--- /dev/null
+%% Copyright (c) 2011, INRA
+%% 2005-2011, David Legland <david.legland@grignon.inra.fr>
+%% 2011 Adapted to Octave by Juan Pablo Carbajal <carbajal@ifi.uzh.ch>
+%%
+%% All rights reserved.
+%% (simplified BSD License)
+%%
+%% 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 COPYRIGHT HOLDER 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 copyright holder.
+
+%% -*- texinfo -*-
+%% @deftypefn {Function File} {@var{ray} = } bisector (@var{line1}, @var{line2})
+%% @deftypefnx {Function File} {@var{ray} = } bisector (@var{p1}, @var{p2}, @var{p3})
+%% Return the bisector of two lines, or 3 points.
+%%
+%% Creates the bisector of the two lines, given as [x0 y0 dx dy].
+%%
+%% create the bisector of lines (@var{p2} @var{p1}) and (@var{p2} @var{p3}).
+%%
+%% The result has the form [x0 y0 dx dy], with [x0 y0] being the origin
+%% point ans [dx dy] being the direction vector, normalized to have unit
+%% norm.
+%%
+%% @seealso{lines2d, rays2d}
+%% @end deftypefn
+
+function ray = bisector(varargin)
+
+ if length(varargin)==2
+ % two lines
+ line1 = varargin{1};
+ line2 = varargin{2};
+
+ point = intersectLines(line1, line2);
+
+ elseif length(varargin)==3
+ % three points
+ p1 = varargin{1};
+ p2 = varargin{2};
+ p3 = varargin{3};
+
+ line1 = createLine(p2, p1);
+ line2 = createLine(p2, p3);
+ point = p2;
+
+ elseif length(varargin)==1
+ % three points, given in one array
+ var = varargin{1};
+ p1 = var(1, :);
+ p2 = var(2, :);
+ p3 = var(3, :);
+
+ line1 = createLine(p2, p1);
+ line2 = createLine(p2, p3);
+ point = p2;
+ end
+
+ % compute line angles
+ a1 = lineAngle(line1);
+ a2 = lineAngle(line2);
+
+ % compute bisector angle (angle of first line + half angle between lines)
+ angle = mod(a1 + mod(a2-a1+2*pi, 2*pi)/2, pi*2);
+
+ % create the resulting ray
+ ray = [point cos(angle) sin(angle)];
+
+endfunction
+
+%!shared privpath
+%! privpath = [fileparts(which('geom2d_Contents')) filesep() 'private'];
+
+%!test
+%! addpath (privpath,'-end')
+%! p0 = [0 0];
+%! p1 = [10 0];
+%! p2 = [0 10];
+%! line1 = createLine(p0, p1);
+%! line2 = createLine(p0, p2);
+%! ray = bisector(line1, line2);
+%! assertElementsAlmostEqual([0 0], ray(1,1:2));
+%! assertAlmostEqual(pi/4, lineAngle(ray));
+%! rmpath (privpath);
+
+%!test
+%! addpath (privpath,'-end')
+%! p0 = [0 0];
+%! p1 = [10 0];
+%! p2 = [0 10];
+%! ray = bisector(p1, p0, p2);
+%! assertElementsAlmostEqual([0 0], ray(1,1:2));
+%! assertAlmostEqual(pi/4, lineAngle(ray));
+%! rmpath (privpath);
+
+%!test
+%! addpath (privpath,'-end')
+%! p0 = [0 0];
+%! p1 = [10 0];
+%! p2 = [0 10];
+%! ray = bisector([p1; p0; p2]);
+%! assertElementsAlmostEqual([0 0], ray(1,1:2));
+%! assertAlmostEqual(pi/4, lineAngle(ray));
+%! rmpath (privpath);