How can I convert curveTo() to a list of Points?

Question

Take the following AS3 that will draw a curved line using curveTo():

var line:Shape = new Shape();

line.x = line.y = 20;
line.graphics.lineStyl         


        

Answer 1

curveTo() is used to draw a quadratic bezier curve, where a bezier curve is calculated between two endpoints and in relation to two anchor points, and a quadratic bezier curve is one where both anchor points have the same coordinates.

Bezier curves are calculated by a number of equations that allow you to find x and y coordinates for a point that is reached at a given time along the path, so this already fits your needs quite well. You can find general information about bezier curves on this page.

All you need to do to get the coordinate points is translate these equations to ActionScript. And luckily, Paul Tondeur has a nice blog post showing how to do this. His solution is used to draw cubic bezier curves, but you can easily change the code to return coordinates for what you're trying to do.