Band-aid for subsetted bitmaps in SKPs.

src/core/SkOrderedReadBuffer.cpp

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkErrorInternals.h"
@@ skipping 179 matching lines @@
                                        "SkOrderedReadBuffer has no SkBitmapHeapReader to "
                                        "retrieve the SkBitmap.");
         }
     } else {
         // The writer stored false, meaning the SkBitmap was not stored in an SkBitmapHeap.
         const size_t length = this->readUInt();
         if (length > 0) {
             // A non-zero size means the SkBitmap was encoded.
             const void* data = this->skip(length);
             if (fBitmapDecoder != NULL && fBitmapDecoder(data, length, bitmap)) {
-                SkASSERT(bitmap->width() == width && bitmap->height() == height);
-                return;
+                if (bitmap->width() == width && bitmap->height() == height) {
+                    return;
+                }
+
+                // This case can only be reached if extractSubset was called, so
+                // the recorded width and height must be smaller than (or equal to
+                // the encoded width and height.
+                SkASSERT(width <= bitmap->width() && height <= bitmap->height());
+
+                // FIXME: Once the writer is changed to record the (x,y) offset,
+                // they will be used to store the correct portion of the picture.
+                SkBitmap subsetBm;
+                SkIRect subset = SkIRect::MakeWH(width, height);
+                if (bitmap->extractSubset(&subsetBm, subset)) {
+                    bitmap->swap(subsetBm);
+                    return;
+                }
             }
             // This bitmap was encoded when written, but we are unable to decode, possibly due to
             // not having a decoder.
             SkErrorInternals::SetError(kParseError_SkError,
                                        "Could not decode bitmap. Resulting bitmap will be red.");
         } else {
             // A size of zero means the SkBitmap was simply flattened.
             bitmap->unflatten(*this);
             return;
         }
@@ skipping 55 matching lines @@
         if (sizeRecorded != sizeRead) {
             // we could try to fix up the offset...
             sk_throw();
         }
     } else {
         // we must skip the remaining data
         fReader.skip(sizeRecorded);
     }
     return obj;
 }