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, clipLine

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, clipLine
0024 %
0025 
0026 % ------
0027 % Author: David Legland
0028 % E-mail: david.legland@inrae.fr
0029 % Created: 2003-10-31
0030 % Copyright 2003-2024 INRA - TPV URPOI - BIA IMASTE
0031 
0032 isLine3d = @(x) validateattributes(x,{'numeric'},...
0033     {'nonempty','nonnan','real','finite','size',[nan,4]});
0034 defOpts.Color = 'b';
0035 [ax, lin, varargin] = ...
0036     parseDrawInput(lin, isLine3d, 'line', defOpts, varargin{:});
0037 
0038 % extract bounding box of the current axis
0039 xlim = get(ax, 'xlim');
0040 ylim = get(ax, 'ylim');
0041 
0042 % clip lines with current axis box
0043 clip = clipLine(lin, [xlim ylim]);
0044 ok   = isfinite(clip(:,1));
0045 
0046 % initialize result array to invalide handles
0047 h = -1 * ones(size(lin, 1), 1);
0048 
0049 % draw valid lines
0050 h(ok) = plot(ax, clip(ok, [1 3])', clip(ok, [2 4])', varargin{:});
0051 
0052 % return line handle if needed
0053 if nargout > 0
0054     varargout = {h};
0055 end