RAYS2D  Description of functions operating on planar rays.

   A ray is defined by a point (its origin), and a vector (its
   direction). The different parameters are bundled into a row vector:
   RAY = [x0 y0 dx dy];

   The ray contains all the points (x,y) such that:
   x = x0 + t*dx
   y = y0 + t*dy;
   for all t>0

   Contrary to a (straight) line, the points located before the origin do
   not belong to the ray.
   However, as rays and lines have the same representation, some functions
   working on lines are also working on rays (like 'transformLine').

   See also:
   points2d, vectors2d, lines2d
   createRay, bisector, isPointOnRay
   clipRay, drawRay

 ------
 Author: David Legland
 e-mail: david.legland@grignon.inra.fr
 Created: 2008-10-13,    using Matlab 7.4.0.287 (R2007a)
 Copyright 2008 INRA - BIA PV Nantes - MIAJ Jouy-en-Josas.

Package: matgeom