/**********************************************************************
* TriStrip:
**********************************************************************/
Bface*
TriStrip::backup_strip(Bface* f, Bvert*& a)
{
// we'd like to draw a triangle strip starting at the
// given triangle and proceeding "forward." but to get
// the most bang for the buck, we'll first "backup" over
// as many triangles as possible to find a starting place
// from which we can generate a longer strip.
assert(!f->flag());
mark_face(f);
Bface* ret = f;
Bvert* b = f->next_vert_ccw(a);
Bedge* e;
int i = 0;
while((e = f->edge_from_vert((i%2) ? b : a)) &&
e->consistent_orientation() &&
e->is_crossable() &&
(f = e->other_face(f)) &&
is_cleared(f)) {
mark_face(f);
ret = f;
Bvert* d = f->other_vertex(a,b);
b = a;
a = d;
i++;
}
_orientation = ((i%2) != 0);
return ret;
}
