Trying to Draw a 2D Triangle in OpenGL ES 2.0
        Posted  
        
            by 
                Nathan Campos
            
        on Game Development
        
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        Published on 2012-08-05T02:41:10Z
        Indexed on 
            2012/09/04
            15:55 UTC
        
        
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I'm trying to convert a code from OpenGL to OpenGL ES 2.0 (for the BlackBerry PlayBook). So far what I got is this (just the part of the code that should draw the triangle):
void setupScene() {
    glClearColor(250, 250, 250, 1);
    glViewport(0, 0, 600, 1024);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
}
void drawScene() {
    setupScene();
    glColorMask(0, 0, 0, 1);
    const GLfloat triangleVertices[] = {
        100,   100,
        150,  0,
        200,   100
    };
    glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, triangleVertices);
    glEnableVertexAttribArray(0);
    glDrawArrays(GL_TRIANGLES, 0, 2);
}
void render() {
    drawScene();
    bbutil_swap();
}
The problem is that when I launch the app instead of showing me the triangle the screen just flickers (very fast) from white to gray. Any idea what I'm doing wrong?
Also, here is the entire code if you need: Full source code
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