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OpenGL Precompiled lightmaps in OpenGL

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Sid_Marcus    122
The question is: How to store a lightmap? As a matrix? Then building the surface is needed. As an image? Then how? In D3D everything was simple - I drew lightmaps on a DD surface, which was a texture. How to do it in OGL?

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Crash_Kid    122
In OpenGL it is exactly the same!
The LightMap is stored as an Image,
then you build a texture form the Lightmap-Image,
and draw it onto a Quad or something.

For the ''Light''-Effect you have to use Multitexturing...

Hope this helps...

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inolen    122
I got a question too. I got the multi-texturing of my lightmap working, but then how do I "disable" the multi texturing effect so I can go back to normal texturing.

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Crash_Kid    122

1. you choose the ''Texturechannel" with the lightmaps
2. glDisable(GL_TEXTURE_2D);

When you want to disable something in multitexturing,
choose the TMU and then use glDisable.

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inolen    122
Err. I mean heres the scenario.
Enable Texture0 Multi stuff( world texture ).
Enable Texture1 Multi stuff( lm texture ).
Draw them.
Now I want to draw my console like I always have, but the multi texture code is still going through and messing up my console.

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zedzeek    529
with gl if u turn something on it stays on until u turn it off

glActiveTexture( GL_TEXTURE1_ARB );
glEnable( GL_TEXTURE_2D );
.. texture unit 1 is now on to turn it off + to only use texture unit0 use

glActiveTexture( GL_TEXTURE1_ARB );
.. texture unit1 is now the one to be acted upon thus any code following will act on this unit, ie to disable it go
glDisable( GL_TEXTURE_2D );
glActiveTexture( GL_TEXTURE0_ARB );
.. unit 0 is now the active one

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