[vtkusers] Clipping planes

[James C. Robinson]

Dear All,

I have written an application to view finite element results. The mesh can
be of the order of 2000m in width/depth but may be only 10-30m thick. It
also may have an important feature with a dimension of the order of less
than 1m to view. My problem is that when I zoom in (using a vtkCamera) the
near clipping plane is too far from the camera and part of the mesh is cut
(clipped) away. I have tried resetting both the near & far values (using
SetClippingRange & SetThickness) but to no avail.

I have noticed that, if I set the majority of the mesh to be invisible, but
leave an object of the small dimension required, the zooming works fine. I
can then set the overall mesh to be visible and the image looks fine.
However, as soon as I move the camera position, a lot of the mesh is again
clipped away. What is happening is that the clipping range is set to values
(automatically) that are suitable to zoom in on the small object when it is
on its own, but are reset to unsuitable values a soon as the whole (larger)
object (mesh) is visible.

Has anybody any suggestion?

Regards,

Jim
______________________

James C. Robinson, PhD,
Chartered Engineer,
Kepler Engineering Software Ltd.,
42 Rivergrove,
Glanmire, Co. Cork,
Eire

Tel:         +353-21-4822028
Tel:         +353-87-2393010
Fax:        +353-21-4822721
E-mail:     j.robinson at kepler.ie
______________________