[vtkusers] Setting up a perspective project

[Greg Scott]

Hi there,

I would like to use the perspective projection facilities in VTK. As I
understand it, this is enabled using vtkCamera. I have been looking through
the manual pages, but have not found exactly what I am looking for. If
anyone could help, I would like to know the basic procedures for:

(a) Setting the focal length of the camera, i.e. distance of front view
plane to the focal point
(b) Setting what I would call the aspect ratio of the projection

Any code examples would be appreciated.

Thanks
Greg