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supagu
11-05-2004, 03:22 PM
okay, im just starting out with skinning, and found this extensions that should provide useful.

What i have set up is 2 bones in a rectangle shape box.

i have gone and set the first 4 matrices to be indentity (also tried setting to camera look at matrix)

GL_MODELVIEW0_ARB -> GL_MODELVIEW3_ARB

i have set up my weights, but how do i specify what matrix which weight refers too?

say i have a vertex with 4 weights:
0.5, 0.5, 0.0, 0.0

and bone indexes:
1, 0, 0, 0

so i should get an even blend between bone 0 and 1,
but all vertex blend extension supplies is a weight?

any way, so i set my weights, and identity matrices as i just wanna see my box on screen in its default pos, but i get screwed up polys random when i move the camera?

jwatte
11-07-2004, 09:14 AM
The vertex weighting extension is useless (http://www.mindcontrol.org/~hplus/graphics/vert_weighting.html) .

Korval
11-07-2004, 12:14 PM
But this is about the ARB_vertex_blend extension. Which is somewhat less useless than the vertex blend extension, but not by too much.

jwatte
11-07-2004, 08:05 PM
It's still useless.

I should add, for clarity, that the link I posted also contains a sketch for how you actually want to do it (using software skinning).

If you want to push it on hardware, look into the matrix palette skinning examples in the NVIDIA OpenGL SDK.

supagu
11-07-2004, 11:35 PM
right im downloading this:
http://developer.nvidia.com/object/sdk_home.html

hope thats what you meant,

as for skinning i got the demo from here:
http://www.ati.com/developer/sdk/RADEONSDK/Html/Samples/OpenGL/VertexBlend.html

which seems to render a whole skinned model in a single draw call?

supagu
11-08-2004, 11:17 PM
the only OGL skinning sample in thier SDK uses shaders :-/

Korval
11-09-2004, 07:57 AM
the only OGL skinning sample in thier SDK uses shadersYeah, that's the general idea.

supagu
11-09-2004, 11:08 PM
hrmm knowing my luck its not gonna work with shaders, so i'd really like to get it working with out, the ATI demo still has me stumped as it looks like they draw thier whole model in 1 draw call :-/

CrazyButcher
11-10-2004, 12:47 AM
ARB_vertex_program is really quite spread, you should give it a try

Humus
11-10-2004, 01:35 PM
Unless you need to support R100 hardware, I too would suggest using shaders.