store SkAlphaType inside SkBitmap, on road to support unpremul

src/images/SkImageRef.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkImageRef.h"
 #include "SkBitmap.h"
 #include "SkFlattenableBuffers.h"
@@ skipping 43 matching lines @@
         return false;
     }
 
     SkASSERT(SkBitmap::kNo_Config != fBitmap.config());
     if (bitmap) {
         bitmap->setConfig(fBitmap.config(), fBitmap.width(), fBitmap.height());
     }
     return true;
 }
 
 bool SkImageRef::isOpaque(SkBitmap* bitmap) {

[scroggo, 2013/10/18 19:32:40]

Doesn't necessarily need to be fixed here, but looking at the header, this
function does not return what it claims to be returning. This will may return
true even if fBitmap is not opaque. (I don't think anyone actually looks at the
return value, though.)

     if (bitmap && bitmap->pixelRef() == this) {
         bitmap->lockPixels();
-        bitmap->setIsOpaque(fBitmap.isOpaque());
+        // what about colortables??????

[scroggo, 2013/10/18 19:32:40]

Didn't you make colortables immutable so that you would not need to lock and
unlock? I think just checking fBitmap should be fine.

+        bitmap->setAlphaType(fBitmap.alphaType());
         bitmap->unlockPixels();
         return true;
     }
     return false;
 }
 
 SkImageDecoderFactory* SkImageRef::setDecoderFactory(
                                                 SkImageDecoderFactory* fact) {
     SkRefCnt_SafeAssign(fFactory, fact);
     return fact;
@@ skipping 114 matching lines @@
     // now.
     if (!fStream->rewind()) {
         SkDEBUGF(("Failed to rewind SkImageRef stream!"));
         buffer.write32(0);
     } else {
         // FIXME: Handle getLength properly here. Perhaps this class should
         // take an SkStreamAsset.
         buffer.writeStream(fStream, fStream->getLength());
     }
 }