Mailing Lists: Apple Mailing Lists
Image of Mac OS face in stamp
 
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Efficient drawing OpenGL vs. CoreImage


On May 20, 2006, at 1:27 PM, Federico Tessmann wrote:

For the animation task we use a timer with an interval of 0,02 seconds.
For drawing we bind each texture and then draw it. 


In both solutions the turntable views are juddering. The machine I was
testing on is a g4 powerbook with 1.5 GHz and 1.25 GB RAM. I have an
GeForce FX Go5200 graphics card with 64 MB VRAM.

What is genarally the better solution regarding performance? Would it
help to thread the drawing? If threading is reasonable how can I
guaranty that the drawing in seperate threads is save?
Furthermore I made the observation that OpenGL reacts a lot better to
mouse events than CoreImage, is there a logic behind that?

There is a good chance that your screen flushes are running afowl of the screen refresh mechanism on 10.4. On 10.4, if you explicitly flush one of your buffers and then try to draw to it again before the system has fully flushed it to the display then the system will block your application. Your timer interval of 50Hz sounds like it might be just close enough to the refresh rate of the monitor that it's giving you fits.

You might look into combining your OpenGL solution with Core Video. Core Video is the best bet you have for providing animation at a fixed refresh rate.

Scott

_______________________________________________
Do not post admin requests to the list. They will be ignored.
Quartz-dev mailing list      (email@hidden)
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/quartz-dev/email@hidden

This email sent to email@hidden
References: 
 >Efficient drawing OpenGL vs. CoreImage (From: "Federico Tessmann" <email@hidden>)



Visit the Apple Store online or at retail locations.
1-800-MY-APPLE

Contact Apple | Terms of Use | Privacy Policy

Copyright © 2007 Apple Inc. All rights reserved.