nrbline.m

非均匀有理B样条的matlab程序

function curve = nrbline(p1,p2)
% 
% Function Name:
% 
%   nrbline - Construct a straight line.
% 
% Calling Sequence:
% 
%   crv = nrbline()
%   crv = nrbline(p1,p2)
% 
% Parameters:
% 
% p1		: 2D or 3D cartesian coordinate of the start point.
% 
% p2            : 2D or 3D cartesian coordinate of the end point.
% 
% crv		: NURBS curve for a straight line.
% 
% Description:
% 
%   Constructs NURBS data structure for a straight line. If no rhs 
%   coordinates are included the function returns a unit straight
%   line along the x-axis.

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

coefs = [zeros(3,2); ones(1,2)];

if nargin < 2
  coefs(1,2) = 1.0;  
else
  coefs(1:length(p1),1) = p1(:);    
  coefs(1:length(p2),2) = p2(:);
end

curve = nrbmak(coefs, [0 0 1 1]);