Implementing filling for SkBmpCodec

src/codec/SkSwizzler.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkSwizzler_DEFINED
 #define SkSwizzler_DEFINED
 
@@ skipping 136 matching lines @@
      * A NULL colorTable means colorOrIndex is treated as an SkPMColor (premul or
      * unpremul, depending on dstInfo.alphaType()). Each 4-byte pixel will be set to
      * colorOrIndex.
 
      * A non-NULL colorTable means colorOrIndex is treated as a uint8_t index into
      * the colorTable. i.e. each 4-byte pixel will be set to
      * colorTable[(uint8_t) colorOrIndex].
      *
      * Other SkColorTypes are not supported.
      *
+     * @param bottomUp
+     * If true, this indicates that stream contains rows of the image starting from the
+     * bottom.  The rows that need to be filled will be the top rows.
+     *
      */
     static void Fill(void* dst, const SkImageInfo& dstInfo, size_t dstRowBytes, uint32_t y,
-            uint32_t colorOrIndex, SkPMColor* colorTable);
+            uint32_t colorOrIndex, const SkPMColor* colorTable, bool bottomUp = false);

[scroggo, 2015/04/10 18:12:43]

I think it would be better to use RowOrder (which may need to move somewhere
common).

[msarett, 2015/04/10 20:52:56]

A new design will take care of this.  We will now pass in the dstStartRow and
the number of rows to fill.

 
     /**
      *  Swizzle the next line. Call height times, once for each row of source.
      *  @param src The next row of the source data.
      *  @return A result code describing if the row was fully opaque, fully
      *          transparent, or neither
      */
     ResultAlpha next(const uint8_t* SK_RESTRICT src);
 
     /**
@@ skipping 58 matching lines @@
     const SkImageInfo   fDstInfo;
     void*               fDstRow;
     const size_t        fDstRowBytes;
     int                 fCurrY;
 
     SkSwizzler(RowProc proc, const SkPMColor* ctable, int deltaSrc,
                const SkImageInfo& info, void* dst, size_t rowBytes);
 
 };
 #endif // SkSwizzler_DEFINED