drawVertices

DRAWVERTICES Draw the vertices of a polygon or polyline.

   drawVertices(POLY)
   Draws the vertices of the given polygon, using pre-defined style.
   Default is to draw vertices as squares, with the first vertex filled. 

   Example
     poly = circleToPolygon([20 30 40], 16);
     drawPolygon(poly); 
     hold on; axis equal;
     drawVertices(poly);

   See also
   drawPoint, drawPolygon, drawPolyline

 ------
 Author: David Legland
 e-mail: david.legland@grignon.inra.fr
 Created: 2011-12-11,    using Matlab 7.9.0.529 (R2009b)
 Copyright 2011 INRA - Cepia Software Platform.

0001 function varargout = drawVertices(varargin)
0002 %DRAWVERTICES Draw the vertices of a polygon or polyline.
0003 %
0004 %   drawVertices(POLY)
0005 %   Draws the vertices of the given polygon, using pre-defined style.
0006 %   Default is to draw vertices as squares, with the first vertex filled.
0007 %
0008 %   Example
0009 %     poly = circleToPolygon([20 30 40], 16);
0010 %     drawPolygon(poly);
0011 %     hold on; axis equal;
0012 %     drawVertices(poly);
0013 %
0014 %   See also
0015 %   drawPoint, drawPolygon, drawPolyline
0016 %
0017 % ------
0018 % Author: David Legland
0019 % e-mail: david.legland@grignon.inra.fr
0020 % Created: 2011-12-11,    using Matlab 7.9.0.529 (R2009b)
0021 % Copyright 2011 INRA - Cepia Software Platform.
0022 
0023 % extract handle of axis to draw on
0024 if isAxisHandle(varargin{1})
0025     ax = varargin{1};
0026     varargin(1) = [];
0027 else
0028     ax = gca;
0029 end
0030 
0031 var = varargin{1};
0032 
0033 
0034 %% Manage cell arrays of polygons / polylines
0035 
0036 % case of a set of polygons stored in a cell array
0037 if iscell(var)
0038     N = length(var);
0039     h = zeros(N, 1);
0040     for i = 1:N
0041         state = ishold(gca);
0042         hold on;
0043         % check for empty polygons
0044         if ~isempty(var{i})
0045             h(i) = drawVertices(ax, var{i}, varargin{2:end});
0046         end
0047         if ~state
0048             hold off
0049         end
0050     end
0051 
0052     if nargout > 0
0053         varargout = {h};
0054     end
0055 
0056     return;
0057 end
0058 
0059 
0060 %% Parse coordinates and options
0061 
0062 % Extract coordinates of vertices
0063 if size(var, 2) > 1
0064     % first argument is a vertex array
0065     px = var(:, 1);
0066     py = var(:, 2);
0067     varargin(1) = [];
0068     
0069 elseif length(varargin) >= 2 && isnumeric(varargin{1}) && isnumeric(varargin{2})
0070     % arguments 1 and 2 correspond to x and y coordinate respectively
0071     px = varargin{1};
0072     py = varargin{2};
0073     varargin(1:2) = [];
0074     
0075 else
0076     % unknow input format
0077     error('Should specify either a N-by-2 array, or 2 N-by-1 vectors');
0078 end
0079 
0080 % concatenate input argument(s) with default options
0081 defaults = {'MarkerSize', 6};
0082 if length(varargin) == 1
0083     varargin = [varargin defaults];
0084 else
0085     varargin = [{'ks'} defaults varargin];
0086 end
0087 
0088 
0089 %% Draw the vertices
0090 
0091 % draw the vertices
0092 h = plot(ax, px, py, varargin{:});
0093 
0094 % draw the first vertex with a different style
0095 plot(ax, px(1), py(1), 'ks', 'MarkerFaceColor', 'k', 'MarkerSize', 8);
0096 
0097 % format output arg
0098 if nargout > 0
0099     varargout = {h};
0100 end