Is CoreGraphics (much) slower on the new iPad?

Question

I just got the new iPad(3) and currently testing out a high resolution version of my drawing app that uses CoreGraphics.

In normal 1024x768 mode, the iPad is more or less similar in performance - with only a slight lag when drawing quickly.

But when I try painting on a high resolution canvas (2048x1536) the app becomes unusably slow and laggy. Is this because CoreGraphics are mostly calculated by the CPU (which I believe is not that much faster than the iPad2) and has to do 4x more work?

I have basically changed my drawing routine from

UIGraphicsBeginImageContext(CGSizeMake(1024, 768));

To

UIGraphicsBeginImageContextWithOptions(CGSizeMake(1024, 768), NO, 0.0);

To enable retina drawing, and the lines are super nice and crisp and images are saved out in 2048x1536. But as mentioned, the delay and lag is making it useless as a drawing tool.

Apart from rewriting my app in openGL (Not an option due to time constraints and earlier unsuccessful attempts at a critical blending mode), is there anything I can do to optimize a CoreGraphics app running in retina mode on the new iPad?

Answer 1

If the app is made by you and makes ur iPad slow, you should run test on it over Instruments that is part of xcode. I think it can help you find out the problem. I don't think ur iPad has malfunction or something like that.