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View Full Version : Thougts on Texture Compression


bagman
11-13-04, 06:29 PM
Hi guys
Can yu assist in clearing up my understanding on Texture Compression ?
My (limited) understanding is that by enabling texture compression a given amount of texture data can be stored using significantly less memory.
In other words, the on-board memory of the graphics card is used thus freeing up system memory ??? Less pressure on AGP bus bandwidths ??
Would it follow then that decreased memory/bandwith requirements = increased performance & better image quality ??
I seem to recall reading somewhere that texture compression can allow for larger textures, therefore more surface detail ?? Additionally texture compression can also allow for a greater variety of textures to be used at any given time, permitting more varied scenes ??

Is my thinking correct on this subject ?? Provided the on-board memory of yur video card is sufficiently high ( in my case 256mb with my 6800GT ) texture compression should be enabled in most games ??
What effects does texture compression have on mip-mapping ??

Appreciate you pointing out if I am wrong in any of my thoughts and also any additional info or tips yu can provide

cheers
Bagman

subbo
11-13-04, 07:32 PM
These days most games use the .DDS format that combines everything from various levels/versions of DirectX texture compression, alpha channels, pre-calculated mipmaps, bumpmaps, pixel shaders and more.

So yes todays games use texture compression and have for a long time. We are already enjoying the benefits of compression to speed up our games, and games like Painkiller use it to good effect.. though in some ways overdo it (shadows can show compression artifacts and colored blotches).

In the past a 1024x1024 .tga .tiff or even .bmp would take megabytes of ram, today it can take as little as a few hundred kb.