Trying to Draw a 2D Triangle in OpenGL ES 2.0

Posted by Nathan Campos on Game Development See other posts from Game Development or by Nathan Campos
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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