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VSync in 2700G chip

PostPosted: Mar 1, 2006 @ 10:47am
by hamster
Hi! :D

I'm writing a 2D program using PowerVR MBX (the 'lite' release?) and I'm surprised about the slow execution of my program despite the simplicity of it. I think (but I'm not sure) that the main problem could be the vsync, I has read that I could disable vsync using eglSwapInterval, but this function is not available for the PowerVR release that I'm using... Are there any other possibility to disable vsync? Is really so slow to change a texture bitmap using glTexSubImage2D with the 2700G chip? Exist any other OpenGLES implementation instead of PowerVR that supports Dell Axim acceleration?

Thanks!

PostPosted: Mar 3, 2006 @ 9:05am
by hamster

PostPosted: Mar 3, 2006 @ 3:27pm
by Dan East

PostPosted: Mar 4, 2006 @ 3:20am
by hamster

PostPosted: Mar 4, 2006 @ 8:42am
by rcp
PowerVR has two compressed texture formats. These can be stored directly into memory, and thus the download time is very fast. If your images are static, you can use this format. If your images are not, you can use RGB565. If you are seeing slow download times, it is probably because you are using a format or size that doesn't fit. ie; the texture size must be a power of 2, you can't download sub-images, things must fit RGB565 or one of the compressed formats.
While texture download is slow, it is not that slow (37ms). We play movies using a 256x256 RGB565 texture and it plays at 30fps with plenty of time to spare. If you would like, you can post your download code and I will look to see if I see any performance problems.

PostPosted: Mar 8, 2006 @ 10:17pm
by joshbu [MSFT]

PostPosted: May 31, 2006 @ 9:08pm
by Tala