[vtkusers] Perspective view of vtkCursor3D

[Granseier, Michael (VISUS)]

Hello all,

I have already solved the problem.
The objects do get smaller when they are further away from the camera.
I just haven't noticed it in the volumes I observed.
Using a ruler on the screen shows a small reduction in size.

Sorry for my rash and unnecessary post. ;)

Michael



-----Ursprüngliche Nachricht-----
Von: Granseier, Michael (VISUS) 
Gesendet: Montag, 13. September 2010 16:35
An: 'vtkusers at vtk.org'
Betreff: Perspective view of vtkCursor3D

Dear VTK Users,

I'm trying to mark a three-dimensional point in a volume using the vtkCursor3D class.
My problem is, that the length of the crosshairs' lines stay constant, even if the position of the point is farther away from the camera.
I'm using SetModelBounds to specify the length.

The same problem occurs with a vtkSphereSource. The radius of the source stays the same, no matter how far away it is from the camera.

Is it possible to scale the crosshairs' lines or the sphere radius relative to the camera distance?
So, that the marker-object becomes smaller, the further the specified point is away from the camera and larger, the closer it is?


Thanks for any kind of help.

Michael