WebCore/platform/chromium/DragImageChromiumMac.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/platform/chromium/DragImageChromiumMac.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2010, Google Inc. All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "DragImage.h"
+
+#include "Image.h"
+#include "NotImplemented.h"
+#include <wtf/RetainPtr.h>
+
+#include <CoreGraphics/CGBitmapContext.h>
+#include <CoreGraphics/CGImage.h>
+
+namespace WebCore {
+
+IntSize dragImageSize(DragImageRef image)
+{
+    if (!image)
+        return IntSize();
+    return IntSize(CGImageGetWidth(image), CGImageGetHeight(image));
+}
+
+void deleteDragImage(DragImageRef image)
+{
+    CGImageRelease(image);
+}
+
+DragImageRef scaleDragImage(DragImageRef image, FloatSize scale)
+{
+    if (!image)
+        return 0;
+    size_t width = roundf(CGImageGetWidth(image) * scale.width());
+    size_t height = roundf(CGImageGetHeight(image) * scale.height());
+
+    RetainPtr<CGColorSpaceRef> deviceRGB(WTF::AdoptCF, CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB));
+    CGContextRef context = CGBitmapContextCreate(0, width, height, 8, width * 4, deviceRGB.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host);
+
+    if (!context)
+        return 0;
+    CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
+    CGImageRelease(image);
+
+    CGImageRef scaledImage = CGBitmapContextCreateImage(context);
+    CGContextRelease(context);
+    return scaledImage;
+}
+
+DragImageRef dissolveDragImageToFraction(DragImageRef image, float delta)
+{
+    if (!image)
+        return 0;
+    size_t width = CGImageGetWidth(image);
+    size_t height = CGImageGetHeight(image);
+
+    RetainPtr<CGColorSpaceRef> deviceRGB(WTF::AdoptCF, CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB));
+    CGContextRef context = CGBitmapContextCreate(0, width, height, 8, width * 4, deviceRGB.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host);
+
+    if (!context)
+        return 0;
+    // From CGContext.h:
+    //     The Porter-Duff "source over" mode is called `kCGBlendModeNormal':
+    //       R = S + D*(1 - Sa)
+    //  This is the same as NSCompositeSourceOver, which is what -[NSImage dissolveToPoint:fraction:] uses.
+    CGContextSetAlpha(context, delta);
+    CGContextSetBlendMode(context, kCGBlendModeNormal);
+    CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
+    CGImageRelease(image);
+
+    CGImageRef dissolvedImage = CGBitmapContextCreateImage(context);
+    CGContextRelease(context);
+    return dissolvedImage;
+}
+
+DragImageRef createDragImageFromImage(Image* image)
+{
+    if (!image)
+        return 0;
+    return CGImageCreateCopy(image->nativeImageForCurrentFrame());
+}
+
+DragImageRef createDragImageIconForCachedImage(CachedImage*)
+{
+    notImplemented();
+    return 0;
+}
+
+} // namespace WebCore