makshape.m

function D = makshape
% Allows user to create a 2D shape using picks in the graphics
% window.  The shape is stored in array D where the 1st column
% is vector of x-coordinates, 2nd column is vector of y-coordinates
%
% USAGE:  D = makshape
%
% to make the shape:
%     LEFT MOUSE BUTTON   - pick a point
%     RIGHT MOUSE BUTTON  - end shape creation

clf
fx = [-10 10 10 -10 -10];
fy = [-10 -10 10 10 -10];
plot(fx,fy)                   % draws a 10 X 10 frame
axis('equal')

hold on

i = 0;
b = 1;

while b < 2     % read picks until right button
   [tx, ty, b] = ginput(1);  % read single pick point and button
   if b == 1      % left button -> store point coordinates and plot
      i = i+1;
      x(i) = tx; y(i) = ty;
      plot(tx,ty,'b+')
   end
end


D(:,1) = x';
D(:,2) = y';

x(i+1) = x(1);
y(i+1) = y(1);
plot(x,y)