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copied!<p>So. <code>glGenTextures</code> takes two parameters. An <code>int</code>, and a <code>GLuint*</code>. The <code>int</code> tells GL how many textures to generate, and the <code>GLuint*</code> is an array of <code>GLuint</code>s (where to generate the textures). The reason you do the following...</p> <pre><code>GLuint m_TextureID glGenTextures(1, &m_TextureID) </code></pre> <p>is because you only have one texture. If you have more than one, you would do this:</p> <pre><code>// Substitute 'n' for some const number GLuint *textures = new GLuint[n]; glGenTextures(n, textures); </code></pre> <p>This way, you are telling GL I want to generate n textures, and here's an array with allocated space for at least that many textures.</p> <p>Say you want to use both of them in your draw loop, you would implement that like this:</p> <pre><code>void draw() { glBindTexture(GL_TEXTURE_2D, textures[0]); // Tell GL to use the first texture // Any drawing here will use first texture glBindTexture(GL_TEXTURE_2D, textures[1]); // Tell GL to use the second textures // Any drawing here will use second texture glBindTexture(GL_TEXTURE_2D, 0); // Set the GL texture to NULL, standard cleanup } </code></pre> <p>Make sure to <code>delete textures;</code> at the end of your program to properly clean up after allocating that space.</p> <p>There are also ways to not have to bind separate textures. You can use what's called a "texture atlas". Basically, this is one bitmap that contains multiple sub-images. So you just generate and bind one bitmap, and use separate parts of it.</p> <p>To deal with multiple bitmaps, do this:</p> <pre><code>Bitmap image[2]; image[0].loadBMP("myTexture.bmp"); image[1].loadBMP("myOtherTexture.bmp"); </code></pre> <p>Then follow the process to generate one bitmap for both bitmaps.</p> <hr> <h2>Everything below this line is responding to your updated question.</h2> <p>This should pretty much do what you're trying to do.</p> <pre><code>// Global variable GLuint textures[2]; // init function void init() { textures = new GLuint[2]; glGenTextures(2, textures); loadTexture(textures[0], "texture1.bmp"); loadTexture(textures[1], "texture2.bmp"); } void loadTexture(GLuint texture, const char* filename) { Bitmap image; image.loadBMP(filename); glBindTexture(GL_TEXTURE_2D, texture); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE , GL_MODULATE); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); gluBuild2DMipmaps(GL_TEXTURE_2D, 3, image.width, image.height, GL_RGB, GL_UNSIGNED_BYTE, image.data); } // draw function void draw() { glBegin(GL_QUADS); //TOP glBindTexture(GL_TEXTURE_2D, textures[0]); glNormal3f(0,1,0); glColor4f(1,1,1,0); glTexCoord2f(0.0f,0.0f); glVertex3f(-4.5, 0.3, 2); //bottom left glTexCoord2f(1.0f,0.0f); glVertex3f(-4.5, 0.3, 2.5); //bottom right glTexCoord2f(1.0f,1.0f); glVertex3f(4.5, 0.3, 2.5); //top right glTexCoord2f(0.0f,1.0f); glVertex3f(4.5, 0.3, 2); //top left glEnd(); } // cleanup function void cleanup() { delete textures; } </code></pre> <p>Some of the issues you are pointing out aren't exactly OpenGL related, they are more C/C++ related. I know this isn't the answer you're looking for, but it would probably help you out a lot to learn about C functions, pointers, arrays, etc, and spend a solid month working closely with functions/pointers/arrays before moving on to something like OpenGL, which requires a pretty moderate understanding of C.</p>

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