Fixed my issue (a while ago, now remembering others may want to know the solution), the indexing scheme I was using to map the clicked object back into my data structure was flawed. Basically, on all clicks after the first click i had to subtract an index by 1. <br>
<br><div class="gmail_quote">On Thu, Sep 20, 2012 at 4:38 PM, David Gobbi <span dir="ltr"><<a href="mailto:david.gobbi@gmail.com" target="_blank">david.gobbi@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi Robert,<br>
<br>
The cell picker always chooses the object that is parametrically<br>
closest to, and that generally means that 3D cells will be picked<br>
before 2D cells, and 2D cells will be picked before lines, etc. There<br>
is no simple fix without re-writing the picker code so that it<br>
prioritizes cells by dimensionality, i.e. points first, then lines,<br>
then faces, then 3D cells. Likewise the picker could also be made to<br>
prioritize small (or thin) objects over larger objects, to allow e.g.<br>
a small pixel-sized facet to be picked even if it is surrounded by<br>
much larger facets. Do you have any desire to look into<br>
vtkCellPicker.cxx to see what would have to be done?<br>
<span class="HOEnZb"><font color="#888888"><br>
- David<br>
</font></span><div class="HOEnZb"><div class="h5"><br>
<br>
On Thu, Sep 20, 2012 at 1:49 PM, Robert Dean <<a href="mailto:bob.dean@gmail.com">bob.dean@gmail.com</a>> wrote:<br>
> Hello,<br>
><br>
> I have two styles of actors in my scene. the first is a height map using 0.1<br>
> m square cells representing the world seen by a robot sensor. On top of this<br>
> I place planes representing detected walls. Both the grid cells and walls<br>
> are drawn using triangle strips. So the wall consists of a plane made up of<br>
> 4 points.<br>
><br>
> With vtkCellPicker I can pick the cells in the height map with no<br>
> difficultly. But I can only select a subset of the walls. I think the cause<br>
> is that the walls are planes, and therefore too skinny for the picker to<br>
> pick. I tried changing the picker tolerance, but it actually made the<br>
> problem worse.<br>
><br>
> Does this logic make sense? I am tempted to render the walls as skinny boxes<br>
> to see if it makes a difference.<br>
><br>
> -Bob<br>
</div></div></blockquote></div><br>