Hello, I'm trying to use Multitexturing with GLSL. The following lines should be getting the location of my uniform sampler2D texture units from the shader and binding them to texture unit 0 and texture unit 1. int loc = m_pExt->glGetUniformLocationARB(hShaderPrograms[x].hProgamObject,"textureUnit"); m_pExt->glUniform1iARB(loc,0); int loc2 = m_pExt->glGetUniformLocationARB(hShaderPrograms[x].hProgamObject,"textureUnit2"); m_pExt->glUniform1iARB(loc2,1); The problem is that inside the shader both textureUnit and textureUnit2 both reference the same texture(TU0). I'm setting the textures with.. glActiveTextureARB(GL_TEXTURE0_ARB); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, tex1ID); glActiveTextureARB(GL_TEXTURE1_ARB); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, tex2ID); If I use multitexturing without the shader I can use both textures but when using the shader I can't seem to get any textures besides TU0.. anyone know anything about this?

shader code?

Fragment shader is like this to test if the 2nd texture works.

varying vec2 texCoord;
uniform sampler2D textureUnit;
uniform sampler2D textureUnit2;

void main()
{
vec4 tempFrag = texture2D(textureUnit,texCoord);
vec4 tempFrag2 = texture2D(textureUnit2,texCoord);
gl_FragColor = tempFrag2;
}


Setting FragColor to tempFrag or tempFrag2 makes no difference, it displays the same texture in both cases.

Quote:Original post by AndyPandyV2
glActiveTextureARB(GL_TEXTURE0_ARB);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, tex1ID);

glActiveTextureARB(GL_TEXTURE1_ARB);
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, tex2ID);

You need this line also when setting up your multitexturing and I am assuming your using Vertex arrays for texture coordinates?


HTH

It seems like this code can be removed completely and it makes no difference.. I don't believe the the TU are being bound properly for whatever reason. All sampler2D's just seem to be defaulting to TU0.

int loc2 = m_pExt->glGetUniformLocationARB(hShaderPrograms[x].hProgamObject,"textureUnit2");
m_pExt->glUniform1iARB(loc2,1)

Thanks for the help, I tried glGetError() and on binding to any TU besides TU0 it generates error 1281 "invalid value".

glUniform1iARB(loc2,1);

I assume you've checked the value being returned in loc2?

Tried putting it in a loop and checking every Uniform from 0-255, it said Invalid operation for every one except the location of loc/loc2 which it says Invalid value if I try and bind anything other then TU0.