Plotting a sphere consisting of planes

Hi folks,

i want to plot a sphere consisting of triangular planes. The cartesian coordinates of the planes are given by their respective corner points A, B and C which have their own 3D-coordinates A(Ax, Ay, Az), B(Bx, By, Bz) and C(Cx, Cy, Cz). The usual plot-Function does not produce reasonable results.

Does anyone has a suggestion?

[darova]

Can you show some of your attempts? Do you have a picture of the result? Can you make a simple drawing or something?

[Paul]

The plotted result should be similar to the picture from the description of the icosphere-function in the MathWorks File Exchange (see attachement).

My attempt:

A = surfacessphere;          %coordinates of the triangular faces are stored in the surfaces_sphere.txt

Ax = A(:,5);                 %
Ay = A(:,6);                 %Defining columns of Matrix A as columnvectors
Az = A(:,7);                 %

Bx = A(:,8);                 %
By = A(:,9);                 %Defining columns of Matrix A as columnvectors
Bz = A(:,10);                %

Cx = A(:,11);                %
Cy = A(:,12);                %Defining columns of MAtrix A as columnvectors
Cz = A(:,13);                %

plot3(Ax,Bx,Cx);             %
plot3(Ay,By,Cy);             %Plotting
plot3(Az,Bz,Cz);             %

Answer 1

[darova]

Use patch for this problem

% create data of format
% Ax Ay Az
% Ax Ay Az
% ...
% Bx By Bz
% Bx By Bz
% ...
% Cx Cy Cz
% Cx Cy Cz
% ...
fv.vertices = reshape(A(:,5:13),[],3);
% create connection list of format
% 1 n+1 2n+1
% 2 n+2 2n+2
% 3 n+3 2n+3
% ...
n = size(A,1);
fv.faces = [1:n; (1:n)+n; (1:n)+2*n]';
fv.facecolor = 'yellow';
patch(fv)

[Paul]

Thank you, your answer helped a lot!

I was trying to apply these functions to the geometry of a cylinder also consisting of triangular planes. The result should be displayed in the xz-plane and look like the plot in the attachement.

The coordinates of the planes are given by their vertices: A(Ax,Ay,Az), B(Bx, By, Bz) and C(Cx, Cy, Cz) for one triangular plane.

I've attached the textfile in which the coordinates are stored.

How can I change the previous script in order to get a result as in the picture in the attachement?

[darova]

Everything is the same. Why shouldn't it be different? The script i wrote i just plot triangles, it doesn't know what shape is. Are you asking of how to read data?

[Paul]

Unfortunately the result of the submitted script looks like the attacheted picture and not like the cylinder in the xz-plane (attachement). Reading data is not the problem:) (i think)

[darova]

I made a wrong script, sorry. Try this:

A1 = importdata('surfaces_cylinder.txt');
A = A1.data;
ii = [5 8 11];
patch(A(:,ii)',A(:,ii+1)',A(:,ii+2)','y')
axis vis3d