how to change the dimension of ellipsoid after orientation

Question

ankit agrawal 2021-8-10

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/895532-how-to-change-the-dimension-of-ellipsoid-after-orientation

I have created an ellipsoid, plane and long axis line in step 1. Step 2 plane becomes horizontal to xy plane and ellispoid rotate along the plane. Now in step 3, I want to change the dimension of ellipsoid (fat ellipsoid along Z) but keep the orientation same something like hand drawn red ellipse in step 2. How should I achieve this? This is the code used to generate the following picture.

viewvector=[-68,18];
data=[1 1 0; -1, 1, 0; -1,-1,0;  1,-1,0];
longaxisline=[0,-2,0;0,2,0];
theta=120; 
theta1=60; 
direction = [1 0 0];
subplot(2,3,1))
[x,y,z]=ellipsoid(0,0,0,0.5,1,0.25,50);
h=surfl(x,y,z);
set(h,'facealpha',0.5)
shading interp 
xlabel('x')
ylabel('y')
zlabel('z')
hold on 
s=patch(data(:,1)',data(:,2)',data(:,3)') ;
rotate(s,direction,theta)
plot3(longaxisline(:,1),longaxisline(:,2),longaxisline(:,3),'b.-')
%s1=patch(data(:,1)',data(:,2)',data(:,3)');
axis image 
view(viewvector)
%set(gca,'visible','off')
if j==1
    title('step 1')
end
subplot(2,3,2) 
h=surfl(x,y,z);
rotate(h,direction,theta)
set(h,'facealpha',0.5)
shading interp 
xlabel('x')
ylabel('y')
zlabel('z')
hold on 
s=patch(data(:,1)',data(:,2)',data(:,3)') ;
rotate(s,direction,0)
axis image
view(viewvector)
if j==1
    title('step 2')
end
pp=longaxisline*RotationMatrix_X(theta1*pi/180); plot3(pp(:,1),pp(:,2),pp(:,3),'b.-')
%pp=longaxisline*RotationMatrix_Y(theta*pi/180); plot3(pp(:,1),pp(:,2),pp(:,3),'k-')
%pp=longaxisline*RotationMatrix_Z(theta*pi/180); plot3(pp(:,1),pp(:,2),pp(:,3),'r.-')
subplot(2,3,3) 
[x,y,z]=ellipsoid(0,0,0,0.5,0.5,0.5,50);
%[x,y,z]=ellipsoid(0,0,0,0.5,1,0.25,50);
h=surf(x,y,z);
T = hgtransform('Parent',gca);
h.Parent=T;
T.Matrix=makehgtform('xrotate',theta*pi/180,'translate',[0 0 0]);
% h=surfl(x,y,z);
% rotate(h,direction,theta)
set(h,'facealpha',0.5)
shading interp 
xlabel('x')
ylabel('y')
zlabel('z')
hold on 
s=patch(data(:,1)',data(:,2)',data(:,3)') ;
rotate(s,direction,0)
axis image 
view(viewvector)
if j==1
    title('step 3')
end
pp=longaxisline*RotationMatrix_X(theta1*pi/180); plot3(pp(:,1),pp(:,2),pp(:,3),'b.-')