Refactor position computation to enable device space "nudge"

src/gpu/GrAAConvexPathRenderer.cpp

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrAAConvexPathRenderer.h"
 
@@ skipping 517 matching lines @@
 
     const Attribute* inPosition() const { return fInPosition; }
     const Attribute* inQuadEdge() const { return fInQuadEdge; }
 
     class GLProcessor : public GrGLGeometryProcessor {
     public:
         GLProcessor(const GrGeometryProcessor&,
                     const GrBatchTracker&)
             : fColor(GrColor_ILLEGAL) {}
 
-        void onEmitCode(EmitArgs& args) SK_OVERRIDE {
+        void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) SK_OVERRIDE {
             const QuadEdgeEffect& qe = args.fGP.cast<QuadEdgeEffect>();
             GrGLGPBuilder* pb = args.fPB;
             GrGLVertexBuilder* vsBuilder = pb->getVertexShaderBuilder();
 
             // emit attributes
             vsBuilder->emitAttributes(qe);
 
             GrGLVertToFrag v(kVec4f_GrSLType);
             args.fPB->addVarying("QuadEdge", &v);
             vsBuilder->codeAppendf("%s = %s;", v.vsOut(), qe.inQuadEdge()->fName);
 
             const BatchTracker& local = args.fBT.cast<BatchTracker>();
 
             // Setup pass through color
             this->setupColorPassThrough(pb, local.fInputColorType, args.fOutputColor, NULL,
                                         &fColorUniform);
 
             // setup uniform viewMatrix
             this->addUniformViewMatrix(pb);
 
             // Setup position
-            vsBuilder->codeAppendf("%s = %s * vec3(%s, 1);",  this->position(), this->uViewM(),
-                                   qe.inPosition()->fName);
+            SetupPosition(vsBuilder, gpArgs, qe.inPosition()->fName,
+                          qe.viewMatrix(), this->uViewM());
 
             // emit transforms
-            this->emitTransforms(args.fPB,  this->position(), qe.inPosition()->fName,
+            this->emitTransforms(args.fPB, gpArgs->fPositionVar, qe.inPosition()->fName,
                                  qe.localMatrix(), args.fTransformsIn, args.fTransformsOut);
 
             GrGLGPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
 
             SkAssertResult(fsBuilder->enableFeature(
                     GrGLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
             fsBuilder->codeAppendf("float edgeAlpha;");
 
             // keep the derivative instructions outside the conditional
             fsBuilder->codeAppendf("vec2 duvdx = dFdx(%s.xy);", v.fsIn());
@@ skipping 12 matching lines @@
                                    "clamp(0.5 - edgeAlpha / length(gF), 0.0, 1.0);}");
 
             fsBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
         }
 
         static inline void GenKey(const GrGeometryProcessor& gp,
                                   const GrBatchTracker& bt,
                                   const GrGLCaps&,
                                   GrProcessorKeyBuilder* b) {
             const BatchTracker& local = bt.cast<BatchTracker>();
-            b->add32((local.fInputColorType << 16) |
-                     (local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x1 : 0x0));
+            uint32_t key = local.fInputColorType << 16;
+            key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x1 : 0x0;
+            key |= ComputePosKey(gp.viewMatrix()) << 1;
+            b->add32(key);
         }
 
         virtual void setData(const GrGLProgramDataManager& pdman,
                              const GrPrimitiveProcessor& gp,
                              const GrBatchTracker& bt) SK_OVERRIDE {
             this->setUniformViewMatrix(pdman, gp.viewMatrix());
 
             const BatchTracker& local = bt.cast<BatchTracker>();
             if (kUniform_GrGPInput == local.fInputColorType && local.fColor != fColor) {
                 GrGLfloat c[4];
@@ skipping 177 matching lines @@
                             vOffset,  // start vertex
                             0,        // start index
                             draw.fVertexCnt,
                             draw.fIndexCnt,
                             &devBounds);
         vOffset += draw.fVertexCnt;
     }
 
     return true;
 }