B樣条曲线正算反算贝塞尔曲线拼接曲面车身CAD作业答案.doc

贝塞尔曲线的拼接 % By lyqmathclc; clear all; close all;p=[1 2; 4 8; 6 15; 9 18];p=p;t=linspace(0,1,200);n=size(p,2)-1;r=0;for k=0:n r=r+prod(1:n)/(prod(1:k)*prod(1:n-k))*p(:,k+1)*(t.^k.*(1-t).^(n-k));endplot(r(1,:),r(2,:),p(1,:),p(2,:),-or) B样条曲线的正算 function Byt8(p0,p1,p2,p3,p4,p5,p6,p7) t=0:0.001:1; %m=[-1 3 -3 1;3 -6 3 0;-3 0 3 0;1 4 1 0]; x=p0(1)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p1(1)*(1/6)*(3*t.^3-6*t.^2+4)... +p2(1)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p3(1)*(1/6)*t.^3; y=p0(2)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p1(2)*(1/6)*(3*t.^3-6*t.^2+4)... +p2(2)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p3(2)*(1/6)*t.^3; %plot([p0(1) p1(1) p2(1) p3(1)],[p0(2) p1(2) p2(2) p3(2)]); hold on; plot(x,y,r); x=p1(1)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p2(1)*(1/6)*(3*t.^3-6*t.^2+4)... +p3(1)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p4(1)*(1/6)*t.^3; y=p1(2)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p2(2)*(1/6)*(3*t.^3-6*t.^2+4)... +p3(2)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p4(2)*(1/6)*t.^3; %plot([p0(1) p1(1) p2(1) p3(1)],[p0(2) p1(2) p2(2) p3(2)]); hold on; plot(x,y,r); x=p2(1)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p3(1)*(1/6)*(3*t.^3-6*t.^2+4)... +p4(1)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p5(1)*(1/6)*t.^3; y=p2(2)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p3(2)*(1/6)*(3*t.^3-6*t.^2+4)... +p4(2)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p5(2)*(1/6)*t.^3; %plot([p0(1) p1(1) p2(1) p3(1)],[p0(2) p1(2) p2(2) p3(2)]); hold on; plot(x,y,r); x=p3(1)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p4(1)*(1/6)*(3*t.^3-6*t.^2+4)... +p5(1)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p6(1)*(1/6)*t.^3; y=p3(2)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p4(2)*(1/6)*(3*t.^3-6*t.^2+4)... +p5(2)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p6(2)*(1/6)*t.^3; %plot([p0(1) p1(1) p2(1) p3(1)],[p0(2) p1(2) p2(2) p3(2)]); hold on; plot(x,y,r); x=p4(1)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p5(1)*(1/6)*(3*t.^3-6*t.^2+4)... +p6(1)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p7(1)*(1/6)*t.^3; y=p4(2)*(1/6)*(-t.^3+3*t.^2-3*t+1)+p5(2)*(1/6)*(3*t.^3-6*t.^2+4)... +p6(2)*(1/6)*(-3*t.^3+3*t.^2+3*t+1)+p7(2)*(1/6)*t.^3; %plot([p0(1) p1(1) p2(1) p3(1)],[p0(2) p1(2) p2(2) p3(2)]); hol