Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / geometry-1.5.0 / polygons2d / supportFunction.m

diff --git a/octave_packages/geometry-1.5.0/polygons2d/supportFunction.m b/octave_packages/geometry-1.5.0/polygons2d/supportFunction.m
new file mode 100644 (file)
index 0000000..7936aae
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+++ b/octave_packages/geometry-1.5.0/polygons2d/supportFunction.m
@@ -0,0 +1,72 @@
+%% 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{h} = } suppportFunction (@var{polygon})
+%% @deftypefnx {Function File} {@var{h} = } suppportFunction (@var{polygon}, @var{n})
+%% @deftypefnx {Function File} {@var{h} = } suppportFunction (@var{polygon}, @var{v})
+%% Compute support function of a polygon
+%%
+%%   H = supportFunction(POLYGON, N)
+%%   uses N points for suport function approximation
+%%
+%%   H = supportFunction(POLYGON)
+%%   assume 24 points for approximation
+%%
+%%   H = supportFunction(POLYGON, V)
+%%   where V is a vector, uses vector V of angles to compute support
+%%   function.
+%%
+%% @seealso{convexification}
+%% @end deftypefn
+
+function h = supportFunction(polygon, varargin)
+  N = 24;
+  u = (0:2*pi/N:2*pi*(1-1/N)).';
+
+  if length(varargin)==1
+      var = varargin{1};
+      if length(var)==1
+          N = var;
+          u = (0:2*pi/N:2*pi*(1-1/N)).';
+      else
+          u = var(:);
+      end
+  end
+
+
+  h = zeros(size(u));
+
+  for i=1:length(u)
+
+      v = repmat([cos(u(i)) sin(u(i))], [size(polygon, 1), 1]);
+
+      h(i) = max(dot(polygon, v, 2));
+  end
+
+endfunction