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diff --git a/octave_packages/geometry-1.5.0/polygons2d/expandPolygon.m b/octave_packages/geometry-1.5.0/polygons2d/expandPolygon.m
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+## Copyright (C) 2003-2011 David Legland <david.legland@grignon.inra.fr>
+## Copyright (C) 2012 Adapted to Octave by Juan Pablo Carbajal <carbajal@ifi.uzh.ch>
+## All rights reserved.
+##
+## Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are met:
+##
+##     1 Redistributions of source code must retain the above copyright notice,
+##       this list of conditions and the following disclaimer.
+##     2 Redistributions in binary form must reproduce the above copyright
+##       notice, this list of conditions and the following disclaimer in the
+##       documentation and/or other materials provided with the distribution.
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ''AS IS''
+## AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+## IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+## ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+## ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+## DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+## SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+## CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+## OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+##
+## The views and conclusions contained in the software and documentation are
+## those of the authors and should not be interpreted as representing official
+## policies, either expressed or implied, of the copyright holders.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{loops} = } expandPolygon (@var{poly}, @var{dist})
+##  Expand a polygon by a given (signed) distance
+##
+##   Associates to each edge of the polygon @var{poly} the parallel line located
+##   at distance @var{dist} from the current edge, and compute intersections with
+##   neighbor parallel lines. The resulting polygon is simplified to remove
+##   inner "loops", and can be disconnected.
+##   The result is a cell array, each cell containing a simple linear ring.
+##
+##   This is a kind of dilation, but behaviour on corners is different.
+##   This function keeps angles of polygons, but there is no direct relation
+##   between length of 2 polygons.
+##
+##   It is also possible to specify negative distance, and get all points
+##   inside the polygon. If the polygon is convex, the result equals
+##   morphological erosion of polygon by a ball with radius equal to the
+##   given distance.
+##
+## @seealso{polygons2d}
+## @end deftypefn
+
+function loops = expandPolygon(poly, dist)
+
+  # eventually copy first point at the end to ensure closed polygon
+  if sum(poly(end, :)==poly(1,:))~=2
+      poly = [poly; poly(1,:)];
+  end
+
+  # number of vertices of the polygon
+  N = size(poly, 1)-1;
+
+  # find lines parallel to polygon edges located at distance DIST
+  lines = zeros(N, 4);
+  for i=1:N
+      side = createLine(poly(i,:), poly(i+1,:));
+      lines(i, 1:4) = parallelLine(side, dist);
+  end
+
+  # compute intersection points of consecutive lines
+  lines = [lines;lines(1,:)];
+  poly2 = zeros(N, 2);
+  for i=1:N
+      poly2(i,1:2) = intersectLines(lines(i,:), lines(i+1,:));
+  end
+
+  # split result polygon into set of loops (simple polygons)
+  loops = polygonLoops(poly2);
+
+  # keep only loops whose distance to original polygon is correct
+  distLoop = zeros(length(loops), 1);
+  for i=1:length(loops)
+      distLoop(i) = distancePolygons(loops{i}, poly);
+  end
+  loops = loops(abs(distLoop-abs(dist))<abs(dist)/1000);
+
+endfunction