drawEdge

DRAWEDGE Draw an edge given by 2 points.
   
   drawEdge(x1, y1, x2, y2);
   draw an edge between the points (x1 y1) and  (x2 y2).

   drawEdge([x1 y1 x2 y2]) ;
   drawEdge([x1 y1], [x2 y2]);
   specify data either as bundled edge, or as 2 points

   The function supports 3D edges:
   drawEdge([x1 y1 z1 x2 y2 z2]);
   drawEdge([x1 y1 z1], [x2 y2 z2]);
   drawEdge(x1, y1, z1, x2, y2, z2);

   Arguments can be single values or array of size [N*1]. In this case,
   the function draws multiple edges.

   H = drawEdge(..., OPT), with OPT being a set of pairwise options, can
   specify color, line width and so on...

   H = drawEdge(...) return handle(s) to created edges(s)

   See also:
   edges2d, drawCenteredEdge, drawLine

0001 function varargout = drawEdge(varargin)
0002 %DRAWEDGE Draw an edge given by 2 points.
0003 %
0004 %   drawEdge(x1, y1, x2, y2);
0005 %   draw an edge between the points (x1 y1) and  (x2 y2).
0006 %
0007 %   drawEdge([x1 y1 x2 y2]) ;
0008 %   drawEdge([x1 y1], [x2 y2]);
0009 %   specify data either as bundled edge, or as 2 points
0010 %
0011 %   The function supports 3D edges:
0012 %   drawEdge([x1 y1 z1 x2 y2 z2]);
0013 %   drawEdge([x1 y1 z1], [x2 y2 z2]);
0014 %   drawEdge(x1, y1, z1, x2, y2, z2);
0015 %
0016 %   Arguments can be single values or array of size [N*1]. In this case,
0017 %   the function draws multiple edges.
0018 %
0019 %   H = drawEdge(..., OPT), with OPT being a set of pairwise options, can
0020 %   specify color, line width and so on...
0021 %
0022 %   H = drawEdge(...) return handle(s) to created edges(s)
0023 %
0024 %   See also:
0025 %   edges2d, drawCenteredEdge, drawLine
0026 %
0027 
0028 %   ---------
0029 %   author : David Legland
0030 %   INRA - TPV URPOI - BIA IMASTE
0031 %   created the 31/10/2003.
0032 %
0033 
0034 %   HISTORY
0035 %   19/02/2004 add support for arrays of edges.
0036 %   31/03/2004 change format of edges to [P1 P2] and variants.
0037 %   28/11/2004 add support for 3D edges
0038 %   01/08/2005 add support for drawing options
0039 %   31/05/2007 update doc, and code makeup
0040 %   03/08/2010 re-organize code
0041 
0042 % separate edge and optional arguments
0043 [ax, edge, options] = parseInputArguments(varargin{:});
0044 
0045 % save hold state
0046 holdState = ishold(ax);
0047 hold(ax, 'on');
0048 
0049 % draw the edges
0050 if size(edge, 2) == 4
0051     h = drawEdge_2d(ax, edge, options);
0052 else
0053     h = drawEdge_3d(ax, edge, options);
0054 end
0055 
0056 % restore hold state
0057 if ~holdState
0058     hold(ax, 'off');
0059 end
0060 
0061 % eventually return handle to created edges
0062 if nargout > 0
0063     varargout = {h};
0064 end
0065 
0066 
0067 function h = drawEdge_2d(ax, edge, options)
0068 
0069 h = -1 * ones(size(edge, 1), 1);
0070 
0071 for i = 1:size(edge, 1)
0072     if isnan(edge(i,1))
0073         continue;
0074     end
0075     
0076     h(i) = plot(ax, edge(i, [1 3]), edge(i, [2 4]), options{:});
0077 end
0078 
0079 
0080 function h = drawEdge_3d(ax, edge, options)
0081 
0082 h = -1 * ones(size(edge, 1), 1);
0083 
0084 for i = 1:size(edge, 1)
0085     if isnan(edge(i,1))
0086         continue;
0087     end
0088     
0089     h(i) = plot3(ax, edge(i, [1 4]), edge(i, [2 5]), edge(i, [3 6]), options{:});
0090 end
0091 
0092     
0093 function [ax, edge, options] = parseInputArguments(varargin)
0094 
0095 % extract handle of axis to draw on
0096 if isAxisHandle(varargin{1})
0097     ax = varargin{1};
0098     varargin(1) = [];
0099 else
0100     ax = gca;
0101 end
0102 
0103 % find the number of arguments defining edges
0104 nbVal = 0;
0105 for i = 1:length(varargin)
0106     if isnumeric(varargin{i})
0107         nbVal = nbVal+1;
0108     else
0109         % stop at the first non-numeric value
0110         break;
0111     end
0112 end
0113 
0114 % extract drawing options
0115 options = varargin(nbVal+1:end);
0116 
0117 % ensure drawing options have correct format
0118 if length(options) == 1
0119     options = [{'color'}, options];
0120 end
0121 
0122 % extract edges characteristics
0123 switch nbVal
0124     case 1
0125         % all parameters in a single array
0126         edge = varargin{1};
0127         
0128     case 2
0129         % parameters are two points, or two arrays of points, of size N*2.
0130         p1 = varargin{1};
0131         p2 = varargin{2};
0132         edge = [p1 p2];
0133         
0134     case 4
0135         % parameters are 4 parameters of the edge : x1 y1 x2 and y2
0136         edge = [varargin{1} varargin{2} varargin{3} varargin{4}];
0137         
0138     case 6
0139         % parameters are 6 parameters of the edge : x1 y1 z1 x2 y2 and z2
0140         edge = [varargin{1} varargin{2} varargin{3} varargin{4} varargin{5} varargin{6}];
0141         
0142     otherwise
0143         error('drawEdge:WrongNumberOfParameters', 'Wrong number of parameters');
0144 end