Thread: Why aren't my textures being shown? (OpenGL)

I have looked over this program and compared it to other ones that had textures working but can't seem to find the problem. It basically draws different sized quads from triangles and they all have a raindrop texture applied to them, but it doesn't work. Did I miss something here. Here is the setup and rendering parts of my code.

Code:

void ParticleScene::setupView(int width, int height)
{
    glViewport(0, 0, width,height);

    float ratio = static_cast<float>(width)/static_cast<float>(height);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(42, ratio, 0, 100);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}


void ParticleScene::initialize()
{
    glDisable(GL_DEPTH_TEST);
    glDepthFunc(GL_LEQUAL);
    glClearColor(0.0, 0.0, 0.0, 0.0);

    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE);

    //load the raindrop textures
    glEnable(GL_TEXTURE_2D);
    glGenTextures(1, &rainTexture);

    image.Load("Data/star.tga");
    glBindTexture(GL_TEXTURE_2D, rainTexture);
    gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGBA, image.GetWidth(), image.GetHeight(),
                            GL_RGBA, GL_UNSIGNED_BYTE, image.GetImage());
    image.Release();
/////

Code:

void ParticleScene::render()
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    gluLookAt(0, 0, 80,
              0, 0, -1,
              0, 1, 0);

    //just lines to indicate bundary of rainfall
    glBegin(GL_LINES);
        glColor3f(1.0, 0.0, 0.0);
        glVertex3f(-40, STARTING_HEIGHT, 0);
        glVertex3f(40, STARTING_HEIGHT, 0);

        glColor3f(0.0, 1.0, 0.0);
        glVertex3f(-40, ENDING_HEIGHT, 0);
        glVertex3f(40, ENDING_HEIGHT, 0);
    glEnd();

    
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
    for(size_t i = 0; i < MAX_PARTICLES; ++i)
    {
        if(raindrops[i].alive == true)
        {
            float sz = raindrops[i].size;
            float x = raindrops[i].xPos;
            float y = raindrops[i].yPos;
            float z = raindrops[i].zPos;

            glBindTexture(GL_TEXTURE_2D, rainTexture);
            glBegin(GL_TRIANGLE_STRIP);
                glColor4f(0.0, 0.0, raindrops[i].blue, raindrops[i].alpha);
                glTexCoord2i(1, 1); glVertex3f(x + sz, y + sz, z);
                glTexCoord2i(0, 1); glVertex3f(x - sz, y + sz, z);
                glTexCoord2i(1, 0); glVertex3f(x + sz, y - sz, z);
                glTexCoord2i(0, 0); glVertex3f(x - sz, y - sz, z);
            glEnd();

the "raindrops" show as blocks with the attributes in their structures but neither the alpha or the textures seem to be enabled

I'd guess it's one of two things:

You're doing something wrong when creating the texture. This would be in your image.Load() call, which I can't see.

Or, you need to glEnable(GL_TEXTURE_2D); before you draw the texture mapped objects.

I might not have expressed that clearly enough, I meant to enable texturing here:

Code:

    glEnable(GL_TEXTURE_2D); //<--RIGHT HERE
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
    for(size_t i = 0; i < MAX_PARTICLES; ++i)
    {
        if(raindrops[i].alive == true)
        {
            float sz = raindrops[i].size;
            float x = raindrops[i].xPos;
            float y = raindrops[i].yPos;
            float z = raindrops[i].zPos;

            glBindTexture(GL_TEXTURE_2D, rainTexture);
            glBegin(GL_TRIANGLE_STRIP);
                glColor4f(0.0, 0.0, raindrops[i].blue, raindrops[i].alpha);
                glTexCoord2i(1, 1); glVertex3f(x + sz, y + sz, z);
                glTexCoord2i(0, 1); glVertex3f(x - sz, y + sz, z);
                glTexCoord2i(1, 0); glVertex3f(x + sz, y - sz, z);
                glTexCoord2i(0, 0); glVertex3f(x - sz, y - sz, z);
            glEnd();

You may also want to move the glBindTexture() call outside of the loop, since all your particles use the same texture. Minor efficiency thing.

You may also want to try it as a quad first, just to see if your triangle coords might be messed up.

OK, here's one that catches a lot of people.

The dimensions of OpenGL textures must be powers of 2.

What are the dimensions of your texture?