Refactor position computation to enable device space "nudge"

src/gpu/GrOvalRenderer.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 "GrOvalRenderer.h"
 
 #include "GrProcessor.h"
@@ skipping 65 matching lines @@
     const char* name() const SK_OVERRIDE { return "CircleEdge"; }
 
     inline bool isStroked() const { return fStroke; }
 
     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 CircleEdgeEffect& ce = args.fGP.cast<CircleEdgeEffect>();
             GrGLGPBuilder* pb = args.fPB;
             const BatchTracker& local = args.fBT.cast<BatchTracker>();
             GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
 
             // emit attributes
             vsBuilder->emitAttributes(ce);
 
             GrGLVertToFrag v(kVec4f_GrSLType);
             args.fPB->addVarying("CircleEdge", &v);
             vsBuilder->codeAppendf("%s = %s;", v.vsOut(), ce.inCircleEdge()->fName);
 
             // 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(),
-                                   ce.inPosition()->fName);
+            SetupPosition(vsBuilder, gpArgs, ce.inPosition()->fName,
+                          ce.viewMatrix(), this->uViewM());
 
             // emit transforms
-            this->emitTransforms(args.fPB,  this->position(), ce.inPosition()->fName,
+            this->emitTransforms(args.fPB, gpArgs->fPositionVar, ce.inPosition()->fName,
                                  ce.localMatrix(), args.fTransformsIn, args.fTransformsOut);;
 
             GrGLGPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
             fsBuilder->codeAppendf("float d = length(%s.xy);", v.fsIn());
             fsBuilder->codeAppendf("float edgeAlpha = clamp(%s.z * (1.0 - d), 0.0, 1.0);", v.fsIn());
             if (ce.isStroked()) {
                 fsBuilder->codeAppendf("float innerAlpha = clamp(%s.z * (d - %s.w), 0.0, 1.0);",
                                        v.fsIn(), v.fsIn());
                 fsBuilder->codeAppend("edgeAlpha *= innerAlpha;");
             }
 
             fsBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
         }
 
-        static void GenKey(const GrGeometryProcessor& processor,
+        static void GenKey(const GrGeometryProcessor& gp,
                            const GrBatchTracker& bt,
                            const GrGLCaps&,
                            GrProcessorKeyBuilder* b) {
             const BatchTracker& local = bt.cast<BatchTracker>();
-            const CircleEdgeEffect& circleEffect = processor.cast<CircleEdgeEffect>();
+            const CircleEdgeEffect& circleEffect = gp.cast<CircleEdgeEffect>();
             uint16_t key = circleEffect.isStroked() ? 0x1 : 0x0;
-            key |= local.fUsesLocalCoords && processor.localMatrix().hasPerspective() ? 0x2 : 0x0;
+            key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x2 : 0x0;
+            key |= ComputePosKey(gp.viewMatrix()) << 2;
             b->add32(key << 16 | local.fInputColorType);
         }
 
         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) {
@@ skipping 108 matching lines @@
     const Attribute* inEllipseRadii() const { return fInEllipseRadii; }
 
     inline bool isStroked() const { return fStroke; }
 
     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 EllipseEdgeEffect& ee = args.fGP.cast<EllipseEdgeEffect>();
             GrGLGPBuilder* pb = args.fPB;
             const BatchTracker& local = args.fBT.cast<BatchTracker>();
             GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
 
             // emit attributes
             vsBuilder->emitAttributes(ee);
 
             GrGLVertToFrag ellipseOffsets(kVec2f_GrSLType);
             args.fPB->addVarying("EllipseOffsets", &ellipseOffsets);
             vsBuilder->codeAppendf("%s = %s;", ellipseOffsets.vsOut(),
                                    ee.inEllipseOffset()->fName);
 
             GrGLVertToFrag ellipseRadii(kVec4f_GrSLType);
             args.fPB->addVarying("EllipseRadii", &ellipseRadii);
             vsBuilder->codeAppendf("%s = %s;", ellipseRadii.vsOut(),
                                    ee.inEllipseRadii()->fName);
 
             // 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(),
-                                   ee.inPosition()->fName);
+            SetupPosition(vsBuilder, gpArgs, ee.inPosition()->fName,
+                          ee.viewMatrix(), this->uViewM());
 
             // emit transforms
-            this->emitTransforms(args.fPB, this->position(), ee.inPosition()->fName,
+            this->emitTransforms(args.fPB, gpArgs->fPositionVar, ee.inPosition()->fName,
                                  ee.localMatrix(), args.fTransformsIn, args.fTransformsOut);
 
             // for outer curve
             GrGLGPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
             fsBuilder->codeAppendf("vec2 scaledOffset = %s*%s.xy;", ellipseOffsets.fsIn(),
                                    ellipseRadii.fsIn());
             fsBuilder->codeAppend("float test = dot(scaledOffset, scaledOffset) - 1.0;");
             fsBuilder->codeAppendf("vec2 grad = 2.0*scaledOffset*%s.xy;", ellipseRadii.fsIn());
             fsBuilder->codeAppend("float grad_dot = dot(grad, grad);");
 
             // avoid calling inversesqrt on zero.
             fsBuilder->codeAppend("grad_dot = max(grad_dot, 1.0e-4);");
             fsBuilder->codeAppend("float invlen = inversesqrt(grad_dot);");
             fsBuilder->codeAppend("float edgeAlpha = clamp(0.5-test*invlen, 0.0, 1.0);");
 
             // for inner curve
             if (ee.isStroked()) {
                 fsBuilder->codeAppendf("scaledOffset = %s*%s.zw;",
                                        ellipseOffsets.fsIn(), ellipseRadii.fsIn());
                 fsBuilder->codeAppend("test = dot(scaledOffset, scaledOffset) - 1.0;");
                 fsBuilder->codeAppendf("grad = 2.0*scaledOffset*%s.zw;",
                                        ellipseRadii.fsIn());
                 fsBuilder->codeAppend("invlen = inversesqrt(dot(grad, grad));");
                 fsBuilder->codeAppend("edgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);");
             }
 
             fsBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
         }
 
-        static void GenKey(const GrGeometryProcessor& processor,
+        static void GenKey(const GrGeometryProcessor& gp,
                            const GrBatchTracker& bt,
                            const GrGLCaps&,
                            GrProcessorKeyBuilder* b) {
             const BatchTracker& local = bt.cast<BatchTracker>();
-            const EllipseEdgeEffect& ellipseEffect = processor.cast<EllipseEdgeEffect>();
+            const EllipseEdgeEffect& ellipseEffect = gp.cast<EllipseEdgeEffect>();
             uint16_t key = ellipseEffect.isStroked() ? 0x1 : 0x0;
-            key |= local.fUsesLocalCoords && processor.localMatrix().hasPerspective() ? 0x2 : 0x0;
+            key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x2 : 0x0;
+            key |= ComputePosKey(gp.viewMatrix()) << 2;
             b->add32(key << 16 | local.fInputColorType);
         }
 
         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) {
@@ skipping 115 matching lines @@
     const Attribute* inEllipseOffsets1() const { return fInEllipseOffsets1; }
 
     inline Mode getMode() const { return fMode; }
 
     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 DIEllipseEdgeEffect& ee = args.fGP.cast<DIEllipseEdgeEffect>();
             GrGLGPBuilder* pb = args.fPB;
             const BatchTracker& local = args.fBT.cast<BatchTracker>();
             GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
 
             // emit attributes
             vsBuilder->emitAttributes(ee);
 
             GrGLVertToFrag offsets0(kVec2f_GrSLType);
             args.fPB->addVarying("EllipseOffsets0", &offsets0);
             vsBuilder->codeAppendf("%s = %s;", offsets0.vsOut(),
                                    ee.inEllipseOffsets0()->fName);
 
             GrGLVertToFrag offsets1(kVec2f_GrSLType);
             args.fPB->addVarying("EllipseOffsets1", &offsets1);
             vsBuilder->codeAppendf("%s = %s;", offsets1.vsOut(),
                                    ee.inEllipseOffsets1()->fName);
 
             // 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(),
-                                   ee.inPosition()->fName);
+            SetupPosition(vsBuilder, gpArgs, ee.inPosition()->fName,
+                          ee.viewMatrix(), this->uViewM());
 
             // emit transforms
-            this->emitTransforms(args.fPB, this->position(), ee.inPosition()->fName,
+            this->emitTransforms(args.fPB, gpArgs->fPositionVar, ee.inPosition()->fName,
                                  ee.localMatrix(), args.fTransformsIn, args.fTransformsOut);
 
             GrGLGPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder();
             SkAssertResult(fsBuilder->enableFeature(
                     GrGLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
             // for outer curve
             fsBuilder->codeAppendf("vec2 scaledOffset = %s.xy;", offsets0.fsIn());
             fsBuilder->codeAppend("float test = dot(scaledOffset, scaledOffset) - 1.0;");
             fsBuilder->codeAppendf("vec2 duvdx = dFdx(%s);", offsets0.fsIn());
             fsBuilder->codeAppendf("vec2 duvdy = dFdy(%s);", offsets0.fsIn());
@@ skipping 23 matching lines @@
                                        "            2.0*%s.x*duvdy.x + 2.0*%s.y*duvdy.y);",
                                        offsets1.fsIn(), offsets1.fsIn(), offsets1.fsIn(),
                                        offsets1.fsIn());
                 fsBuilder->codeAppend("invlen = inversesqrt(dot(grad, grad));");
                 fsBuilder->codeAppend("edgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);");
             }
 
             fsBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
         }
 
-        static void GenKey(const GrGeometryProcessor& processor,
+        static void GenKey(const GrGeometryProcessor& gp,
                            const GrBatchTracker& bt,
                            const GrGLCaps&,
                            GrProcessorKeyBuilder* b) {
             const BatchTracker& local = bt.cast<BatchTracker>();
-            const DIEllipseEdgeEffect& ellipseEffect = processor.cast<DIEllipseEdgeEffect>();
+            const DIEllipseEdgeEffect& ellipseEffect = gp.cast<DIEllipseEdgeEffect>();
             uint16_t key = ellipseEffect.getMode();
-            key |= local.fUsesLocalCoords && processor.localMatrix().hasPerspective() ? 0x1 << 8 :
-                                                                                        0x0;
+            key |= local.fUsesLocalCoords && gp.localMatrix().hasPerspective() ? 0x1 << 8 : 0x0;
+            key |= ComputePosKey(gp.viewMatrix()) << 9;
             b->add32(key << 16 | local.fInputColorType);
         }
 
         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) {
@@ skipping 850 matching lines @@
         int indexCnt = isStrokeOnly ? SK_ARRAY_COUNT(gRRectIndices) - 6 :
                                       SK_ARRAY_COUNT(gRRectIndices);
         target->setIndexSourceToBuffer(indexBuffer);
         target->drawIndexedInstances(drawState, effect, kTriangles_GrPrimitiveType, 1, 16, indexCnt,
                                      &bounds);
     }
 
     target->resetIndexSource();
     return true;
 }