Main.cpp

    GL::VertexElement positionElem(GL::Semantic::Position, 3);
    float positionData[] = {
        200, 30, 0,
        500, 30, 0,
        350, 100, 0
    };

    positionElem.getStream().write(positionData);
    buffer.addElement(positionElem);
    buffer.reloadBuffer();