Part of the Khronos Group
OpenGL.org

The Industry's Foundation for High Performance Graphics

from games to virtual reality, mobile phones to supercomputers

Results 1 to 10 of 10

Thread: GL_ARB_vertex_blend

  1. #1
    Junior Member Regular Contributor
    Join Date
    Feb 2004
    Location
    Aus
    Posts
    148

    GL_ARB_vertex_blend

    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?

  2. #2
    Senior Member OpenGL Guru
    Join Date
    Mar 2001
    Posts
    2,704

    Re: GL_ARB_vertex_blend

    "If you can't afford to do something right,
    you'd better make sure you can afford to do it wrong!"

  3. #3
    Senior Member OpenGL Guru
    Join Date
    Mar 2001
    Posts
    3,768

    Re: GL_ARB_vertex_blend

    But this is about the ARB_vertex_blend extension. Which is somewhat less useless than the vertex blend extension, but not by too much.

  4. #4
    Senior Member OpenGL Guru
    Join Date
    Mar 2001
    Posts
    2,704

    Re: GL_ARB_vertex_blend

    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.
    "If you can't afford to do something right,
    you'd better make sure you can afford to do it wrong!"

  5. #5
    Junior Member Regular Contributor
    Join Date
    Feb 2004
    Location
    Aus
    Posts
    148

    Re: GL_ARB_vertex_blend

    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/RAD...rtexBlend.html

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

  6. #6
    Junior Member Regular Contributor
    Join Date
    Feb 2004
    Location
    Aus
    Posts
    148

    Re: GL_ARB_vertex_blend

    the only OGL skinning sample in thier SDK uses shaders :-/

  7. #7
    Senior Member OpenGL Guru
    Join Date
    Mar 2001
    Posts
    3,768

    Re: GL_ARB_vertex_blend

    the only OGL skinning sample in thier SDK uses shaders
    Yeah, that's the general idea.

  8. #8
    Junior Member Regular Contributor
    Join Date
    Feb 2004
    Location
    Aus
    Posts
    148

    Re: GL_ARB_vertex_blend

    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 :-/

  9. #9
    Member Regular Contributor CrazyButcher's Avatar
    Join Date
    Jan 2004
    Location
    Germany
    Posts
    402

    Re: GL_ARB_vertex_blend

    ARB_vertex_program is really quite spread, you should give it a try

  10. #10
    Senior Member OpenGL Guru Humus's Avatar
    Join Date
    Mar 2000
    Location
    Stockholm, Sweden
    Posts
    2,444

    Re: GL_ARB_vertex_blend

    Unless you need to support R100 hardware, I too would suggest using shaders.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •