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View Full Version : How do textures effect performance?


smally
25th May 2001, 11:24 AM
I was wondering if texture use effects performance? For instance if you made 2 maps completely identical in size, geometry, lighting etc. And the only difference between the 2 was the textures you used, let's say map #1 used 20 different textures out of 2 different texture packages and map #2 Used 200 different textures out of all of the different texture packs. Ok, so would map #1 run better or would there be little difference.

My thinking is that map #2 would run worse because your system would have to load all 200 of those textures into memory therefore hogging up all your ram, and if you didn't even have enough ram for all the textures then it would have to use virtual memory on the hard drive which would really blow performance. Although I wouldn't think the # of packages you pulled your textures from would matter that much (i.e. lets say you made map #3 with 20 textures but used those 20 tex's out of 20 different packages), I would think that wouldn't really hurt performance [or would UT have to load the entire package into memory just to use 1 texture out of the pack?(In which case it would screw up performance I guess)].

Anyway I don't really know. So if somebody does know could you explain the effects of texture usage on system performance to me? And if you're knowledgable enough tell me how much is too much? And any kind of general rules to follow in texture usage would be helpful.

Thanx for taking the time to read this overly long & boring post ;)

Mind Maze
25th May 2001, 03:05 PM
I just know about animated (water, lava, whatever) textures. Put a extremely large one and ur map will bog down any high-end PC.

Zurg
25th May 2001, 04:28 PM
Fom my inderstanding it is the size of the texture that will effect preformance. i.e. 128X128 is standard (I think).


The amount of colors detail in a texture is not relevant (I think).
I am not talking about polys either.

ChrisToth.hu
25th May 2001, 04:49 PM
THe number of visible palettes is very important. Fewer palettes can help framerates...

Euphoric Beaver
26th May 2001, 03:41 AM
What do you mean by palettes?

ChrisToth.hu
26th May 2001, 09:06 AM
The Unreal engine uses 8-bit textures...
A texture can contain 255 color and 1 masked palette value. (2 to the power of 8 = 256)

For example, if you have a 128x128 texture that means that it has a total 16384 pixels. You can put any of the 255 colors of the texture's palette into each pixel, or you can make some pixels masked if you use the color which is in the 0 value of the palette.

Now, if there are many textures visible in a scene, more time will be needed for your gfx card to load them in. If some of them use the same palette, this time will be decreased.

Thats it...