View Full Version : Projective Texturing in OpenGL

01-16-2002, 09:52 PM
Hello reader!!
I have asked many times, in this forum, how i can make shadows and multitexturing with my old Viper 330, and i haven't got a complete answer to my problem.
After months of searching i have found a demo talking about FAKE multitexturing and lightmaps. And voila, my Riva128 can render lighmaps.
Now the problem is somewhere else. Where can i find a tutorial or any kind of DETAILED resource on Projective Texturing using OpenGL??? I have download a demo from somewhere (i don't remember where) that illustrates exactly this thing. BUT the code was a little comfusing and because i don't want to use something that i don't understand, i would like to know if there is anything talking about Projective texturing in detail.
I read from time to time in some "non-OpenGL specific papers" that with projective texturing you can make shadows for static objects in initialization and that you can make real-time lighting effects with lightmaps and projective texturing. That's why i am asking for a tutorial.

Thanks in advance.


PS.: By the way can anyone suggest a better than Riva 128 card in PCI slot. You see, i have and old machine and i don't have AGP. Any suggestion accepted.

Thanks again.

01-16-2002, 10:24 PM
To your second question:

I have also an old machine and use PCI version of TNT2 m64. Works fine.

01-17-2002, 05:49 AM
There's a perspective texture projection example with code here: http://www.r3.nu/

And GeForce2 MX's come in PCI versions - you could probably find one for $100 or less.


01-17-2002, 11:08 PM
Hello again.
Thanks for the card suggestions.
To j:
The demo you are mensioned above is one of the two i found in the web about projective texturing in OpenGL. I have a little problem with them. There are not "very" clear. As i mentioned above i am asking for something detailed. In this specific demo, i tried to make it simple (If you have saw it you can understand it is very comfusing. Custom funcs calling custom funcs that call custom funcs and finally they call OpenGL funcs. you must track down every function and find out what OpenGL stuff is hidden behind it), by rewriting the code with only OpenGL functions (pure code). But the "project" failed sometime.
So, i am asking for something more detailed.If not a tutorial, then a more clean and commented piece of code.

Thanks again.