Added varying struct

src/gpu/gl/builders/GrGLProgramBuilder.h

Index: src/gpu/gl/builders/GrGLProgramBuilder.h
diff --git a/src/gpu/gl/builders/GrGLProgramBuilder.h b/src/gpu/gl/builders/GrGLProgramBuilder.h
index 2afdd099f4322abf2246bedb0181137159808df0..9d8e7e0ac9657ee6844d7b43a85c925be0305143 100644
--- a/src/gpu/gl/builders/GrGLProgramBuilder.h
+++ b/src/gpu/gl/builders/GrGLProgramBuilder.h
@@ -69,13 +69,63 @@ public:
      */
 };
 
+// TODO move this into GrGLGPBuilder and move them both out of this file
+class GrGLVarying {
+public:
+    bool vsVarying() const { return kVertToFrag_Varying == fVarying ||
+                                    kVertToGeo_Varying == fVarying; }
+    bool fsVarying() const { return kVertToFrag_Varying == fVarying ||
+                                    kGeoToFrag_Varying == fVarying; }
+    const char* vsOut() const { return fVsOut; }
+    const char* gsIn() const { return fGsIn; }
+    const char* gsOut() const { return fGsOut; }
+    const char* fsIn() const { return fFsIn; }
+
+protected:
+    enum Varying {
+        kVertToFrag_Varying,
+        kVertToGeo_Varying,
+        kGeoToFrag_Varying,
+    };
+
+    GrGLVarying(GrSLType type, Varying varying)
+        : fVarying(varying), fType(type), fVsOut(NULL), fGsIn(NULL), fGsOut(NULL),
+          fFsIn(NULL) {}
+
+    Varying fVarying;
+
+private:
+    GrSLType fType;
+    const char* fVsOut;
+    const char* fGsIn;
+    const char* fGsOut;
+    const char* fFsIn;
+
+    friend class GrGLVertexBuilder;
+    friend class GrGLGeometryBuilder;
+    friend class GrGLFragmentShaderBuilder;
+};
+
+struct GrGLVertToFrag : public GrGLVarying {
+    GrGLVertToFrag(GrSLType type)
+        : GrGLVarying(type, kVertToFrag_Varying) {}
+};
+
+struct GrGLVertToGeo : public GrGLVarying {
+    GrGLVertToGeo(GrSLType type)
+        : GrGLVarying(type, kVertToGeo_Varying) {}
+};
+
+struct GrGLGeoToFrag : public GrGLVarying {
+    GrGLGeoToFrag(GrSLType type)
+        : GrGLVarying(type, kGeoToFrag_Varying) {}
+};
+
 /* a specialization of the above for GPs.  Lets the user add uniforms, varyings, and VS / FS code */
 class GrGLGPBuilder : public virtual GrGLUniformBuilder {
 public:
-    virtual void addVarying(GrSLType type,
-                            const char* name,
-                            const char** vsOutName = NULL,
-                            const char** fsInName = NULL,
+    virtual void addVarying(const char* name,
+                            GrGLVarying*,
                             GrGLShaderVar::Precision fsPrecision=GrGLShaderVar::kDefault_Precision) = 0;
 
     // TODO rename getFragmentBuilder
@@ -152,10 +202,8 @@ public:
     virtual GrGLVertexBuilder* getVertexShaderBuilder() SK_OVERRIDE { return &fVS; }
 
     virtual void addVarying(
-            GrSLType type,
             const char* name,
-            const char** vsOutName = NULL,
-            const char** fsInName = NULL,
+            GrGLVarying*,
             GrGLShaderVar::Precision fsPrecision=GrGLShaderVar::kDefault_Precision) SK_OVERRIDE;
 
     // Handles for program uniforms (other than per-effect uniforms)