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View frustum culling doubt

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I was reading thru the tutorials at http://www.markmorley.com/opengl/frustumculling.html for view frustum culling and i have some doubt. Whats "MODELVIEW" glGetFloatv( GL_MODELVIEW_MATRIX, modl ); being described in the tutorial or whatz its equivalent in directx ? thanks a lot in advance... Slow and steady wins the race.

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Direct3D uses 3 main matrices for transformation*:

1. WORLD - the transformation from local object ("model") space into world space.

2. VIEW - the transformation from world space into camera/view space.

3. PROJECTION - the transformation from view space into homogenous clip space.


OpenGL uses 2 matrices:

1. MODELVIEW - the transformation from object ("model") space into camera/view space.

2. PROJECTION - as above.


So you should be able to guess that MODELVIEW is simply:

MODELVIEW = WORLD * VIEW


* D3D actually generates a few other matrices internally from the 3 you supply. There isn''t any direct way to get at those though

--
Simon O''Connor
Creative Asylum Ltd
www.creative-asylum.com

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I would like to know too: So can I substitute the OpenGL matricies with the just the D3D projection and view matrix? The points to test will already be transformed into world space

It wierd seeing OpenGL code, its so damn procedural. They don''t even use structs!!!

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