Initial refactor of shaderbuilder

src/gpu/gl/builders/GrGLVertexShaderBuilder.h

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrGLVertexShader_DEFINED
+#define GrGLVertexShader_DEFINED
+#include "GrGLShaderBuilder.h"
+
+class GrGLProgramBuilder;
+
+class GrGLVertexShaderBuilder : public GrGLFullShaderBuilder {
+public:
+    GrGLVertexShaderBuilder(GrGLFullProgramBuilder* program);
+
+    /*
+     * Add attribute will push a new attribute onto the end.  It will also assert if there is
+     * a duplicate attribute
+     */
+    bool addAttribute(GrSLType type, const char* name);
+
+    bool addEffectAttribute(int attributeIndex, GrSLType type, const SkString& name);
+
+    /*
+     * this call is only for GrGLProgramEffects' internal use
+     */
+    void emitAttributes(const GrEffectStage& stage);
+
+    /**
+     * Are explicit local coordinates provided as input to the vertex shader.
+     */
+    bool hasExplicitLocalCoords() const { return (fLocalCoordsVar != fPositionVar); }
+
+    const SkString* getEffectAttributeName(int attributeIndex) const;
+
+    /** Returns a vertex attribute that represents the local coords in the VS. This may be the same
+        as positionAttribute() or it may not be. It depends upon whether the rendering code
+        specified explicit local coords or not in the GrDrawState. */
+    const GrGLShaderVar& localCoordsAttribute() const { return *fLocalCoordsVar; }
+
+    /** Returns a vertex attribute that represents the vertex position in the VS. This is the
+        pre-matrix position and is commonly used by effects to compute texture coords via a matrix.
+      */
+    const GrGLShaderVar& positionAttribute() const { return *fPositionVar; }
+
+private:
+    /*
+     * Internal call for GrGLFullProgramBuilder.addVarying
+     */
+    void addVarying(GrSLType type,
+                   const char* name,
+                   const char** vsOutName);
+
+    /*
+     * private helpers for compilation by GrGLProgramBuilder
+     */
+    void bindProgramLocations(GrGLuint programId);
+    bool compileAndAttachShaders(GrGLuint programId, SkTDArray<GrGLuint>* shaderIds) const;
+    void emitCodeBeforeEffects(GrGLSLExpr4* color, GrGLSLExpr4* coverage);
+    void emitCodeAfterEffects();
+
+    struct AttributePair {
+        void set(int index, const SkString& name) {
+            fIndex = index; fName = name;
+        }
+        int      fIndex;
+        SkString fName;
+    };
+
+    SkSTArray<10, AttributePair, true>  fEffectAttributes;
+    GrGLShaderVar*                      fPositionVar;
+    GrGLShaderVar*                      fLocalCoordsVar;
+
+    friend class GrGLFullProgramBuilder;
+
+    typedef GrGLFullShaderBuilder INHERITED;
+};
+
+#endif