distancePointPolygon

DISTANCEPOINTPOLYGON Shortest distance between a point and a polygon.

   DIST = distancePointPolygon(POINT, POLYGON)
   Computes the shortest distance between the point POINT and the polygon
   given by POLYGON. POINT is a 1-by-2 row vector, and POLYGON is a N-by-2
   array containing vertex coordinates.
   The distance is computed as the minimal distance to the boundary edges.

   Example
     % Computes the distance between a point and a square
     square = [0 0; 10 0;10 10;0 10];
     p0 = [16 3];
     distancePointPolygon(p0, square)
     ans =
          6

   See also
   polygons2d, points2d, distancePointPolyline, distancePointEdge,
   projPointOnPolyline

0001 function minDist = distancePointPolygon(point, poly)
0002 %DISTANCEPOINTPOLYGON Shortest distance between a point and a polygon.
0003 %
0004 %   DIST = distancePointPolygon(POINT, POLYGON)
0005 %   Computes the shortest distance between the point POINT and the polygon
0006 %   given by POLYGON. POINT is a 1-by-2 row vector, and POLYGON is a N-by-2
0007 %   array containing vertex coordinates.
0008 %   The distance is computed as the minimal distance to the boundary edges.
0009 %
0010 %   Example
0011 %     % Computes the distance between a point and a square
0012 %     square = [0 0; 10 0;10 10;0 10];
0013 %     p0 = [16 3];
0014 %     distancePointPolygon(p0, square)
0015 %     ans =
0016 %          6
0017 %
0018 %   See also
0019 %   polygons2d, points2d, distancePointPolyline, distancePointEdge,
0020 %   projPointOnPolyline
0021 %
0022 
0023 % ------
0024 % Author: David Legland
0025 % e-mail: david.legland@nantes.inra.fr
0026 % Created: 2009-04-30,    using Matlab 7.7.0.471 (R2008b)
0027 % Copyright 2009 INRA - Cepia Software Platform.
0028 
0029 % eventually copy first point at the end to ensure closed polygon
0030 if sum(poly(end, :) == poly(1,:)) ~= 2
0031     poly = [poly; poly(1,:)];
0032 end
0033 
0034 % call to distancePointPolyline
0035 minDist = distancePointPolyline(point, poly);