> Some 2D graphics systems do not allow you to draw arcs. Instead they

> want you to approximate the arcs using Bezier curves. An example is

> Adobe's Portable Document Format (PDF).

> Does anyone know the formula for doing this? I need to draw arbitrary

> arcs (not just full circles).

> For arcs up to 90 degrees, from memory, I think you pick cubic

bezier endpoints p0, p3 to be the arc endpoints, and internal

points p1, p2 to satisfy:

* vectors p1-p0 and p2-p3 tangential at the arc endpoints

* |p1-p0| = |p2-p3|

* midpoint of the Bezier equals midpoint of the arc

How about you do the maths and post back a reply?

For arc > 90 degrees, break it up into smaller arcs each no wider

than 90 degrees, and generate a bezier cubic for each one.

Hope this helps.

George Politis.