add new readPixels with direct memory parameters

include/core/SkDevice.h

 
 /*
  * Copyright 2010 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 SkDevice_DEFINED
@@ skipping 269 matching lines @@
                               const SkPoint verts[], const SkPoint texs[],
                               const SkColor colors[], SkXfermode* xmode,
                               const uint16_t indices[], int indexCount,
                               const SkPaint& paint) = 0;
     /** The SkDevice passed will be an SkDevice which was returned by a call to
         onCreateDevice on this device with kSaveLayer_Usage.
      */
     virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
                             const SkPaint&) = 0;
 
+#ifdef SK_SUPPORT_LEGACY_READPIXELSCONFIG
     /**
      *  On success (returns true), copy the device pixels into the bitmap.
      *  On failure, the bitmap parameter is left unchanged and false is
      *  returned.
      *
      *  The device's pixels are converted to the bitmap's config. The only
      *  supported config is kARGB_8888_Config, though this is likely to be
      *  relaxed in  the future. The meaning of config kARGB_8888_Config is
      *  modified by the enum param config8888. The default value interprets
      *  kARGB_8888_Config as SkPMColor
@@ skipping 10 matching lines @@
      *
      *  Other failure conditions:
      *    * If the device is not a raster device (e.g. PDF) then readPixels will
      *      fail.
      *    * If bitmap is texture-backed then readPixels will fail. (This may be
      *      relaxed in the future.)
      */
     bool readPixels(SkBitmap* bitmap,
                     int x, int y,
                     SkCanvas::Config8888 config8888);
+#endif
+    bool readPixels(const SkImageInfo&, void* dst, size_t rowBytes, int x, int y);
 
     ///////////////////////////////////////////////////////////////////////////
 
     /** Update as needed the pixel value in the bitmap, so that the caller can
         access the pixels directly.
         @return The device contents as a bitmap
     */
     virtual const SkBitmap& onAccessBitmap() = 0;
 
     /** Called when this device is installed into a Canvas. Balanced by a call
@@ skipping 35 matching lines @@
     static const SkCanvas::Config8888 kPMColorAlias;
 
 protected:
     // default impl returns NULL
     virtual SkSurface* newSurface(const SkImageInfo&);
 
     // default impl returns NULL
     virtual const void* peekPixels(SkImageInfo*, size_t* rowBytes);
 
     /**
      * Implements readPixels API. The caller will ensure that:

[scroggo, 2014/03/24 15:31:36]

Is this comment intended to apply to the new onReadPixels?

If so, it needs to be updated. Otherwise it should go inside the #ifdef

[reed1, 2014/03/24 15:53:05]

good point -- I'll move the comment into the ifdef

      *  1. bitmap has pixel config kARGB_8888_Config.
      *  2. bitmap has pixels.
      *  3. The rectangle (x, y, x + bitmap->width(), y + bitmap->height()) is
      *     contained in the device bounds.
      */
-    virtual bool onReadPixels(const SkBitmap& bitmap,
-                              int x, int y,
-                              SkCanvas::Config8888 config8888);
+#ifdef SK_SUPPORT_LEGACY_READPIXELSCONFIG
+    virtual bool onReadPixels(const SkBitmap& bitmap, int x, int y, SkCanvas::Config8888);
+#endif
+
+    /**
+     *  The caller is responsible for "pre-clipping" the dst. The impl can assume that the dst
+     *  image at the specified x,y offset will fit within the device's bounds.
+     *
+     *  This is explicitly asserted in readPixels(), the public way to call this.
+     */
+    virtual bool onReadPixels(const SkImageInfo&, void*, size_t, int x, int y);
 
     /**
      *  The caller is responsible for "pre-clipping" the src. The impl can assume that the src
      *  image at the specified x,y offset will fit within the device's bounds.
      *
      *  This is explicitly asserted in writePixelsDirect(), the public way to call this.
      */
     virtual bool onWritePixels(const SkImageInfo&, const void*, size_t, int x, int y);
 
     /**
@@ skipping 73 matching lines @@
     SkMetaData* fMetaData;
 
 #ifdef SK_DEBUG
     bool        fAttachedToCanvas;
 #endif
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif