Convert CG images to Skia to draw.

Review URL: http://codereview.chromium.org/3088

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@2304 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 52 insertions, 0 deletions

diff --git a/webkit/glue/image_decoder.cc b/webkit/glue/image_decoder.cc
index e6c448b..577b3183 100644
--- a/webkit/glue/image_decoder.cc
+++ b/webkit/glue/image_decoder.cc
@@ -6,7 +6,12 @@
 #include "webkit/glue/image_decoder.h"
 
 #pragma warning(push, 0)
+#if defined(OS_WIN)
 #include "ImageSourceSkia.h"
+#elif defined(OS_MACOSX)
+#include "ImageSource.h"
+#include "RetainPtr.h"
+#endif
 #include "IntSize.h"
 #include "RefPtr.h"
 #include "SharedBuffer.h"
@@ -27,12 +32,28 @@ ImageDecoder::~ImageDecoder() {
 }
 
 SkBitmap ImageDecoder::Decode(const unsigned char* data, size_t size) {
+  
+  // What's going on here? ImageDecoder is only used by ImageResourceFetcher,
+  // which is only used (but extensively) by WebViewImpl. On the Mac we're using
+  // CoreGraphics, but right now WebViewImpl uses SkBitmaps everywhere. For now,
+  // this is a convenient bottleneck to convert from CGImageRefs to SkBitmaps,
+  // but in the future we will need to replumb to get CGImageRefs (or whatever
+  // the native type is) everywhere, directly.
+  
+#if defined(OS_WIN)
   WebCore::ImageSourceSkia source;
+#elif defined(OS_MACOSX)
+  WebCore::ImageSource source;
+#endif
   WTF::RefPtr<WebCore::SharedBuffer> buffer(new WebCore::SharedBuffer(
       data, static_cast<int>(size)));
+#if defined(OS_WIN)
   source.setData(buffer.get(), true,
                  WebCore::IntSize(desired_icon_size_.width(),
                                   desired_icon_size_.height()));
+#elif defined(OS_MACOSX)
+  source.setData(buffer.get(), true);
+#endif
 
   if (!source.isSizeAvailable())
     return SkBitmap();
@@ -41,7 +62,38 @@ SkBitmap ImageDecoder::Decode(const unsigned char* data, size_t size) {
   if (!frame0)
     return SkBitmap();
   
+#if defined(OS_WIN)
   return *reinterpret_cast<SkBitmap*>(frame0);
+#elif defined(OS_MACOSX)
+  // BitmapImage releases automatically, but we're bypassing it so we'll need
+  // to do the releasing.
+  RetainPtr<CGImageRef> image(AdoptCF, frame0);
+  
+  SkBitmap result;
+  result.setConfig(SkBitmap::kARGB_8888_Config, CGImageGetWidth(image.get()),
+                   CGImageGetHeight(image.get()));
+  
+  RetainPtr<CGColorSpace> cg_color(AdoptCF, CGColorSpaceCreateDeviceRGB());
+  // The last parameter is a total guess. Feel free to adjust it if images draw
+  // incorrectly. TODO(avi): Verify byte ordering; it should be possible to
+  // swizzle bytes with various combinations of the byte order and alpha
+  // constants.
+  RetainPtr<CGContextRef> context(AdoptCF, CGBitmapContextCreate(
+                                             result.getPixels(),
+                                             result.width(),
+                                             result.height(),
+                                             result.bytesPerPixel() * 8 / 4,
+                                             result.rowBytes(),
+                                             cg_color.get(),
+                                             kCGImageAlphaPremultipliedFirst |
+                                             kCGBitmapByteOrder32Host));
+  CGRect rect = CGRectMake(0, 0,
+                           CGImageGetWidth(image.get()),
+                           CGImageGetHeight(image.get()));
+  CGContextDrawImage(context.get(), rect, image.get());
+  
+  return result;
+#endif
 }
 
 }  // namespace webkit_glue