Here's the general purpose arc drawing routine. It accepts two additional arguments, bA (begin angle) and eA (end angle), both of which are expressed in degrees (0-360).

code:


degToRad = Math.PI/180;



MovieClip.prototype.drawArc = function(x,y,radius, bA,eA)

{

	if (eA < bA) eA += 360;

	var r = radius;



	var n= Math.ceil((eA-bA)/45);

	

	var theta = ((eA-bA)/n)*degToRad;

	var cr = radius/Math.cos(theta/2);

	var angle = bA*degToRad;

	var cangle = angle-theta/2;

	

	this.moveTo(x+r*Math.cos(angle), y+r*Math.sin(angle));

	for (var i=0;i < n;i++) 

	{

		angle += theta;

		cangle += theta;

		var endX = r*Math.cos (angle);

		var endY = r*Math.sin (angle);

		var cX = cr*Math.cos (cangle);

		var cY = cr*Math.sin (cangle);

		this.curveTo(x+cX,y+cY, x+endX,y+endY);

	}

}


This is a modified version of the routine I used to make this:

http://krazydad.com/bestiary/bestiary_piechart.html