Add GrAAHairLinePathRenderer

Review URL: http://codereview.appspot.com/4926045



git-svn-id: http://skia.googlecode.com/svn/trunk@2196 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/src/GrAAHairLinePathRenderer.h b/gpu/src/GrAAHairLinePathRenderer.h
new file mode 100644
index 0000000..c7d2dc7
--- /dev/null
+++ b/gpu/src/GrAAHairLinePathRenderer.h
@@ -0,0 +1,62 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrAAHairLinePathRenderer_DEFINED
+#define GrAAHairLinePathRenderer_DEFINED
+
+#include "GrPathRenderer.h"
+
+class GrAAHairLinePathRenderer : public GrPathRenderer {
+public:
+    virtual ~GrAAHairLinePathRenderer();
+
+    static GrPathRenderer* Create(GrContext* context);
+    // GrPathRenderer overrides
+    virtual bool supportsAA(GrDrawTarget* target,
+                            const SkPath& path,
+                            GrPathFill fill);
+    virtual bool canDrawPath(const GrDrawTarget* target,
+                             const SkPath& path,
+                             GrPathFill fill) const;
+    virtual void drawPath(GrDrawTarget::StageBitfield stages);
+
+protected:
+
+    // GrPathRenderer overrides
+    virtual void pathWillClear();
+
+private:
+    void resetGeom();
+
+    static bool CanBeUsed(const GrContext* context);
+    GrAAHairLinePathRenderer(const GrContext* context,
+                             const GrIndexBuffer* fLinesIndexBuffer,
+                             const GrIndexBuffer* fQuadsIndexBuffer);
+
+    bool createGeom(GrDrawTarget::StageBitfield stages);
+
+    GrContext*                  fContext;
+    const GrIndexBuffer*        fLinesIndexBuffer;
+    const GrIndexBuffer*        fQuadsIndexBuffer;
+
+    // have to recreate geometry if stages in use changes :(
+    GrDrawTarget::StageBitfield fPreviousStages;
+    int                         fPreviousRTHeight;
+    GrIRect                     fClipRect;
+
+    // this path renderer draws everything in device coordinates
+    GrMatrix                    fPreviousViewMatrix;
+    int                         fLineSegmentCnt;
+    int                         fQuadCnt;
+
+    typedef GrPathRenderer INHERITED;
+};
+
+
+#endif
+