[metapost] Re: all intersections between two paths

Boguslaw Jackowski bop at bop.com.pl
Fri Jan 7 10:20:08 CET 2005

BJ> two B\'ezier segments without selfintersections can
BJ> cross each other at 7 points (which is a simple consequence of the theorem
BJ> stated by Dan, that two segments can have at most 9 intersection points).

Neither simple, nor consequence, nor true:

Dan> Here's one without self-intersections:
Dan> beginfig(0);
Dan>   path p,q;
Dan>    p:=(-10, -100).. controls (-10,600) and (10,-500)..(10,100);
Dan>    q:= p rotated 90;
Dan>   draw p; draw q;
Dan> endfig;


-- Jacko

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