As each fillet is drawn, the end point for the fillet becomes the start point for the next fillet. Upon completion, the current (X,Y) position is the end point of the last fillet. Each fillet is controlled by a set of coordinates for two connected lines and by a sharpness value. The fillet is tangential to the start point of the first line and to the end point of the second line.

The sharpness value is determined from:

Sharpness = WD/DB
where:
       W is the mid-point of the line joining the end points
       B is the control point above the top of the fillet
       D is the point where the fillet intersects the line WC

Refer to the function "GpiPolyFillet" in the Presentation Manager Programming Reference for more information.