commit 7f23543d1d27452ac1ddc21cc0c9f88479920cde
author Brian Salomon <bsalomon@google.com> Wed Aug 16 09:41:48 2017 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Wed Aug 16 14:32:28 2017 +0000
tree 298d9b33fa888188a32a631149b7a56c9ad7446c
parent c902ff8fc8bd3c385096bdbb0fec6d1ce3c231a3

Minor geometry processor clarification.

Some renames, comments, and override->final

Change-Id: Iebc7aeee9a64021e958f76bf4278ffff56884a56
Reviewed-on: https://skia-review.googlesource.com/35165
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

src/gpu/glsl/GrGLSLGeometryProcessor.cpp

diff --git a/src/gpu/glsl/GrGLSLGeometryProcessor.cpp b/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
index 3ab5b68..a390036 100644
--- a/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
+++ b/src/gpu/glsl/GrGLSLGeometryProcessor.cpp
@@ -85,19 +85,19 @@
     SkASSERT(i == fInstalledTransforms.count());
 }
 
-void GrGLSLGeometryProcessor::setupPosition(GrGLSLVertexBuilder* vertBuilder,
-                                            GrGPArgs* gpArgs,
-                                            const char* posName) {
+void GrGLSLGeometryProcessor::writeOutputPosition(GrGLSLVertexBuilder* vertBuilder,
+                                                  GrGPArgs* gpArgs,
+                                                  const char* posName) {
     gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
     vertBuilder->codeAppendf("float2 %s = %s;", gpArgs->fPositionVar.c_str(), posName);
 }
 
-void GrGLSLGeometryProcessor::setupPosition(GrGLSLVertexBuilder* vertBuilder,
-                                            GrGLSLUniformHandler* uniformHandler,
-                                            GrGPArgs* gpArgs,
-                                            const char* posName,
-                                            const SkMatrix& mat,
-                                            UniformHandle* viewMatrixUniform) {
+void GrGLSLGeometryProcessor::writeOutputPosition(GrGLSLVertexBuilder* vertBuilder,
+                                                  GrGLSLUniformHandler* uniformHandler,
+                                                  GrGPArgs* gpArgs,
+                                                  const char* posName,
+                                                  const SkMatrix& mat,
+                                                  UniformHandle* viewMatrixUniform) {
     if (mat.isIdentity()) {
         gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
         vertBuilder->codeAppendf("float2 %s = %s;", gpArgs->fPositionVar.c_str(), posName);

src/gpu/glsl/GrGLSLGeometryProcessor.h

diff --git a/src/gpu/glsl/GrGLSLGeometryProcessor.h b/src/gpu/glsl/GrGLSLGeometryProcessor.h
index 10a4aa8..17a6779 100644
--- a/src/gpu/glsl/GrGLSLGeometryProcessor.h
+++ b/src/gpu/glsl/GrGLSLGeometryProcessor.h
@@ -20,10 +20,10 @@
 class GrGLSLGeometryProcessor : public GrGLSLPrimitiveProcessor {
 public:
     /* Any general emit code goes in the base class emitCode.  Subclasses override onEmitCode */
-    void emitCode(EmitArgs&) override;
+    void emitCode(EmitArgs&) final;
 
 protected:
-    // A helper which subclasses can use if needed and used above in the default setTransformData().
+    // A helper which subclasses can use to upload coord transform matrices in setData().
     void setTransformDataHelper(const SkMatrix& localMatrix,
                                 const GrGLSLProgramDataManager& pdman,
                                 FPCoordTransformIter*);
@@ -39,7 +39,7 @@
                              posVar, localCoords, SkMatrix::I(), handler);
     }
 
-    // Emit pre-transformed coords as a vertex attribute per coord-transform.
+    // Emit pre-transformed coords as a varying per coord-transform.
     void emitTransforms(GrGLSLVertexBuilder*,
                         GrGLSLVaryingHandler*,
                         GrGLSLUniformHandler*,
@@ -49,19 +49,25 @@
                         FPCoordTransformHandler*);
 
     struct GrGPArgs {
-        // The variable used by a GP to store its position. It can be
-        // either a float2 or a float3 depending on the presence of perspective.
+        // Used to specify the output variable used by the GP to store its device position. It can
+        // either be a float2 or a float3 (in order to handle perspective). The subclass sets this
+        // in its onEmitCode().
         GrShaderVar fPositionVar;
     };
 
-    // Create the correct type of position variable given the CTM
-    void setupPosition(GrGLSLVertexBuilder*, GrGPArgs*, const char* posName);
-    void setupPosition(GrGLSLVertexBuilder*,
-                       GrGLSLUniformHandler* uniformHandler,
-                       GrGPArgs*,
-                       const char* posName,
-                       const SkMatrix& mat,
-                       UniformHandle* viewMatrixUniform);
+    // Helpers for adding code to write the transformed vertex position. The first simple version
+    // just writes a variable named by 'posName' into the position output variable with the
+    // assumption that the position is 2D. The second version transforms the input position by a
+    // view matrix and the output variable is 2D or 3D depending on whether the view matrix is
+    // perspective. Both versions declare the output position variable and will set
+    // GrGPArgs::fPositionVar.
+    void writeOutputPosition(GrGLSLVertexBuilder*, GrGPArgs*, const char* posName);
+    void writeOutputPosition(GrGLSLVertexBuilder*,
+                             GrGLSLUniformHandler* uniformHandler,
+                             GrGPArgs*,
+                             const char* posName,
+                             const SkMatrix& mat,
+                             UniformHandle* viewMatrixUniform);
 
     static uint32_t ComputePosKey(const SkMatrix& mat) {
         if (mat.isIdentity()) {