Add SkCanvas::writePixels that takes info+pixels directly

include/core/SkCanvas.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkCanvas_DEFINED
 #define SkCanvas_DEFINED
 
 #include "SkTypes.h"
 #include "SkBitmap.h"
 #include "SkDeque.h"
 #include "SkClipStack.h"
 #include "SkPaint.h"
 #include "SkRefCnt.h"
 #include "SkPath.h"
 #include "SkRegion.h"
 #include "SkXfermode.h"
 
+//#define SK_SUPPORT_LEGACY_WRITEPIXELSCONFIG
+
 class SkBounder;
 class SkBaseDevice;
 class SkDraw;
 class SkDrawFilter;
 class SkMetaData;
 class SkPicture;
 class SkRRect;
 class SkSurface;
 class SkSurface_Base;
 class GrContext;
@@ skipping 226 matching lines @@
                     Config8888 config8888 = kNative_Premul_Config8888);
 
     /**
      * DEPRECATED: This will be removed as soon as webkit is no longer relying
      * on it. The bitmap is resized to the intersection of srcRect and the
      * canvas bounds. New pixels are always allocated on success. Bitmap is
      * unmodified on failure.
      */
     bool readPixels(const SkIRect& srcRect, SkBitmap* bitmap);
 
+#ifdef SK_SUPPORT_LEGACY_WRITEPIXELSCONFIG
     /**
+     *  DEPRECATED
      *  Similar to draw sprite, this method will copy the pixels in bitmap onto
      *  the canvas, with the top/left corner specified by (x, y). The canvas'
      *  pixel values are completely replaced: there is no blending.
      *
      *  Currently if bitmap is backed by a texture this is a no-op. This may be
      *  relaxed in the future.
      *
      *  If the bitmap has config kARGB_8888_Config then the config8888 param
      *  will determines how the pixel valuess are intepreted. If the bitmap is
      *  not kARGB_8888_Config then this parameter is ignored.
      *
      *  Note: If you are recording drawing commands on this canvas to
      *  SkPicture, writePixels() is ignored!
      */
-    void writePixels(const SkBitmap& bitmap,
-                     int x, int y,
-                     Config8888 config8888 = kNative_Premul_Config8888);
+    void writePixels(const SkBitmap& bitmap, int x, int y, Config8888 config8888);
+#endif
+
+    /**
+     *  This method affects the pixels in the base-layer, and operates in pixel coordinates,
+     *  ignoring the matrix and clip.
+     *
+     *  The specified ImageInfo and (x,y) offset specifies a rectangle: target.
+     *
+     *      target.setXYWH(x, y, info.width(), info.height());
+     *
+     *  Target is intersected with the bounds of the base-layer. If this intersection is not empty,
+     *  then we have two sets of pixels (of equal size), the "src" specified by info+pixels+rowBytes
+     *  and the "dst" by the canvas' backend. Replace the dst pixels with the corresponding src
+     *  pixels, performing any colortype/alphatype transformations needed (in the case where the
+     *  src and dst have different colortypes or alphatypes).
+     *
+     *  This call can fail, returning false, for several reasons:
+     *  - If the src colortype/alphatype cannot be converted to the canvas' types
+     *  - If this canvas is not backed by pixels (e.g. picture or PDF)
+     */
+    bool writePixels(const SkImageInfo&, const void* pixels, size_t rowBytes, int x, int y);
+
+    /**
+     *  Helper for calling writePixels(info, ...) by passing its pixels and rowbytes. If the bitmap
+     *  is just wrapping a texture, returns false and does nothing.
+     */
+    bool writePixels(const SkBitmap& bitmap, int x, int y);
 
     ///////////////////////////////////////////////////////////////////////////
 
     enum SaveFlags {
         /** save the matrix state, restoring it on restore() */
         kMatrix_SaveFlag            = 0x01,
         /** save the clip state, restoring it on restore() */
         kClip_SaveFlag              = 0x02,
         /** the layer needs to support per-pixel alpha */
         kHasAlphaLayer_SaveFlag     = 0x04,
@@ skipping 1077 matching lines @@
     bool asROBitmap(SkBitmap*) const;
 
 private:
     SkBitmap    fBitmap;    // used if peekPixels() fails
     const void* fAddr;      // NULL on failure
     SkImageInfo fInfo;
     size_t      fRowBytes;
 };
 
 #endif