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czar
29-03-2005, 10:36 AM
I ran into a few problems when I found that my program wouldn't even work on graphics cards with 32 megabytes of graphic memory. :roll:

So I downsized my textures and reduced colour depth and now everything is sweet. My question is..

How are textures stored in the video memory of a graphics card?

if Photoshop says my picture is say 256k and the picture has 8 bit colour depth does that mean it will also only take 256k in video memory or is everything multiplied by 4 and stored as full RGB + alpha?


Does it makes sense to load bitmaps into video memory that have 4 bit colour depth. I can reduce a number of my textures to 16 colours withoutr apparent visual loss, but is it wortyh the effort.

JSoftware
29-03-2005, 11:39 AM
If you haven't done it then implement texture compression. IIRC then textures are stored uncompressed as RGBA in texture memory

Regards Jeppe

Clootie
29-03-2005, 07:01 PM
Modern cards don't support paletted textures. If you want to compress textures use DXTx / S3TC compression

czar
29-03-2005, 07:54 PM
So what you are saying is that unless they are compressed I may as well leave textures in RGBA format?

Ok thanks.

Is there a utility available that displays how much video memory is used by an application? I am sure I have seen one nefore but I cannot rediscover where/what it is.

Clootie
29-03-2005, 07:59 PM
some versions of NVIDIA PerfHood supports it (for NV cards only)