Hooks up the GrCustomStage/GrGLProgramStageFactory/GrGLProgramStage

classes from r3726 so they can be used. Does not implement any actual
effect stages.

Has one large known bug: if custom stages are provided, GrSamplerState
comparisons will break; this should preserve correct drawing, but decrease
performance - among other things, we'll break draw batching. To fix this
we'll need a RTTI system for GrCustomState objects, and we'll need to change
the GrSamplerState comparison from a memcmp to something that also does a
deep type-sensitive compare of any GrCustomState objects present.

http://codereview.appspot.com/6074043/



git-svn-id: http://skia.googlecode.com/svn/trunk@3742 2bbb7eff-a529-9590-31e7-b0007b416f81

2 files changed, 56 insertions, 2 deletions

diff --git a/include/gpu/GrCustomStage.h b/include/gpu/GrCustomStage.h
new file mode 100644
index 0000000000..25ab005472
--- /dev/null
+++ b/include/gpu/GrCustomStage.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrCustomStage_DEFINED
+#define GrCustomStage_DEFINED
+
+#include "GrRefCnt.h"
+
+class GrContext;
+class GrGLProgramStageFactory;
+
+/** Provides custom vertex shader, fragment shader, uniform data for a
+    particular stage of the Ganesh shading pipeline.
+    TODO: may want to refcount these? */
+class GrCustomStage : public GrRefCnt {
+
+public:
+
+    GrCustomStage();
+    virtual ~GrCustomStage();
+
+    /** If given an input texture that is/is not opaque, is this
+        stage guaranteed to produce an opaque output? */
+    virtual bool isOpaque(bool inputTextureIsOpaque) const;
+
+    virtual GrGLProgramStageFactory* getGLFactory() = 0;
+
+protected:
+
+};
+
+#endif
diff --git a/include/gpu/GrSamplerState.h b/include/gpu/GrSamplerState.h
index 50a6cc9ec7..d9957bd578 100644
--- a/include/gpu/GrSamplerState.h
+++ b/include/gpu/GrSamplerState.h
@@ -11,8 +11,9 @@
 #ifndef GrSamplerState_DEFINED
 #define GrSamplerState_DEFINED
 
-#include "GrTypes.h"
+#include "GrCustomStage.h"
 #include "GrMatrix.h"
+#include "GrTypes.h"
 
 #define MAX_KERNEL_WIDTH 25
 
@@ -110,12 +111,17 @@ public:
      * unfiltered, and use identity matrix.
      */
     GrSamplerState()
-    : fRadial2CenterX1()
+    : fCustomStage (NULL)
+    , fRadial2CenterX1()
     , fRadial2Radius0()
     , fRadial2PosRoot() {
         this->reset();
     }
 
+    ~GrSamplerState() {
+        GrSafeUnref(fCustomStage);
+    }
+
     WrapMode getWrapX() const { return fWrapX; }
     WrapMode getWrapY() const { return fWrapY; }
     FilterDirection getFilterDirection() const { return fFilterDirection; }
@@ -188,6 +194,7 @@ public:
         fMatrix = matrix;
         fTextureDomain.setEmpty();
         fSwapRAndB = false;
+        GrSafeSetNull(fCustomStage);
     }
     void reset(WrapMode wrapXAndY, Filter filter, const GrMatrix& matrix) {
         this->reset(wrapXAndY, filter, kDefault_FilterDirection, matrix);
@@ -236,6 +243,11 @@ public:
         fKernelWidth = radius;
     }
 
+    void setCustomStage(GrCustomStage* stage) {
+        GrSafeAssign(fCustomStage, stage);
+    }
+    GrCustomStage* getCustomStage() const { return fCustomStage; }
+
 private:
     WrapMode            fWrapX : 8;
     WrapMode            fWrapY : 8;
@@ -246,6 +258,12 @@ private:
     bool                fSwapRAndB;
     GrRect              fTextureDomain;
 
+    /// BUG! Ganesh only works correctly so long as fCustomStage is  
+    /// NULL; we need to have a complex ID system here so that we can
+    /// have an equality-like comparison to determine whether two
+    /// fCustomStages are equal.
+    GrCustomStage*      fCustomStage;
+
     // these are undefined unless fSampleMode == kRadial2_SampleMode
     GrScalar            fRadial2CenterX1;
     GrScalar            fRadial2Radius0;