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Another glDrawElements thread

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Ok, I'm trying to use glDrawElements to replace the calls in between the /* */ comment tags. However, my replacement code don't work; I end up with a blank screen, were there should be a multicoloured square. I'm using SDL to control the windows, etc.
static const Uint8      Indice[] = { 0, 1, 2, 3};
    static const GLfloat    Vertice[] = { -0.5f, -0.5f, -0.5f, 0.5f, -0.5f, -0.5f, 
                                             -0.5f, 0.5f, -0.5f, 0.5f, 0.5f, -0.5f };
    static const GLfloat    Colours[] = {1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 
                                            1.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f };


    glMatrixMode( GL_MODELVIEW );


    glColor3f(Colours[0], Colours[1], Colours[2]);
    glVertex3f(Vertice[0], Vertice[1], Vertice[2]);

    glColor3f(Colours[3], Colours[4], Colours[5]);
    glVertex3f(Vertice[3], Vertice[4], Vertice[5]);

    glColor3f(Colours[6], Colours[7], Colours[8]);
    glVertex3f(Vertice[6], Vertice[7], Vertice[8]);

    glColor3f(Colours[9], Colours[10], Colours[11]);
    glVertex3f(Vertice[9], Vertice[10], Vertice[11]);


    glIndexPointer(GL_FLOAT, 0, Colours);
    glVertexPointer(3, GL_FLOAT, 0, Vertice);
    glDrawElements(GL_TRIANGLE_STRIP, 2, GL_UNSIGNED_BYTE, Indice);



Btw, I checked the code between the tags and it works

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The second parameter is the number of indices you want to draw (usually, the number of indices in the index array). You're only drawing 2 vertices, but a triangle needs atleast 3 to form a complete triangle. 4 is the correct value in this case.

And why are you using the index color array for the RGB color array? You should probably use glColorPointer instead.

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Ahh, much better now. It now works correctly. The reason why I used glIndexPointer was because of the msdn library statement:

The glIndexPointer function defines an array of color indexes.

Which confused me. Anyway, thanks for your help

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