Rewriting to use CIImage in hopes of better performance. Still playing with p...

chrome/browser/cocoa/throbber_view.mm

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/cocoa/throbber_view.h"
 
 #include "base/logging.h"
 
 const float kAnimationIntervalSeconds = 0.03;  // 30ms, same as windows
 
@@ skipping 30 matching lines @@
   if ((self = [super initWithFrame:frame])) {
     // Ensure that the height divides evenly into the width. Cache the
     // number of frames in the animation for later.
     NSSize imageSize = [image size];
     DCHECK(imageSize.height && imageSize.width);
     if (!imageSize.height)
       return nil;
     DCHECK((int)imageSize.width % (int)imageSize.height == 0);
     numFrames_ = (int)imageSize.width / (int)imageSize.height;
     DCHECK(numFrames_);
-    image_.reset([image retain]);
+
+    // First check if we have a bitmap image rep and use it, otherwise fall
+    // back to creating one.
+    NSBitmapImageRep* rep = [[image representations] objectAtIndex:0];
+    if (![rep isKindOfClass:[NSBitmapImageRep class]]) {
+      [image lockFocus];
+      NSRect imageRect = NSMakeRect(0, 0, imageSize.width, imageSize.height);
+      rep = [[[NSBitmapImageRep alloc] initWithFocusedViewRect:imageRect]
+                autorelease];
+      [image unlockFocus];
+    }
+    image_.reset([[CIImage alloc] initWithBitmapImageRep:rep]);
 
     // Start a timer for the animation frames.
     target_.reset([[TimerTarget alloc] initWithThrobber:self]);
     timer_ =
         [NSTimer scheduledTimerWithTimeInterval:kAnimationIntervalSeconds
                                          target:target_.get()
                                        selector:@selector(animate:)
                                        userInfo:nil
                                         repeats:YES];
   }
   return self;
 }
 
 - (void)dealloc {
   [timer_ invalidate];
   [super dealloc];
 }
 
 - (void)removeFromSuperview {
   [timer_ invalidate];
   timer_ = nil;
 
   [super removeFromSuperview];
 }
 
 // Called when the TimerTarget gets tickled by our timer. Increment the frame
 // counter and mark as needing display.
 - (void)animate {
   animationFrame_ = ++animationFrame_ % numFrames_;
-  //[self setNeedsDisplay:YES];
+  [self setNeedsDisplay:YES];
 }
 
 // Overridden to draw the appropriate frame in the image strip.
 - (void)drawRect:(NSRect)rect {
-  float imageDimension = [image_ size].height;
+  float imageDimension = [image_ extent].size.height;
   float xOffset = animationFrame_ * imageDimension;
   NSRect sourceImageRect =
       NSMakeRect(xOffset, 0, imageDimension, imageDimension);
-  [image_ compositeToPoint:NSMakePoint(0, 0)
-                  fromRect:sourceImageRect
-                 operation:NSCompositeSourceOver];
+  [image_ drawInRect:[self bounds]
+             fromRect:sourceImageRect
+            operation:NSCompositeSourceOver
+             fraction:1.0];
 }
 
 @end