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View Full Version : multitexturing slowdown



JanHH
05-04-2003, 03:52 PM
Hello,

I have just added multitexturing (normal texture + lightmap) to my program, and it looks fine but it gets much slower (about 50% of the the former speed, I guess). As I use a gf 4 ti 4200 I thought it should be just as fast as with only one texture? Is there anything special one has to known? (I used glAcviteTextureARB(...), glMultiTexCoordARB(...) etc.).

Regards,
Jan

JanHH
05-04-2003, 05:31 PM
got it fixed. thx to anyone who would have answered http://www.opengl.org/discussion_boards/ubb/wink.gif.

Jan

M/\dm/\n
05-05-2003, 03:39 AM
You should check the optimal size of lightmap! I had 256x256 lightmaps & later I decided to check the optimal size. I added code that allowed me to import lightmaps of size 256x256, 128x128, 64x64, 32x32, 16x16, 8x8 and dinamycaly switch among them. After small test I found out that !!!!!!16x16!!!!!! are allmost identical to 256x256! 8x8 was noticably worse. But after remaking my lightmaps I got + 8-10 fps on GF2GTS in app that runs at ~26avg, so eliminating swapping to RAM I guess.
BTW, in some cases you could use 128x2 lightmaps somtimes 32x32 is needed.

JanHH
05-06-2003, 10:43 AM
at the moment there is only one large lightmap that covers the entire area and is about 10000 x 10000 texels, but the program does not seem to slow down at all with multitexturing enabled.

Jan

Poons
05-07-2003, 03:39 PM
i have the same problem with the frame rate.
maybe you could post your solution ??

thanx

JanHH
05-07-2003, 08:09 PM
i simply had too much opengl calls, i called glBindTexture... before every single texture coordinate passed. what is the problem with your program?

M/\dm/\n
05-08-2003, 01:09 AM
I had a lot 256x256 textures + cubemap 512x512*6 so on 32 MB GF2GTS it was bottleneck, now I have GFFX5200w128MB on table, I'll check what it'll change when I'll get home http://www.opengl.org/discussion_boards/ubb/biggrin.gif