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Thread: are vertex arrays non-destructive?

  1. #1
    Member Regular Contributor
    Join Date
    Feb 2000
    Location
    milano, italy
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    are vertex arrays non-destructive?

    i'm developing a realtime landscape renderer wich takes elevation data from a fractal, and since the fractal is quite complex (multifractal perlin noise) and it takes some time to sample, i've found a way to reduce sampling down to a minimum, by sampling only when is really needed.

    the method i've implemented relys on a 2-dimensional wrappable buffer, and the data into the buffer MUST remain coherent all the time: my code stores values correctly, but sometime the polygons appear not as i expect.

    since there are many shared vertex, every with position, color, normal, texture and fog coordinates, i use vertex arrays to let opengl do the calculation once.

    to specify vertex arrays data i use gl___Pointer() family functions, and i dereference the arrays with glArrayElement().

    now, does opengl leave unchanged the data into my arrays, after i have dereferenced?

    i hope the answer will be yes...
    ...and i hope i was clear enough.

    Dolo/\/\ightY

    PS: just a note about how clever design can do for applications : before the renderer was running @25 fps, now it runs @130 !!
    Dolo/\/\ightY

  2. #2
    Member Regular Contributor
    Join Date
    Feb 2000
    Location
    milano, italy
    Posts
    282

    Re: are vertex arrays non-destructive?

    ok. i've fixed the bug, and as usual it was mine... but answer the same !

    Dolo/\/\ightY
    Dolo/\/\ightY

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