Revert "Revert "Change how vertex/instance attributes are handled in geometry processors.""

This reverts commit 5045e501d2aec23e5f1e4b46346033ac3202c6b0.

TBR=csmartdalton@google.com

Change-Id: Ifbf5f1d8f8ef340fdc69653e931b6d68d4bf0854
Reviewed-on: https://skia-review.googlesource.com/135862
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

1 files changed, 31 insertions, 20 deletions

diff --git a/tests/GrMeshTest.cpp b/tests/GrMeshTest.cpp
index 4d9773b1a9..f95dbc8603 100644
--- a/tests/GrMeshTest.cpp
+++ b/tests/GrMeshTest.cpp
@@ -294,35 +294,46 @@ private:
 class GrMeshTestProcessor : public GrGeometryProcessor {
 public:
     GrMeshTestProcessor(bool instanced, bool hasVertexBuffer)
-        : INHERITED(kGrMeshTestProcessor_ClassID)
-        , fInstanceLocation(nullptr)
-        , fVertex(nullptr)
-        , fColor(nullptr) {
+            : INHERITED(kGrMeshTestProcessor_ClassID) {
         if (instanced) {
-            fInstanceLocation = &this->addInstanceAttrib("location", kHalf2_GrVertexAttribType);
+            fInstanceLocation = {"location", kHalf2_GrVertexAttribType};
+            fColor = {"color", kUByte4_norm_GrVertexAttribType};
+            this->setInstanceAttributeCnt(2);
             if (hasVertexBuffer) {
-                fVertex = &this->addVertexAttrib("vertex", kHalf2_GrVertexAttribType);
+                fVertex = {"vertex", kHalf2_GrVertexAttribType};
+                this->setVertexAttributeCnt(1);
             }
-            fColor = &this->addInstanceAttrib("color", kUByte4_norm_GrVertexAttribType);
         } else {
-            fVertex = &this->addVertexAttrib("vertex", kHalf2_GrVertexAttribType);
-            fColor = &this->addVertexAttrib("color", kUByte4_norm_GrVertexAttribType);
+            fVertex = {"vertex", kHalf2_GrVertexAttribType};
+            fColor = {"color", kUByte4_norm_GrVertexAttribType};
+            this->setVertexAttributeCnt(2);
         }
     }
 
     const char* name() const override { return "GrMeshTest Processor"; }
 
     void getGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder* b) const final {
-        b->add32(SkToBool(fInstanceLocation));
-        b->add32(SkToBool(fVertex));
+        b->add32(fInstanceLocation.isInitialized());
+        b->add32(fVertex.isInitialized());
     }
 
     GrGLSLPrimitiveProcessor* createGLSLInstance(const GrShaderCaps&) const final;
 
-protected:
-    const Attribute* fInstanceLocation;
-    const Attribute* fVertex;
-    const Attribute* fColor;
+private:
+    const Attribute& onVertexAttribute(int i) const override {
+        if (fInstanceLocation.isInitialized()) {
+            return fVertex;
+        }
+        return IthAttribute(i, fVertex, fColor);
+    }
+
+    const Attribute& onInstanceAttribute(int i) const override {
+        return IthAttribute(i, fInstanceLocation, fColor);
+    }
+
+    Attribute fInstanceLocation;
+    Attribute fVertex;
+    Attribute fColor;
 
     friend class GLSLMeshTestProcessor;
     typedef GrGeometryProcessor INHERITED;
@@ -340,15 +351,15 @@ class GLSLMeshTestProcessor : public GrGLSLGeometryProcessor {
         varyingHandler->addPassThroughAttribute(mp.fColor, args.fOutputColor);
 
         GrGLSLVertexBuilder* v = args.fVertBuilder;
-        if (!mp.fInstanceLocation) {
-            v->codeAppendf("float2 vertex = %s;", mp.fVertex->name());
+        if (!mp.fInstanceLocation.isInitialized()) {
+            v->codeAppendf("float2 vertex = %s;", mp.fVertex.name());
         } else {
-            if (mp.fVertex) {
-                v->codeAppendf("float2 offset = %s;", mp.fVertex->name());
+            if (mp.fVertex.isInitialized()) {
+                v->codeAppendf("float2 offset = %s;", mp.fVertex.name());
             } else {
                 v->codeAppend ("float2 offset = float2(sk_VertexID / 2, sk_VertexID % 2);");
             }
-            v->codeAppendf("float2 vertex = %s + offset * %i;", mp.fInstanceLocation->name(),
+            v->codeAppendf("float2 vertex = %s + offset * %i;", mp.fInstanceLocation.name(),
                            kBoxSize);
         }
         gpArgs->fPositionVar.set(kFloat2_GrSLType, "vertex");