Revert of Remove gpu support for willUseHWAALines.

src/gpu/GrDrawTarget.cpp

 
 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 
@@ skipping 595 matching lines @@
     if (this->caps()->gpuTracingSupport()) {
         SkASSERT(fGpuTraceMarkerCount >= 1);
         this->fActiveTraceMarkers.remove(*marker);
         this->didRemoveGpuTraceMarker();
         --fGpuTraceMarkerCount;
     }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
+bool GrDrawTarget::willUseHWAALines() const {
+    // There is a conflict between using smooth lines and our use of premultiplied alpha. Smooth
+    // lines tweak the incoming alpha value but not in a premul-alpha way. So we only use them when
+    // our alpha is 0xff and tweaking the color for partial coverage is OK
+    if (!this->caps()->hwAALineSupport() ||
+        !this->getDrawState().isHWAntialiasState()) {
+        return false;
+    }
+    GrDrawState::BlendOptFlags opts = this->getDrawState().getBlendOpts();
+    return (GrDrawState::kDisableBlend_BlendOptFlag & opts) &&
+           (GrDrawState::kCoverageAsAlpha_BlendOptFlag & opts);
+}
+
 bool GrDrawTarget::canApplyCoverage() const {
     // we can correctly apply coverage if a) we have dual source blending
-    // or b) one of our blend optimizations applies 
-    // or c) the src/dst coefficients are 1, 0 respectively.
-    GrBlendCoeff srcCoeff; 
-    GrBlendCoeff dstCoeff; 
+    // or b) one of our blend optimizations applies.
     return this->caps()->dualSourceBlendingSupport() ||
-           GrDrawState::kNone_BlendOpt != this->getDrawState().getBlendOpts(true, &srcCoeff,
-                                                                            &dstCoeff) ||
-           (kOne_GrBlendCoeff == srcCoeff && kZero_GrBlendCoeff == dstCoeff);
+           GrDrawState::kNone_BlendOpt != this->getDrawState().getBlendOpts(true);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 void GrDrawTarget::drawIndexedInstances(GrPrimitiveType type,
                                         int instanceCount,
                                         int verticesPerInstance,
                                         int indicesPerInstance,
                                         const SkRect* devBounds) {
     if (!verticesPerInstance || !indicesPerInstance) {
@@ skipping 512 matching lines @@
     SkASSERT(!fConfigTextureSupport[kUnknown_GrPixelConfig]);
 
     for (size_t i = 1; i < SK_ARRAY_COUNT(kConfigNames); ++i)  {
         r.appendf("%s is uploadable to a texture: %s\n",
                   kConfigNames[i],
                   gNY[fConfigTextureSupport[i]]);
     }
 
     return r;
 }