[MOAB-dev] Strategies for fixing 2nd adjacency calls in iMesh

[Tim Tautges]

Can you review what the problem is, i.e. what the test is expecting vs. what MOAB's giving it?  It seems to me that the 
results of the 2nd adjacency call should be consistent with the diagonal entries in getAdjTable, which is a fancy way of 
saying that if internal edges/faces aren't represented, don't expect to get the target dimension entities through those 
bridge entities.

- tim

On 03/21/2011 06:13 PM, James Porter wrote:
> Since we have a few more days until ITAPS 1.2 is released, I wanted to see if I could fix the 2nd adjacency issues
> with the unit tests. One way to do this would be as follows: if source_dim<  bridge_dim<  target_dim or source_dim>
> bridge_dim>  target_dim, implement the 2nd adjacency in terms of a single adjacency call (otherwise, use two
> adjacency calls). It seems like it'd be reasonable to do this at the source, in MeshTopoUtil.cpp.
>
> However, this actually causes *more* failures on the ITAPS unit tests because if either the bridge_dim or target_dim
> is iBase_ALL_TYPES, it expects the 2nd adjacency to be equivalent to two first adjacency calls. This is a problem for
> us, since the elements of the bridge dimension may not be explicitly represented. If people (notably Tim and/or
> Jason) think that my first paragraph is the way to go, then we should file a bug to fix this in the unit tests so
> that they use a single first adjacency call when appropriate, even when iBase_ALL_TYPES is specified.
>
> Another option is to change the unit tests to say that a second adjacency call is ALWAYS equivalent to two first
> adjacency calls and get rid of the short-circuiting that it currently does.
>
> The only other option I can think of to make this work is to create explicit versions of any implicit adjacent
> entities when getAdj is called. I'm not sure we want to do that, though.
>
> - Jim
>

-- 
================================================================
"You will keep in perfect peace him whose mind is
   steadfast, because he trusts in you."               Isaiah 26:3

              Tim Tautges            Argonne National Laboratory
          (tautges at mcs.anl.gov)      (telecommuting from UW-Madison)
          phone: (608) 263-8485      1500 Engineering Dr.
            fax: (608) 263-4499      Madison, WI 53706