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JimmyT
06-12-2002, 06:02 AM
Is there a maximum size for vertex arrays?
If so, is there an OpenGL function that returns it? I have looked at all the documentation but cannot find anything.

I'm asking this because the maximum number of vertices I ssem able to render is about 2500, and this number decreases further if colour and/or normal arrays are also enabled. If I exceed this number I get an error in the driver library.

Thanks.

Robbo
06-12-2002, 06:29 AM
What graphics card are you using? 2,500 sounds awfully low - perhaps there is something else going on here.

JimmyT
06-12-2002, 06:50 AM
I'm using a Radeon 7500 (old, but not that ancient!) with 64mb.

Yeah, I thought 2500 was low too, but for the life of me I can't think of a good explanation. I'm not using any stride in my arrays, and I'm using a single call to glDrawElements to render.

Also, if anyone knows of an example using ATI_ARRAY_OBJECT I'd be very grateful, I can't make that work at all!

Thanks in advance.

hkyProgrammer88
06-12-2002, 09:01 PM
Are you sure that you calculated the size of your arrays (vertex, color, normal) correctly. I came up with a similar problem you had, and I found that after 370 verticies glDrawElements would crash. It took me a long time to determine that the sizes of my arrays were calculated wrong.

For a quick error detection, make all your arrays, (vertex, color and normal) larger than you need and see if the maximum is still 2500.

hkyProgrammer88
06-12-2002, 09:05 PM
Oh ya, also check your index array to see if it tries to index a vertex higher then vertex 2500.

Hope this helps.

zed
06-12-2002, 09:30 PM
it sounds like a problem with your code
btw for a gf/tnt for optimal speed 4096 verts indices (or less) is recommended, u can use more but performance will not be optimzal

JimmyT
06-12-2002, 11:29 PM
Thanks for the help guys! it probably is a problem with my code somewhere, guess I'll just have to keep fiddling with it.

Cheers.