+ switch( pt0->arc ) {
+ case ARC_CURVE:
+ if( convex(ax,ay, bx,by, cx,cy, dx,dy) >= 0 ) {
+ // s = ac thru b x bd thru c
+ intersects_at(sx,sy, ax,ay,cx,cy,bx,by, bx,by,dx,dy,cx,cy,fmx);
+ vpen->draw_smooth(bx,by, sx,sy, cx,cy);
+ break;
+ } // fall thru
+ case ARC_LINE: