how do i plot control net?

does anyone know how do i plot the control net surrounding the cylinder as shown in the picture above? i tried plot3d but it only appears like the picture attached below

Answer 1

[Ayush]

Hi @NurFadhilah Samsuddin,

You can plot the control net surrounding the cylinder using "plot3" function itself.

Here's the code for your reference:

% Define the cylinder parameters
outerRadius = 1;    
innerRadius = 0.5;  
height = 2;         

% Define the number of control points in each direction
numPointsX = 10; 
numPointsY = 10;  

% Generate the control net coordinates
theta = linspace(0, 2*pi, numPointsX);  
z = linspace(0, height, numPointsY);     
[Theta, Z] = meshgrid(theta, z);         
X = outerRadius * cos(Theta);            
Y = outerRadius * sin(Theta); 

% Plot the control net
figure;
plot3(X, Y, Z, 'b.');  % Plot control points
hold on;
mesh(X, Y, Z);         % Plot mesh connecting control points

% Draw the outer cylinder
[Xcyl, Ycyl, Zcyl] = cylinder(outerRadius, numPointsX);
Zcyl = Zcyl * height;
surf(Xcyl, Ycyl, Zcyl, 'FaceAlpha', 0.5, 'EdgeColor', 'none', 'FaceColor', 'r');

% Draw the inner cylinder
[Xcyl_inner, Ycyl_inner, Zcyl_inner] = cylinder(innerRadius, numPointsX);
Zcyl_inner = Zcyl_inner * height;
surf(Xcyl_inner, Ycyl_inner, Zcyl_inner, 'FaceAlpha', 0.5, 'EdgeColor', 'none', 'FaceColor', 'g');
xlabel('X');
ylabel('Y');
zlabel('Z');
title('Control Net of Cylinder with Inner Cylinder');
axis equal;

Output:

You can read more about the "plot3" function here: https://www.mathworks.com/help/matlab/ref/plot3.html

Hope this helps!