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 3 of 3

Thread: Texture bug?

  1. #1

    Texture bug?

    Following is my fragment program for hatching effect rendering:

    varying vec3 HatchWeights0;
    varying vec3 HatchWeights1;

    uniform sampler2D Hatch0;
    uniform sampler2D Hatch1;
    uniform sampler2D Hatch2;
    uniform sampler2D Hatch3;
    uniform sampler2D Hatch4;
    uniform sampler2D Hatch5;

    void main (void)
    {
    vec4 hatchTex0 = texture2D(Hatch0, vec2(gl_TexCoord[0])) * HatchWeights0.x;
    vec4 hatchTex1 = texture2D(Hatch1, vec2(gl_TexCoord[0])) * HatchWeights0.y;
    vec4 hatchTex2 = texture2D(Hatch2, vec2(gl_TexCoord[0])) * HatchWeights0.z;
    vec4 hatchTex3 = texture2D(Hatch3, vec2(gl_TexCoord[0])) * HatchWeights1.x;
    vec4 hatchTex4 = texture2D(Hatch4, vec2(gl_TexCoord[0])) * HatchWeights1.y;
    vec4 hatchTex5 = texture2D(Hatch5, vec2(gl_TexCoord[0])) * HatchWeights1.z;

    vec4 hatchColor1 = hatchTex0+hatchTex2+hatchTex4;
    vec4 hatchColor2 = hatchTex1+hatchTex3+hatchTex5;

    gl_FragColor = hatchColor1;
    }

    It is work, but what I want is

    gl_FragColor = hatchColor1+hatchColor2;

    This will have error when call glUseProgramObjectARB(0);

    It will be ok, if in this way,
    gl_FragColor = hatchColor1;
    or
    gl_FragColor = hatchColor2;
    or
    gl_FragColor = sum of any three color item.

    I have tried use clamp(?, 0.0, 1.0), or
    gl_FragColor = hatchColor1*0.5+hatchColor2*0.5, but all can't pass it?

    Could anyone give me some hints?

    By the way, I am using ATI 9800XT and lastest driver.

  2. #2
    Junior Member Regular Contributor
    Join Date
    May 2003
    Location
    Germany
    Posts
    229

    Re: Texture bug?

    Take a look at this thread : http://www.opengl.org/discussion_boa...ML/000014.html

    It seems that ATI's glSlang-Implementation has problems with texture-reads and moreover mistakes some normale reads as dependant reads. This has (if I'm not mistaken) also been a problem in ARB_FP, but seems to have been fixed there.
    Hope that this also gets fixed in a comming driver release, since it's sad that you can't do more than 5 texturereads even with some tricks and workarounds.

  3. #3

    Re: Texture bug?

    Thanks for the information.

    It seems I have to wait for ATI guys fix the bug.


    [This message has been edited by tang_m (edited 02-10-2004).]

Posting Permissions

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