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copied!<p>I use this function to draw circle segments (I think I ported it from an online AS2 example on how to draw full circles long ago):</p> <pre><code> /** * Draw a segment of a circle * @param graphics the graphics object to draw into * @param center the center of the circle * @param start start angle (radians) * @param end end angle (radians) * @param r radius of the circle * @param h_ratio horizontal scaling factor * @param v_ratio vertical scaling factor * @param new_drawing if true, uses a moveTo call to start drawing at the start point of the circle; else continues drawing using only lineTo and curveTo * */ public static function drawCircleSegment(graphics:Graphics, center:Point, start:Number, end:Number, r:Number, h_ratio:Number=1, v_ratio:Number=1, new_drawing:Boolean=true):void { var x:Number = center.x; var y:Number = center.y; // first point of the circle segment if(new_drawing) { graphics.moveTo(x+Math.cos(start)*r*h_ratio, y+Math.sin(start)*r*v_ratio); } // draw the circle in segments var segments:uint = 8; var theta:Number = (end-start)/segments; var angle:Number = start; // start drawing at angle ... var ctrlRadius:Number = r/Math.cos(theta/2); // this gets the radius of the control point for (var i:int = 0; i<segments; i++) { // increment the angle angle += theta; var angleMid:Number = angle-(theta/2); // calculate our control point var cx:Number = x+Math.cos(angleMid)*(ctrlRadius*h_ratio); var cy:Number = y+Math.sin(angleMid)*(ctrlRadius*v_ratio); // calculate our end point var px:Number = x+Math.cos(angle)*r*h_ratio; var py:Number = y+Math.sin(angle)*r*v_ratio; // draw the circle segment graphics.curveTo(cx, cy, px, py); } } </code></pre> <p>I think it's close enough to perfect circles. I don't really understand the math inside, but I hope the parameters are clear enough for you.</p>

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