Hkon

int LoadBitmap(std::string filename)
{
    unsigned char *l_texture; // The pointer to the memory zone in which we will load the texture
    int width, height, size; //Storage for bitmap-info
    num_texture++; // A variable which keeps track of the number of textures

    FILE *mf;
    mf = fopen(filename.c_str(), "rb"); //Open file
    if (mf == NULL)                        //Check if the file opened
        exit(13);

    fseek(mf, 18, SEEK_SET);
    fread(&width, sizeof(int), 1, mf);    //Read in the width of the image

    fseek(mf, 22, SEEK_SET);
    fread(&height, sizeof(int), 1, mf);    //Read in the height of the image

    size = height * width * 4;        //The size for all the important bytes

    // Now we need to allocate the memory for our image (width * height * color deep)
    l_texture = (unsigned char *) malloc(size);
    // And fill it with zeros
    memset(l_texture, 0, size);

    // At this point we can read every pixel of the image
    for (int i=0; i < size; i += 4)
    {
            // We load the red, green and blue values
            char r, g, b;
            fread(&r, 1, 1, mf);
            fread(&g, 1, 1, mf);
            fread(&b, 1, 1, mf);

            // And store it
            l_texture[i+0] = r; // Red component
            l_texture[i+1] = g; // Green component
            l_texture[i+2] = b; // Blue component
            l_texture[i+3] = 255; // Alpha value
    }

    fclose(mf); // Closes the file stream

    glBindTexture(GL_TEXTURE_2D, num_texture); // Bind the ID texture specified by the 2nd parameter

    // The next commands sets the texture parameters
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); // If the u,v coordinates overflow the range 0,1 the image is repeated
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // The magnification function ("linear" produces better results)
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST); //The minifying function

    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE); // We don't combine the color with the original surface color, use only the texture map.

    // Finally we define the 2d texture
    glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, l_texture);

    // And create 2d mipmaps for the minifying function
    gluBuild2DMipmaps(GL_TEXTURE_2D, 4, width, height, GL_RGBA, GL_UNSIGNED_BYTE, l_texture);

    free(l_texture); // Free the memory we used to load the texture

    return num_texture; // Returns the current texture OpenGL ID
}