Hi, How can I use the T&L ? ======================== Leyder Dylan http://ibelgique.ifrance.com/Slug-Production/

You are already using it. It''s automatic in OpenGL.

do you know what transformations and lighting are?

masterg, is that a question to anyone?

If yes, then (I suppose)

What I belive ''em to be are these....
(GPU stylee)
transformations=dealing with geometry
lighting=err, lighting
all done in hardware of course
Mmmm, speed

Although inOGL, tranformation = matrix transformations?

The transform part means that matrix math where you multiply the coordinate of a point(vertex) by the modelview matrix/transform matrix is done by hardware rather than the CPU. THis is an issue becuase games made before t&l built all that math into the game rather than leaving it to the driver to sort out. So even if you have a t&l card games that were designed around that kind of engine don''t take advantage of the hardware. The lighting part is self explanitory. The lighting part is generally useless becuase if you use more than one light the performance goes down the tube rather quickly.

The fanatic is incorruptible: if he kills for an idea, he can just as well get himself killed for one; in either case, tyrant or martyr, he is a monster.
--EM Cioran

Opere Citato

quote:

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Original post by Anonymous Poster
You are already using it. It''s automatic in OpenGL.

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Really? I thought you must use the extensions of the OpenGL drivers of the card...

no

quote:

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Original post by zedzeek
no

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Then how comes there are games such as MDK2 wich lets the user decide if he/she wants to use T&L at runtime?

If the game programmer has done some fancy maths to calculate things like rotations or lighting equations in their own code; then they won''t take advantage of T&L.

If however, they''ve used commands like glRotate or glTranslate rather than doing the calculations themselves, they will automatically use T&L if available.

The reason some games chose not to use glRotate etc is that the programmers could write their own optimised routines to do just what they wanted rather than all the extra crap they didn''t need from the built in gl functions. This means that if the system doesn''t have T&L capabilities it can use their (faster but not as wide ranging) functions instead. If it does, then the (slower but wider ranging) gl functions are hardware accelerated anyway so there''s no point writing optimised software functions.

Hope that clears it up.

Stephen