Initial picture shader implementation

src/core/SkPictureShader.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 SkPictureShader_DEFINED
+#define SkPictureShader_DEFINED
+
+#include "SkShader.h"
+
+class SkBitmap;
+class SkPicture;
+

[robertphillips, 2014/04/02 18:15:35]

// The SkPictureShader ...

[f(malita), 2014/04/07 15:06:24]

Done.

+class SkPictureShader : public SkShader {

[reed1, 2014/04/07 14:03:15]

Defensively, lets keep this private, and just expose a factory on SkPicture or
SkShader...?

[f(malita), 2014/04/07 15:06:24]

Done.

+public:
+    SkPictureShader(SkPicture*, TileMode, TileMode);
+    virtual ~SkPictureShader();
+
+    virtual bool setContext(const SkBitmap&, const SkPaint&, const SkMatrix&) SK_OVERRIDE;
+    virtual void endContext() SK_OVERRIDE;
+    virtual uint32_t getFlags() SK_OVERRIDE;
+
+    virtual ShadeProc asAShadeProc(void** ctx) SK_OVERRIDE;
+    virtual void shadeSpan(int x, int y, SkPMColor dstC[], int count) SK_OVERRIDE;
+    virtual void shadeSpan16(int x, int y, uint16_t dstC[], int count) SK_OVERRIDE;
+
+    SK_TO_STRING_OVERRIDE()
+    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPictureShader)
+
+#if SK_SUPPORT_GPU
+    GrEffectRef* asNewEffect(GrContext*, const SkPaint&) const SK_OVERRIDE;
+#endif
+
+protected:
+    SkPictureShader(SkReadBuffer&);
+    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
+
+private:
+    bool buildBitmapShader(const SkMatrix&) const;
+

[robertphillips, 2014/04/02 18:15:35]

this should go last.

[f(malita), 2014/04/07 15:06:24]

Done.

+    typedef SkShader INHERITED;
+
+    SkPicture*  fPicture;
+    TileMode    fTmx, fTmy;
+
+    mutable SkAutoTUnref<SkShader>  fCachedShader;
+    mutable SkSize                  fCachedTileScale;
+};
+
+#endif // SkPictureShader_DEFINED