1.GL_QUADS, GL_TRIANGLES, GL_LINES, GL_LINE_STRIP, GL_QUAD_STRIP, GL_LINE_LOOP, GL_TRIANGLE_STRIP, GL_POINTS, GL_POLYGON
2.GL_QUAD, GL_TRIANGLE, GL_LINE, GL_LINE_STRIP, GL_QUAD_STRIP, GL_LINE_LOOP, GL_TRIANGLE_STRIP, GL_POINT, GL_POLYGON
3.TRUE or FALSE
4.GL_START, GL_END