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Thread: How to multiply point by Current Matrix?

  1. #1
    Member Contributor
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    How to multiply point by Current Matrix?

    I just want to multiply my vertex point by the current matrix. Is there an openGL routine to do this? Do I need to put my point into a 4X4 matrix first and then multiply?
    P4 2Ghz, GEFORCE4, 512 Meg RAM, WIN2000, VStudio 6.0

  2. #2
    Member Contributor
    Join Date
    Apr 2002
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    Re: How to multiply point by Current Matrix?

    I've been doing a little research and it sounds like doing a "glGetFloatV" on the current matrix is very slow. Is the best way then, to keep an internal copy of my matrix and do calculations with it and load it into the current matrix when needed?

    Thanks!
    P4 2Ghz, GEFORCE4, 512 Meg RAM, WIN2000, VStudio 6.0

  3. #3
    Senior Member OpenGL Guru
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    Re: How to multiply point by Current Matrix?

    If you must do it every frame, I suggest you keep and internal copy of the matrix, and never use any glGet* whatsoever. If you need to do it a few time now and then, a glGet won't hurt that much.

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