createEdge3d

CREATEEDGE3D Create an edge between two 3D points, or from a 3D line.

   E = createEdge3d(P1, P2)
   Creates the 3D edge joining the two points P1 and P2.

   E = createEdge3d(LIN)
   Creates the 3D edge with same origin and same direction vector as the
   3D line LIN.

   Example
     p1 = [1 1 1];
     p2 = [3 4 5];
     edge = createEdge3d(p1, p2);
     edgeLength3d(edge)
     ans =
         5.3852
   
   See also
     edges3d, drawEdge3d, clipEdge3d, edgelength3d

0001 function edge = createEdge3d(varargin)
0002 %CREATEEDGE3D Create an edge between two 3D points, or from a 3D line.
0003 %
0004 %   E = createEdge3d(P1, P2)
0005 %   Creates the 3D edge joining the two points P1 and P2.
0006 %
0007 %   E = createEdge3d(LIN)
0008 %   Creates the 3D edge with same origin and same direction vector as the
0009 %   3D line LIN.
0010 %
0011 %   Example
0012 %     p1 = [1 1 1];
0013 %     p2 = [3 4 5];
0014 %     edge = createEdge3d(p1, p2);
0015 %     edgeLength3d(edge)
0016 %     ans =
0017 %         5.3852
0018 %
0019 %   See also
0020 %     edges3d, drawEdge3d, clipEdge3d, edgelength3d
0021  
0022 % ------
0023 % Author: David Legland
0024 % e-mail: david.legland@inra.fr
0025 % Created: 2018-08-29,    using Matlab 9.4.0.813654 (R2018a)
0026 % Copyright 2018 INRA - Cepia Software Platform.
0027 
0028 
0029 if nargin == 1
0030     % Only one input parameter. Assumes it corresponds to a 3D line with
0031     % 6 params.
0032     var = varargin{1};
0033     
0034     if size(var, 2) ~= 6
0035         error('single input must have 6 columns');
0036     end
0037     
0038     % converts 3D line into 3D edge
0039     edge = zeros(size(var));
0040     edge(:, 1:3) = var(:, 1:3);
0041     edge(:, 4:6) = edge(:, 1:3) + var(:,4:6);
0042     
0043 elseif nargin == 2    
0044     % 2 input parameters correspond to two 3D points
0045     
0046     % extract the two arguments
0047     v1 = varargin{1};
0048     v2 = varargin{2};
0049     
0050     if size(v1, 2) ~= 3 || size(v2, 2) ~= 3
0051         error('Input points must be arrays with 3 columns');
0052     end
0053     
0054     % first input parameter is first point, and second input is the
0055     % second point. Allows multiple points.
0056     n1 = size(v1, 1);
0057     n2 = size(v2, 1);
0058     if n1 == n2
0059         edge = [v1 v2];
0060     elseif n1 == 1 || n2 == 1
0061         edge = [repmat(v1, n2, 1) repmat(v2, n1, 1)];
0062     end
0063     
0064 else
0065     error('Wrong number of arguments in ''%s''', mfilename);
0066 end