MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn moreOpportunities for recent engineering grads.

Apply Today**New to MATLAB?**

Asked by Lalit Patil
on 3 Dec 2012

I have This text file..

http://speedy.sh/cMuQJ/data.txt

fileID = fopen('data.txt');

C = textscan(fileID, '%f %f %f');

fclose(fileID);

X=cell2mat(C(:,1));

Y=cell2mat(C(:,2));

Z=cell2mat(C(:,3));

patch(X,Y,Z,'R')

view(3)

axis equal off tight vis3d; camzoom(1.2)

colormap(spring)

rotate3d on

From this code i am creating a 3D of an object, now i want to fill the image surface so that it looks like a real smooth object.

So, how to do it..?

*No products are associated with this question.*

Answer by Walter Roberson
on 3 Dec 2012

I looked at your data, and I think patch() is really giving the wrong idea of it. If you scatter3() it, then you get a fairly different 3D view, more like a 3D T shape whereas patch fills in part of the T angle giving you large triangles defined completely by their edges (with no interior points defined.)

It should be obvious by examining the data and seeing it jump from 752 back to 1 on the X coordinate that using a single patch is not appropriate. Perhaps using one patch per cycle of X coordinates.

The method for creating a smooth surface is going to depend on which representation is correct. Is it like a T with a door-latch type opening on the crossbar, or are those triangles really there even though they have no interior points?

Lalit Patil
on 3 Dec 2012

plot3() and scatter3() both are giving a wrong result to me.. Patch gives satisfactory result..

My object is of this kind..

## 0 Comments