demogeom.m

非均匀有理B样条的matlab程序

function demogeom
% Demonstration of how to construct a 2D geometric  
% shape from a piece-wise set of NURBSs
%

% D.M. Spink
% Copyright (c) 2000.

coefs = [0.0 7.5 15.0 25.0 35.0 30.0 27.5 30.0;
         0.0 2.5  0.0 -5.0  5.0 15.0 22.5 30.0];
knots = [0.0 0.0 0.0 1/6 1/3 1/2 2/3 5/6 1.0 1.0 1.0];

% Geometric boundary curve
geom = [
nrbmak(coefs,knots)
nrbline([30.0 30.0],[20.0 30.0])
nrbline([20.0 30.0],[20.0 20.0])
nrbcirc(10.0,[10.0 20.0],1.5*pi,0.0)
nrbline([10.0 10.0],[0.0 10.0])
nrbline([0.0 10.0],[0.0 0.0])
nrbcirc(5.0,[22.5 7.5])
];

ng = length(geom);
for i = 1:ng
  nrbplot(geom(i),50);
  hold on;
end
hold off;
axis equal;
title('2D Geometry formed by a series of NURBS curves');