Properly use data when creating a bitmap platform canvas. Gets things painting

on the screen again.  Regressed in r18363.
Review URL: http://codereview.chromium.org/126140

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18415 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 60 insertions, 37 deletions

diff --git a/skia/ext/bitmap_platform_device_mac.cc b/skia/ext/bitmap_platform_device_mac.cc
index 79c735a..2daf772 100644
--- a/skia/ext/bitmap_platform_device_mac.cc
+++ b/skia/ext/bitmap_platform_device_mac.cc
@@ -44,6 +44,28 @@ bool Constrain(int available_size, int* position, int *size) {
   return true;
 }
 
+static CGContextRef CGContextForData(void* data, int width, int height) {
+  CGColorSpaceRef color_space =
+      CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
+  // Allocate a bitmap context with 4 components per pixel (BGRA).  Apple
+  // recommends these flags for improved CG performance.
+  CGContextRef context =
+      CGBitmapContextCreate(data, width, height, 8, width * 4,
+                            color_space,
+                            kCGImageAlphaPremultipliedFirst |
+                                kCGBitmapByteOrder32Host);
+  CGColorSpaceRelease(color_space);
+
+  if (!context)
+    return NULL;
+
+  // Change the coordinate system to match WebCore's
+  CGContextTranslateCTM(context, 0, height);
+  CGContextScaleCTM(context, 1.0, -1.0);
+
+  return context;
+}
+
 }  // namespace
 
 class BitmapPlatformDevice::BitmapPlatformDeviceData : public SkRefCnt {
@@ -153,15 +175,20 @@ void BitmapPlatformDevice::BitmapPlatformDeviceData::LoadConfig() {
 // that we can create the pixel data before calling the constructor. This is
 // required so that we can call the base class' constructor with the pixel
 // data.
-BitmapPlatformDevice* BitmapPlatformDevice::Create(CGContextRef context,
-                                                   int width,
-                                                   int height,
-                                                   bool is_opaque) {
+BitmapPlatformDevice* BitmapPlatformDevice::CreateWithContext(
+    CGContextRef context, int width, int height, bool is_opaque) {
   SkBitmap bitmap;
   bitmap.setConfig(SkBitmap::kARGB_8888_Config, width, height);
   if (bitmap.allocPixels() != true)
     return NULL;
-  void* data = bitmap.getPixels();
+
+  void* data = NULL;
+  if (context) {
+    data = CGBitmapContextGetData(context);
+    bitmap.setPixels(data);
+  } else {
+    data = bitmap.getPixels();
+  }
 
   // Note: The Windows implementation clears the Bitmap later on.
   // This bears mentioning since removal of this line makes the
@@ -170,36 +197,33 @@ BitmapPlatformDevice* BitmapPlatformDevice::Create(CGContextRef context,
 
   bitmap.setIsOpaque(is_opaque);
 
-  if (is_opaque) {
 #ifndef NDEBUG
+  if (is_opaque) {
     // To aid in finding bugs, we set the background color to something
     // obviously wrong so it will be noticable when it is not cleared
     bitmap.eraseARGB(255, 0, 255, 128);  // bright bluish green
-#endif
   }
+#endif
 
-  if (!context) {
-    CGColorSpaceRef color_space =
-      CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
-    // allocate a bitmap context with 4 components per pixel (BGRA). Apple
-    // recommends these flags for improved CG performance.
-    context =
-      CGBitmapContextCreate(data, width, height, 8, width*4,
-                            color_space,
-                            kCGImageAlphaPremultipliedFirst |
-                                kCGBitmapByteOrder32Host);
-
-    // Change the coordinate system to match WebCore's
-    CGContextTranslateCTM(context, 0, height);
-    CGContextScaleCTM(context, 1.0, -1.0);
-    CGColorSpaceRelease(color_space);
-  }
+  if (!context)
+    context = CGContextForData(data, width, height);
 
   // The device object will take ownership of the graphics context.
   return new BitmapPlatformDevice(
       new BitmapPlatformDeviceData(context), bitmap);
 }
 
+BitmapPlatformDevice* BitmapPlatformDevice::CreateWithData(uint8_t* data,
+                                                           int width,
+                                                           int height,
+                                                           bool is_opaque) {
+  CGContextRef context = NULL;
+  if (data)
+    context = CGContextForData(data, width, height);
+
+  return CreateWithContext(context, width, height, is_opaque);
+}
+
 // The device will own the bitmap, which corresponds to also owning the pixel
 // data. Therefore, we do not transfer ownership to the SkDevice's bitmap.
 BitmapPlatformDevice::BitmapPlatformDevice(
diff --git a/skia/ext/bitmap_platform_device_mac.h b/skia/ext/bitmap_platform_device_mac.h
index 6580302..d293cd4 100644
--- a/skia/ext/bitmap_platform_device_mac.h
+++ b/skia/ext/bitmap_platform_device_mac.h
@@ -25,17 +25,15 @@ namespace skia {
 // DEVICE'S PIXEL DATA TO ANOTHER BITMAP, make sure you copy instead.
 class BitmapPlatformDevice : public PlatformDevice {
  public:
-  // Factory function. The screen DC is used to create the bitmap, and will not
-  // be stored beyond this function. is_opaque should be set if the caller
-  // knows the bitmap will be completely opaque and allows some optimizations.
-  //
-  // The shared_section parameter is optional (pass NULL for default behavior).
-  // If shared_section is non-null, then it must be a handle to a file-mapping
-  // object returned by CreateFileMapping.  See CreateDIBSection for details.
-  static BitmapPlatformDevice* Create(CGContextRef context,
-                                      int width,
-                                      int height,
-                                      bool is_opaque);
+  // |context| may be NULL.
+  static BitmapPlatformDevice* CreateWithContext(CGContextRef context,
+                                                 int width, int height,
+                                                 bool is_opaque);
+
+  // Creates a context for |data| and calls CreateWithContext.
+  static BitmapPlatformDevice* CreateWithData(uint8_t* data,
+                                              int width, int height,
+                                              bool is_opaque);
 
   // Copy constructor. When copied, devices duplicate their internal data, so
   // stay linked. This is because their implementation is very heavyweight
diff --git a/skia/ext/platform_canvas_mac.cc b/skia/ext/platform_canvas_mac.cc
index 4e42bb1..e75e55aa 100644
--- a/skia/ext/platform_canvas_mac.cc
+++ b/skia/ext/platform_canvas_mac.cc
@@ -40,8 +40,8 @@ bool PlatformCanvas::initialize(int width,
                                 int height,
                                 bool is_opaque,
                                 uint8_t* data) {
-  SkDevice* device = BitmapPlatformDevice::Create(NULL, width, height,
-                                                  is_opaque);
+  SkDevice* device = BitmapPlatformDevice::CreateWithData(data, width, height,
+                                                          is_opaque);
   if (!device)
     return false;
 
@@ -63,7 +63,8 @@ SkDevice* PlatformCanvas::createDevice(SkBitmap::Config config,
                                        int height,
                                        bool is_opaque, bool isForLayer) {
   SkASSERT(config == SkBitmap::kARGB_8888_Config);
-  return BitmapPlatformDevice::Create(NULL, width, height, is_opaque);
+  return BitmapPlatformDevice::CreateWithContext(NULL, width, height,
+                                                 is_opaque);
 }
 
 }  // namespace skia