[vtk-developers] OpenGL, picking, fixed-function pipeline, deprecation

David Gobbi david.gobbi at gmail.com
Tue Jul 5 16:26:19 EDT 2011


Hi Sean,

This is just my opinion, but it is best to use the vtkCellPicker for picking
- it is implemented 100% on the CPU and does not utilize OpenGL whatsoever
(and for big, complex geometry it can be accelerated with a vtkCellLocator).
 But I realize that isn't quite what you were asking, hopefully someone who
is familiar with VTK's hardware-accelerated pickers will chime in re: the
OpenGL code.

 - David


On Tue, Jul 5, 2011 at 2:10 PM, Sean McBride <sean at rogue-research.com>wrote:

> Hi all,
>
> I (and my coworkers) know next to nothing about OpenGL (part of why we use
> VTK-- as an abstraction), but here goes anyway... :)
>
> VTK seems to do picking by using the 'fixed-function pipeline',
> specifically by doing:
>
> glRenderMode(GL_SELECT);
>
> then:
>
> GLuint hits = glRenderMode(GL_RENDER);
>
> My understanding is that this technique is deprecated (assuming I've not
> been misinformed).
>
> So, what would be the correct way to re-implement VTK's picking?
>
> (I ask because the current technique is problematic in a certain beta OS,
> which is under NDA for a couple more weeks.)
>
> Someone suggested to me a 'color coding' technique like this:
> <http://www.lighthouse3d.com/opengl/picking/index.php3?color1>
>
> But I don't know if that's appropriate.
>
> Thanks for any pointers,
>
> --
> ____________________________________________________________
> Sean McBride, B. Eng                 sean at rogue-research.com
> Rogue Research                        www.rogue-research.com
> Mac Software Developer              Montréal, Québec, Canada
>
>
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Follow this link to subscribe/unsubscribe:
> http://www.vtk.org/mailman/listinfo/vtk-developers
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtk-developers/attachments/20110705/efb97be7/attachment.html>


More information about the vtk-developers mailing list