+void
+PolyLine::set_steps (Points const & points, bool stepped)
+{
+ if (!stepped) {
+ PolyItem::set(points);
+ return;
+ }
+
+ Points copy;
+ for (Points::const_iterator p = points.begin(); p != points.end();) {
+ Points::const_iterator next = p;
+ ++next;
+
+ copy.push_back(*p);
+ if (next != points.end() && next->x != p->x) {
+ copy.push_back(Duple(next->x, p->y));
+ }
+
+ p = next;
+ }
+
+ PolyItem::set(copy);
+}
+