}
public void invokeStep (InputEvent inputEvent, int x, int y, int anchorX, int anchorY, DrawingView view) {
int dx = x-anchorX;
int dy = y-anchorY;
RoundRectangleFigure owner = (RoundRectangleFigure)owner();
Rectangle r = owner.getDisplayBox();
Point originalRadius = ((UndoActivity)getUndoActivity()).getOldRadius();
int rx = Geom.range(0, r.width, 2*(originalRadius.x/2 + dx));
int ry = Geom.range(0, r.height, 2*(originalRadius.y/2 + dy));
owner.setArc(rx, ry);
}