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copied!<p>Edit 2: Okay, I see the problem you're running into -- it's a limitation I'd forgotten about (so the code I'd posted previously was dead wrong and wouldn't work at all). The problem is that you're not allowed to call <code>glRotate</code> between a <code>glBegin</code>/<code>glEnd</code> pair -- if you do, it'll set an error flag, and no more drawing will be done.</p> <p>That does mean you pretty much have to handle the rotation yourself. Fortunately, that's a bit simpler than you've tried to make it:</p> <pre><code>static const double pi = 3.1416; for (int point=0; point<NUM_POINTS; point++) { glBegin(GL_LINE_STRIP); for (double theta = 0.0; theta < 2.0 * pi; theta += pi/6.0) { double x = cos(theta); double z = sin(theta); glVertex3d(points[point][0]*x, points[point][1], -1.0-points[point][0]*z); } glEnd(); } </code></pre> <p>As-is, this code uses -1.0 along the Z axis as the center of rotation. You can obviously move that where you wish, though anything outside your clipping frustum obviously won't display.</p> <p>Also note that to get a wireframe, you'll have to draw both your "vertical", and your "horizontal" lines separately, so the code will look something like this:</p> <pre><code>for (int point=0; point<NUM_POINTS; point++) { glBegin(GL_LINE_STRIP); for (double theta = 0.0; theta < 2.0 * pi; theta += pi/6.0) { double x = cos(theta); double z = sin(theta); glVertex3d(points[point][0]*x, points[point][1], -1.0 - points[point][0]*z); } glEnd(); } for (double theta = 0.0; theta < 2.0 * pi; theta += pi/6.0) { glBegin(GL_LINE_STRIP); for (int point=0; point<NUM_POINTS; point++) { double x = cos(theta); double z = sin(theta); glVertex3d(points[point][0]*x, points[point][1], -1.0 - points[point][0]*z); } glEnd(); } </code></pre>

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