--- /dev/null
+%% Copyright (c) 2011, INRA
+%% 2010-2011, 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{edge} @var{inside}] =} clipRay (@var{ray}, @var{box})
+%% Clip a ray with a box.
+%%
+%% @var{ray} is a straight ray given as a 4 element row vector: [x0 y0 dx dy],
+%% with (x0 y0) being the origin of the ray and (dx dy) its direction
+%% vector, @var{box} is the clipping box, given by its extreme coordinates:
+%% [xmin xmax ymin ymax].
+%% The result is given as an edge, defined by the coordinates of its 2
+%% extreme points: [x1 y1 x2 y2].
+%% If the ray does not intersect the box, [NaN NaN NaN NaN] is returned.
+%%
+%% Function works also if @var{ray} is a Nx4 array, if @var{box} is a Nx4 array, or
+%% if both @var{ray} and @var{box} are Nx4 arrays. In these cases, @var{edge} is a Nx4
+%% array.
+%%
+%% @seealso{rays2d, boxes2d, edges2d, clipLine, drawRay}
+%% @end deftypefn
+
+function [edge isInside] = clipRay(ray, bb)
+
+ % adjust size of two input arguments
+ if size(ray, 1)==1
+ ray = repmat(ray, size(bb, 1), 1);
+ elseif size(bb, 1)==1
+ bb = repmat(bb, size(ray, 1), 1);
+ elseif size(ray, 1) != size(bb, 1)
+ error('bad sizes for input');
+ end
+
+ % first compute clipping of supporting line
+ edge = clipLine(ray, bb);
+
+ % detectes valid edges (edges outside box are all NaN)
+ inds = find(isfinite(edge(:, 1)));
+
+ % compute position of edge extremities relative to the ray
+ pos1 = linePosition(edge(inds,1:2), ray(inds,:));
+ pos2 = linePosition(edge(inds,3:4), ray(inds,:));
+
+ % if first point is before ray origin, replace by origin
+ edge(inds(pos1<0), 1:2) = ray(inds(pos1<0), 1:2);
+
+ % if last point of edge is before origin, set all edge to NaN
+ edge(inds(pos2<0), :) = NaN;
+
+ % eventually returns result about inside or outside
+ if nargout>1
+ isInside = isfinite(edge(:,1));
+ end
+
+endfunction
+
+%!shared bb
+%! bb = [0 100 0 100];
+
+%!test % inside
+%! origin = [30 40];
+%! direction = [10 0];
+%! ray = [origin direction];
+%! expected = [30 40 100 40];
+%! assert (expected, clipRay(ray, bb), 1e-6);
+
+%!test % outside
+%! origin = [30 140];
+%! direction = [10 0];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % line inside, but ray outside
+%! origin = [130 40];
+%! direction = [10 0];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % inside
+%! origin = [30 40];
+%! direction = [-10 0];
+%! ray = [origin direction];
+%! expected = [30 40 0 40];
+%! assert (expected, clipRay(ray, bb), 1e-6);
+
+%!test % outside
+%! origin = [30 140];
+%! direction = [-10 0];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % line inside, but ray outside
+%! origin = [-30 40];
+%! direction = [-10 0];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % inside
+%! origin = [30 40];
+%! direction = [0 10];
+%! ray = [origin direction];
+%! expected = [30 40 30 100];
+%! assert (expected, clipRay(ray, bb), 1e-6);
+
+%!test % outside
+%! origin = [130 40];
+%! direction = [0 10];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % line inside, but ray outside
+%! origin = [30 140];
+%! direction = [0 10];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % inside
+%! origin = [30 40];
+%! direction = [0 -10];
+%! ray = [origin direction];
+%! expected = [30 40 30 0];
+%! assert (expected, clipRay(ray, bb), 1e-6);
+
+%!test % outside
+%! origin = [130 40];
+%! direction = [0 -10];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test % line inside, but ray outside
+%! origin = [30 -40];
+%! direction = [0 -10];
+%! ray = [origin direction];
+%! assert (sum(isnan(clipRay(ray, bb)))==4);
+
+%!test
+%! origins = [30 40;30 40;30 140;130 40];
+%! directions = [10 0;0 10;10 0;0 10];
+%! rays = [origins directions];
+%! expected = [30 40 100 40;30 40 30 100;NaN NaN NaN NaN;NaN NaN NaN NaN];
+%! clipped = clipRay(rays, bb);
+%! assert (expected, clipped, 1e-6);
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff