFragmentBuilder* f, const char* outputCoverage) const {
     this->calcHullCoverage(&AccessCodeString(f), fCoord_fGrad.fsIn(),
                            SkStringPrintf("%s.x", fEdge_fWind_fCorner.fsIn()).c_str(),
@@ -83,3 +86,10 @@
     // Total hull coverage.
     code->appendf("%s = max(half(curve_coverage + edge_coverage), 0);", outputCoverage);
 }
+
+void GrCCQuadraticShader::emitSampleMaskCode(GrGLSLFPFragmentBuilder* f) const {
+    f->codeAppendf("float x = %s.x, y = %s.y;", fCoord_fGrad.fsIn(), fCoord_fGrad.fsIn());
+    f->codeAppendf("float f = x*x - y;");
+    f->codeAppendf("float2 grad = %s.zw;", fCoord_fGrad.fsIn());
+    f->applyFnToMultisampleMask("f", "grad", GrGLSLFPFragmentBuilder::ScopeFlags::kTopLevel);
+}