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Multitexturing

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Started by dandrestor January 28, 2011 08:03 PM

3 comments, last by dandrestor 13 years, 2 months ago

dandrestor

102

Author

January 28, 2011 08:03 PM

Hi guys,

I'm trying to use multitexturing in my program but I'm hopelessly lost... Help!!!

I have written a basic fragment shader which declares two uniform sampler2D variables.



uniform sampler2D tex1;

uniform sampler2D tex2;

...

t1 = texture2D(tex1, texCoord1);

t2 = texture2D(tex2, texCoord2);

My opengl display function does something like:



glActiveTexture(GL_TEXTURE1);

glBindTexture(GL_TEXTURE_2D, tex1);

glEnable(GL_TEXTURE_2D);

glActiveTexture(GL_TEXTURE0);

glBindTexture(GL_TEXTURE_2D, tex0);

glEnable(GL_TEXTURE_2D)

...

glClientActiveTexture(GL_TEXTURE0);

glEnableClientState(GL_TEXTURE_COORD_ARRAY);

glTexCoordPointer(2, GL_FLOAT, 32, buffer0);

glClientActiveTexture(GL_TEXTURE1);

glEnableClientState(GL_TEXTURE_COORD_ARRAY);

glTexCoordPointer(2, GL_FLOAT, 32, buffer1);

No matter what I do, it seems that in my shader the two uniforms point to the same texture object! I think the call to glBindTexture is wrong... Could you help me understand this?

Thanks a bunch!
D.

kilah

514

January 28, 2011 08:09 PM

You need to upload the multitexture information into the shader. Right now your shader is streaming only the first texture, as you are not linking the shader with any other texture even if you are binding texture from your OGL code (short answer: glUniform to upload texture to bind).