--- /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{edge2} =} clipEdge (@var{edge}, @var{box})
+%% Clip an edge with a rectangular box.
+%%
+%% @var{edge}: [x1 y1 x2 y2],
+%% @var{box} : [xmin xmax ; ymin ymax] or [xmin xmax ymin ymax];
+%% return :
+%% @var{edge2} = [xc1 yc1 xc2 yc2];
+%%
+%% If clipping is null, return [0 0 0 0];
+%%
+%% if @var{edge} is a [nx4] array, return an [nx4] array, corresponding to each
+%% clipped edge.
+%%
+%% @seealso{edges2d, boxes2d, clipLine}
+%% @end deftypefn
+
+function edge2 = clipEdge(edge, bb)
+
+ % process data input
+ if size(bb, 1)==2
+ bb = bb';
+ end
+
+ % get limits of window
+ xmin = bb(1);
+ xmax = bb(2);
+ ymin = bb(3);
+ ymax = bb(4);
+
+
+ % convert window limits into lines
+ lineX0 = [xmin ymin xmax-xmin 0];
+ lineX1 = [xmin ymax xmax-xmin 0];
+ lineY0 = [xmin ymin 0 ymax-ymin];
+ lineY1 = [xmax ymin 0 ymax-ymin];
+
+
+ % compute outcodes of each vertex
+ p11 = edge(:,1)<xmin; p21 = edge(:,3)<xmin;
+ p12 = edge(:,1)>xmax; p22 = edge(:,3)>xmax;
+ p13 = edge(:,2)<ymin; p23 = edge(:,4)<ymin;
+ p14 = edge(:,2)>ymax; p24 = edge(:,4)>ymax;
+ out1 = [p11 p12 p13 p14];
+ out2 = [p21 p22 p23 p24];
+
+ % detect edges totally inside window -> no clip.
+ inside = sum(out1 | out2, 2)==0;
+
+ % detect edges totally outside window
+ outside = sum(out1 & out2, 2)>0;
+
+ % select edges not totally outside, and process separately edges totally
+ % inside window
+ ind = find(~(inside | outside));
+
+
+ edge2 = zeros(size(edge));
+ edge2(inside, :) = edge(inside, :);
+
+
+ for i=1:length(ind)
+ % current edge
+ iedge = edge(ind(i), :);
+
+ % compute intersection points with each line of bounding window
+ px0 = intersectLineEdge(lineX0, iedge);
+ px1 = intersectLineEdge(lineX1, iedge);
+ py0 = intersectLineEdge(lineY0, iedge);
+ py1 = intersectLineEdge(lineY1, iedge);
+
+ % create array of points
+ points = [px0; px1; py0; py1; iedge(1:2); iedge(3:4)];
+
+ % remove infinite points (edges parallel to box edges)
+ points = points(all(isfinite(points), 2), :);
+
+ % sort points by x then y
+ points = sortrows(points);
+
+ % get center positions between consecutive points
+ centers = (points(2:end,:) + points(1:end-1,:))/2;
+
+ % find the centers (if any) inside window
+ inside = find( centers(:,1)>=xmin & centers(:,2)>=ymin & ...
+ centers(:,1)<=xmax & centers(:,2)<=ymax);
+
+ % if multiple segments are inside box, which can happen due to finite
+ % resolution, only take the longest segment
+ if length(inside)>1
+ % compute delta vectors of the segments
+ dv = points(inside+1,:) - points(inside,:);
+ % compute lengths of segments
+ len = hypot(dv(:,1), dv(:,2));
+ % find index of longest segment
+ [a, I] = max(len); %#ok<ASGLU>
+ inside = inside(I);
+ end
+
+ % if one of the center points is inside box, then the according edge
+ % segment is indide box
+ if length(inside)==1
+ % restore same direction of edge
+ if iedge(1)>iedge(3) || (iedge(1)==iedge(3) && iedge(2)>iedge(4))
+ edge2(i, :) = [points(inside+1,:) points(inside,:)];
+ else
+ edge2(i, :) = [points(inside,:) points(inside+1,:)];
+ end
+ end
+
+ end % end of loop of edges
+endfunction
+
+%!demo
+%! bb = [0 100 0 100];
+%! edge = [-10 10 90 110];
+%! ec = clipEdge (edge, bb);
+%!
+%! drawBox(bb,'color','k');
+%! line(edge([1 3]),edge([2 4]),'color','b');
+%! line(ec([1 3]),ec([2 4]),'color','r','linewidth',2);
+%! axis tight
+%! v = axis ();
+%! axis(v+[0 10 -10 0])
+
+%!shared bb
+%! bb = [0 100 0 100];
+%!assert (clipEdge([20 30 80 60], bb), [20 30 80 60],1e-6);
+%!assert (clipEdge([0 30 80 60], bb), [0 30 80 60],1e-6);
+%!assert (clipEdge([0 30 100 60], bb), [0 30 100 60],1e-6);
+%!assert (clipEdge([30 0 80 100], bb), [30 0 80 100],1e-6);
+%!assert (clipEdge([0 0 100 100], bb), [0 0 100 100],1e-6);
+%!assert (clipEdge([0 100 100 0], bb), [0 100 100 0],1e-6);
+%!assert (clipEdge([20 60 120 60], bb), [20 60 100 60],1e-6);
+%!assert (clipEdge([-20 60 80 60], bb), [0 60 80 60],1e-6);
+%!assert (clipEdge([20 60 20 160], bb), [20 60 20 100],1e-6);
+%!assert (clipEdge([20 -30 20 60], bb), [20 0 20 60],1e-6);
+%!assert (clipEdge([120 30 180 60], bb), [0 0 0 0],1e-6);
+%!assert (clipEdge([-20 30 -80 60], bb), [0 0 0 0],1e-6);
+%!assert (clipEdge([30 120 60 180], bb), [0 0 0 0],1e-6);
+%!assert (clipEdge([30 -20 60 -80], bb), [0 0 0 0],1e-6);
+%!assert (clipEdge([-120 110 190 150], bb), [0 0 0 0],1e-6);
+%!assert ([50 50 100 50], clipEdge([50 50 150 50], bb),1e-6);
+%!assert ([50 50 0 50], clipEdge([50 50 -50 50], bb),1e-6);
+%!assert ([50 50 50 100], clipEdge([50 50 50 150], bb),1e-6);
+%!assert ([50 50 50 0], clipEdge([50 50 50 -50], bb),1e-6);
+%!assert ([80 50 100 70], clipEdge([80 50 130 100], bb),1e-6);
+%!assert ([80 50 100 30], clipEdge([80 50 130 0], bb),1e-6);
+%!assert ([20 50 0 70], clipEdge([20 50 -30 100], bb),1e-6);
+%!assert ([20 50 0 30], clipEdge([20 50 -30 0], bb),1e-6);
+%!assert ([50 80 70 100], clipEdge([50 80 100 130], bb),1e-6);
+%!assert ([50 80 30 100], clipEdge([50 80 0 130], bb),1e-6);
+%!assert ([50 20 70 0], clipEdge([50 20 100 -30], bb),1e-6);
+%!assert ([50 20 30 0], clipEdge([50 20 0 -30], bb),1e-6);
+%!assert ([100 50 50 50], clipEdge([150 50 50 50], bb),1e-6);
+%!assert ([0 50 50 50], clipEdge([-50 50 50 50], bb),1e-6);
+%!assert ([50 100 50 50], clipEdge([50 150 50 50], bb),1e-6);
+%!assert ([50 0 50 50], clipEdge([50 -50 50 50], bb),1e-6);
+%!assert ([100 70 80 50], clipEdge([130 100 80 50], bb),1e-6);
+%!assert ([100 30 80 50], clipEdge([130 0 80 50], bb),1e-6);
+%!assert ([0 70 20 50], clipEdge([-30 100 20 50], bb),1e-6);
+%!assert ([0 30 20 50], clipEdge([-30 0 20 50], bb),1e-6);
+%!assert ([70 100 50 80], clipEdge([100 130 50 80], bb),1e-6);
+%!assert ([30 100 50 80], clipEdge([0 130 50 80], bb),1e-6);
+%!assert ([70 0 50 20], clipEdge([100 -30 50 20], bb),1e-6);
+%!assert ([30 0 50 20], clipEdge([0 -30 50 20], bb),1e-6);
+%!assert ([0 20 80 100], clipEdge([-10 10 90 110], bb),1e-6);
+
+
+
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff