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Lucretia
04-09-2002, 02:46 AM
Hi,

I was just wondering if there is an OpenGL specific extension (hw accelerated) that is eqivalent to D3D's matrix palettes?

Thanks,
Luke.

harsman
04-09-2002, 05:48 AM
ARB_vertex_blend (http://oss.sgi.com/projects/ogl-sample/registry/ARB/vertex_blend.txt)

jwatte
04-09-2002, 12:33 PM
ARB_vertex_blend is not quite the same, as each vert needs to have one weight for each enabled matrix. This quickly explodes in size, and/or forces you to cut your model in many itty-bitty buffers.

The only way to get real "N out of M" matrix palettes is to use NV_vertex_program and ATI_vertex_shader, respectively. Clearly, OGL2.0 would let you do this and much more with its standardized programmable pipeline.

Humus
04-09-2002, 04:06 PM
Originally posted by Lucretia:
Hi,

I was just wondering if there is an OpenGL specific extension (hw accelerated) that is eqivalent to D3D's matrix palettes?

Thanks,
Luke.

GL_ARB_matrix_palette (http://oss.sgi.com/projects/ogl-sample/registry/ARB/matrix_palette.txt)

Edit: It's not widely supported though (I don't know any vendor who supports it right now)

[This message has been edited by Humus (edited 04-09-2002).]

Lucretia
04-10-2002, 12:20 AM
As for ARB_vertex_blend, I'm already using this, but I'm only using the two MODELVIEW matrices - I cannot remember if there are more or if I just implemented 2 ;-)

Now, what hardware drivers implement the ARB_matrix_palette extension?

Thanks,
Luke.

Humus
04-10-2002, 02:09 AM
Originally posted by Lucretia:
As for ARB_vertex_blend, I'm already using this, but I'm only using the two MODELVIEW matrices - I cannot remember if there are more or if I just implemented 2 ;-)

Now, what hardware drivers implement the ARB_matrix_palette extension?

Thanks,
Luke.

You can query how many matrixes are available. The original Radeon had 4 I remember, not sure about Radeon 8500.
I don't think any hardware drivers supports the matrix palette extension right now, perhaps we will see it in the future.