# OpenGL Specifying multiple textures causes only the last one to be usable [A-HA! I suck!]

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bool LoadTexture(const char * file_name, GLuint & texture)
{

if (tex == NULL)
return false;

glGenTextures(1, &texture);

glBindTexture(GL_TEXTURE_2D, texture);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, tex->w, tex->h, 0, GL_RGB, GL_UNSIGNED_BYTE,
tex->pixels);

SDL_FreeSurface(tex);

return true;
}


You can pretty much ignore the SDL-specific code. I'm pretty confident that the problem is somewhere in my OpenGL code. Thanks a bunch! [Edited by - silverphyre673 on June 5, 2007 12:11:05 PM]

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That is a strange problem indeed.
Just a shot in the dark, but have you tried explicitly setting glActiveTexture(GL_TEXTURE0); before using glBindTexture ? Maybe the texture units are changed somewhere.

I really dont know, the code you provided should work just fine...

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Are you using different values for &texture?

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Yep. What I've been doing is calling the LoadTexture function with different offsets of an std::vector<GLuint>, like this:

std::vector<GLuint> TEXTURES;void LoadTextures(){    LoadTexture("dirt.png", TEXTURES[0]);    LoadTexture("grass.png", TEXTURES[1]);    LoadTexture("pavement.png", TEXTURES[2]);    LoadTexture("water.png", TEXTURES[3]);}

After the LoadTextures() function is called, TEXTURES stores the values {1, 2, 3, 4}, as should be expected.

I think I'm just going to forget about using straight OpenGL and go with OGRE instead. Maybe that'll clear up some of these issues...

[EDIT]

Screw it. I just rewrote the image loading code. It looks almost exactly the same to me -- and doesn't look like I changed anything that would have made a different. However, it seems to work now, which makes me a confused panda.

[EDIT #2]

Nevermind. It worked on my test rendering code (just rendering a single quad); I was able to cycle through each texture normally. Unfortunately, when I try to render the map I was originally having issues drawing, I get the same error. I think the problem must be in my drawing code:

//I checked, and the value of top_texture is as it should be for error-free//code.glBindTexture(GL_TEXTURE_2D, top_texture);glTexCoord2f(0.0, 0.0); glVertex3f(x, y, z);glTexCoord2f(1.0, 0.0); glVertex3f(x + cell_size, y, z);glTexCoord2f(1.0, 1.0); glVertex3f(x + cell_size, y + cell_size, z);glTexCoord2f(0.0, 1.0); glVertex3f(x, y + cell_size, z);

[Edited by - silverphyre673 on June 5, 2007 12:42:08 PM]

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