ArcStroker

From Fmepedia

ArcStroker is a Workbench Transformer. Replaces a circular arc with a number of straight lines by interpolating points along the arc and connecting them. The more points are interpolated, the more accurate the representation of the original arc will be. The number of interpolated points may either be entered as a number, or can be taken from the value of a feature attribute by selecting the attribute name from the pull-down list. If you enter n, FME will create an arc with n+1 points.

If the number of points is zero, then a reasonable number of points will be interpolated for the arc.

Ellipses will be output as polygons, arcs will be output as polylines.