--- /dev/null
+%% Copyright (c) 2011, INRA
+%% 2004-2011, 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{d} = } edgePosition (@var{point}, @var{edge})
+%% Return position of a point on an edge
+%%
+%% POS = edgePosition(POINT, EDGE);
+%% Computes position of point POINT on the edge EDGE, relative to the
+%% position of edge vertices.
+%% EDGE has the form [x1 y1 x2 y2],
+%% POINT has the form [x y], and is assumed to belong to edge.
+%% The position POS has meaning:
+%% POS<0: POINT is located before the first vertex
+%% POS=0: POINT is located on the first vertex
+%% 0<POS<1: POINT is located between the 2 vertices (on the edge)
+%% POS=1: POINT is located on the second vertex
+%% POS<0: POINT is located after the second vertex
+%%
+%% POS = edgePosition(POINT, EDGES);
+%% If EDGES is an array of NL edges, return NL positions, corresponding to
+%% each edge.
+%%
+%% POS = edgePosition(POINTS, EDGE);
+%% If POINTS is an array of NP points, return NP positions, corresponding
+%% to each point.
+%%
+%% POS = edgePosition(POINTS, EDGES);
+%% If POINTS is an array of NP points and edgeS is an array of NL edges,
+%% return an array of [NP NL] position, corresponding to each couple
+%% point-edge.
+%%
+%% @seealso{edges2d, createEdge, onEdge}
+%% @end deftypefn
+
+function d = edgePosition(point, edge)
+
+ % number of points and of edges
+ Nl = size(edge, 1);
+ Np = size(point, 1);
+
+ if Np==Nl
+ dxl = edge(:, 3)-edge(:,1);
+ dyl = edge(:, 4)-edge(:,2);
+ dxp = point(:, 1) - edge(:, 1);
+ dyp = point(:, 2) - edge(:, 2);
+
+ d = (dxp.*dxl + dyp.*dyl)./(dxl.*dxl+dyl.*dyl);
+
+ else
+ % expand one of the array to have the same size
+ dxl = repmat((edge(:,3)-edge(:,1))', Np, 1);
+ dyl = repmat((edge(:,4)-edge(:,2))', Np, 1);
+ dxp = repmat(point(:,1), 1, Nl) - repmat(edge(:,1)', Np, 1);
+ dyp = repmat(point(:,2), 1, Nl) - repmat(edge(:,2)', Np, 1);
+
+ d = (dxp.*dxl + dyp.*dyl)./(dxl.*dxl+dyl.*dyl);
+ end
+
+endfunction
+
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff