[vtkusers] Create polyData from 4 points

[Francesco Ferro]

Hi all,

I would like to know if is it possible to create a polydata from 4 
points ? here an example of what I'm trying to do.

1. I have a windows where I can display 3D object and where I can draw 
with the mouse on a 2 overlay (using Actor2D and polyMapper2D...)

2. I click on my windows 4 times that will create 4 points on my windows 
(imagine I click the 4 edges of a square for example....)

3. I'd like then  draw lines between there 4 pointes (so it will display 
like a 2d square...)

2. And then I'd like from these 4 points create a 3D object. with the X 
and Y dimension I clicked and an "infinite" or very longue dimension in Z.

Is there any easy way or Intelligent way to do that ? Storing the points 
in a particular data or array ?

Thank's in advance