Open Radar

 
12-May-2012 07:47 AM Daniel Jalkut:
Starting in 10.7.4, some PNG images that were previously "fine" are drawing transparently, that is, as if they have no image content whatsoever.

I'm attaching three example images from the open source "TunesWindow" from Matt Gemmell, which demonstrate the problem. These images draw fine in 10.7.3 but in 10.7.4 they are shown transparent. They are also shown transparent in e.g. Quicklook and Preview, but if you open them in an app such as Acorn their content is visible.

The ramifications of this are great especially when such images are used to compose a user interface, as they are in TunesWindow, which is code that many different apps share.


12-May-2012 07:47 AM Daniel Jalkut:
'FlatTopImages.zip' was successfully uploaded

12-May-2012 07:53 AM Daniel Jalkut:
Nobody panic - I may be losing my mind :) Now the images are showing up fine in Preview. May have jumped to conclusions. Investigating.

11-May-2012 08:27 PM Daniel Jalkut:
OK - I am on to something changed in AppKit, but it's not what I first assumed. 

The attached project demonstrates that 

[topMiddle lockFocus];
NSColor *bgColor = NSReadPixel(NSMakePoint(0, 0));
[topMiddle unlockFocus];

Yields a nil color (even though the pixel is present), while:

[topMiddle lockFocus];
NSColor *bgColor = NSReadPixel(NSMakePoint(1, 1));
[topMiddle unlockFocus];

Yields a valid color.

The bug in this case actually is based not on inability to draw the specified images, but in failure to set up the background color for the window to match the images.


11-May-2012 08:27 PM Daniel Jalkut:
'NSGetColorTest.zip' was successfully uploaded