Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / nurbs-1.3.6 / nrbrect.m

diff --git a/octave_packages/nurbs-1.3.6/nrbrect.m b/octave_packages/nurbs-1.3.6/nrbrect.m
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+++ b/octave_packages/nurbs-1.3.6/nrbrect.m
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+function curve = nrbrect(w,h)
+% 
+% NRBRECT: Construct NURBS representation of a rectangular curve.
+% 
+% Calling Sequence:
+% 
+%   crv = nrbrect()
+%   crv = nrbrect(size)
+%   crv = nrbrect(width, height)
+% 
+% INPUT:
+% 
+%   size       : Size of the square (width = height).
+% 
+%   width      : Width of the rectangle (along x-axis).
+% 
+%   height     : Height of the rectangle (along y-axis).
+%
+% OUTPUT:
+%
+%   crv                : NURBS curve, see nrbmak. 
+%  
+% 
+% Description:
+% 
+%   Construct a rectangle or square in the x-y plane with the bottom
+%   lhs corner at (0,0,0). If no rhs arguments provided the function
+%   constructs a unit square.
+%
+%    Copyright (C) 2000 Mark Spink
+%
+%    This program is free software: you can redistribute it and/or modify
+%    it under the terms of the GNU General Public License as published by
+%    the Free Software Foundation, either version 2 of the License, or
+%    (at your option) any later version.
+
+%    This program is distributed in the hope that it will be useful,
+%    but WITHOUT ANY WARRANTY; without even the implied warranty of
+%    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%    GNU General Public License for more details.
+%
+%    You should have received a copy of the GNU General Public License
+%    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+if nargin < 1
+   w = 1;
+   h = 1;
+end
+
+if nargin < 2
+   h = w;
+end
+
+coefs  = [0 w w w w 0 0 0;
+          0 0 0 h h h h 0;
+          0 0 0 0 0 0 0 0;
+          1 1 1 1 1 1 1 1];
+
+knots  = [0 0 0.25 0.25 0.5 0.5 0.75 0.75 1 1];
+
+curve = nrbmak(coefs, knots);
+
+end
+
+%!demo
+%! crv = nrbtform(nrbrect(2,1), vecrotz(deg2rad(35)));
+%! nrbplot(crv,4);
+%! axis equal
+%! title('Construction and rotation of a rectangular curve.');
+%! hold off
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