drawLine

DRAWLINE Draw a straight line clipped by the current axis.

   drawLine(LINE);
   Draws the line LINE on the current axis, by using current axis to clip
   the line. 

   drawLine(LINE, PARAM, VALUE);
   Specifies drawing options.

   H = drawLine(...)
   Returns a handle to the created line object. If clipped line is not
   contained in the axis, the function returns -1.
   
   Example
     figure; hold on; axis equal;
     axis([0 100 0 100]);
     drawLine([30 40 10 20]);
     drawLine([30 40 20 -10], 'Color', 'm', 'LineWidth', 2);
     drawLine([-30 140 10 20]);

   See also:
   lines2d, createLine, drawEdge

   ---------
   author : David Legland
   INRA - TPV URPOI - BIA IMASTE
   created the 31/10/2003.

0001 function varargout = drawLine(lin, varargin)
0002 %DRAWLINE Draw a straight line clipped by the current axis.
0003 %
0004 %   drawLine(LINE);
0005 %   Draws the line LINE on the current axis, by using current axis to clip
0006 %   the line.
0007 %
0008 %   drawLine(LINE, PARAM, VALUE);
0009 %   Specifies drawing options.
0010 %
0011 %   H = drawLine(...)
0012 %   Returns a handle to the created line object. If clipped line is not
0013 %   contained in the axis, the function returns -1.
0014 %
0015 %   Example
0016 %     figure; hold on; axis equal;
0017 %     axis([0 100 0 100]);
0018 %     drawLine([30 40 10 20]);
0019 %     drawLine([30 40 20 -10], 'Color', 'm', 'LineWidth', 2);
0020 %     drawLine([-30 140 10 20]);
0021 %
0022 %   See also:
0023 %   lines2d, createLine, drawEdge
0024 %
0025 %   ---------
0026 %   author : David Legland
0027 %   INRA - TPV URPOI - BIA IMASTE
0028 %   created the 31/10/2003.
0029 %
0030 
0031 %   HISTORY
0032 %   25/05/2004 add support for multiple lines (loop)
0033 %   23/05/2005 add support for arguments
0034 %   03/08/2010 bug for lines outside box (thanks to Reto Zingg)
0035 %   04/08/2010 rewrite using clipLine
0036 %   2011-10-11 add management of axes handle
0037 
0038 % extract handle of axis to draw in
0039 if isAxisHandle(lin)
0040     ax = lin;
0041     lin = varargin{1};
0042     varargin(1) = [];
0043 else
0044     ax = gca;
0045 end
0046 
0047 % default style for drawing lines
0048 if length(varargin) ~= 1
0049     varargin = [{'color', 'b'}, varargin];
0050 end
0051 
0052 % extract bounding box of the current axis
0053 xlim = get(ax, 'xlim');
0054 ylim = get(ax, 'ylim');
0055 
0056 % clip lines with current axis box
0057 clip = clipLine(lin, [xlim ylim]);
0058 ok   = isfinite(clip(:,1));
0059 
0060 % initialize result array to invalide handles
0061 h = -1 * ones(size(lin, 1), 1);
0062 
0063 % draw valid lines
0064 h(ok) = plot(ax, clip(ok, [1 3])', clip(ok, [2 4])', varargin{:});
0065 
0066 % return line handle if needed
0067 if nargout > 0
0068     varargout = {h};
0069 end