[vtkusers] How to determine wether a given point is visible or not?

[Jonathan Bailleul]

Dear all,

I am looking for a way to visualize a 3d shape whose vertices would be
annotated by their respective number in the vtk file. The way I
implemented this feature consisted in retrieving the 3d world
coordinates of every point, then their 2d projections, and to finally
display 2d actors labels at every location when a key is pressed.

There are 2 major drawbacks of this approach:
- labels do not move with the object actor: they are not glyphs. But
that's ok anyway.
- I get the labels of points from the other side of the object, wich
tends to make the display hard to read.


To overcome the latter drawback, is there a way to determine wether a
given point is visible or not?
I've looked over the documentation without result until now...

Thanks in advance!


-- 
-----------------------------------
Jonathan BAILLEUL, Doctorant
GREYC Image - Université de Caen 
http://www.greyc.ismra.fr/~bailleul