INTERSECTLINEPOLYLINE Intersection points between a line and a polyline.

   P = intersectLinePolyline(LINE, POLY)
   Returns the intersection points of the lines LINE with polyline POLY. 
   LINE is a 1-by-4 row vector containing parametric representation of the
   line (in the format [x0 y0 dx dy], see the function 'createLine' for
   details). 
   POLY is a NV-by-2 array containing coordinates of the polyline vertices
   P is a K-by-2 array containing the coordinates of the K intersection
   points.

   P = intersectLinePolyline(LINE, POLY, TOL)
   Specifies the tolerance for geometric tests. Default is 1e-14.

   [P INDS] = intersectLinePolyline(...)
   Also returns the indices of edges involved in intersections. INDS is a
   K-by-1 column vector, such that P(i,:) corresponds to intersection of
   the line with the i-th edge of the polyline. If the intersection occurs
   at a polyline vertex, the index of only one of the two neighbor edges
   is returned. 
   Note that due to numerical approximations, the use of function
   'isPointOnEdge' may give results not consistent with this function.


   Examples
   % compute intersections between a square and an horizontal line
     poly = [0 0;10 0;10 10;0 10];
     line = [5 5 1 0];
     intersectLinePolyline(line, poly)
     ans =
           10     5
     % also return indices of edges
     [inters inds] = intersectLinePolyline(line, poly)
     inters =
           10     5
     inds =
           2
      
   % compute intersections between a square and a diagonal line
     poly = [0 0;10 0;10 10;0 10];
     line = [5 5 1 1];
     intersectLinePolyline(line, poly)
     ans =
            0     0
           10    10

   See Also
   lines2d, polylines2d, intersectLines, intersectLinePolygon

Package: matgeom