Proposal for telling an implementation what adjacency info an app/service needs

[Tim Tautges]

Hmm, I'm not sure I like this.  I thought setAdjTable was supposed to be used to request which entities an application 
or service needed.  I've coded it into MOAB's iMesh implementation that way, IIRC.  Looking at the current comments to 
getAdjTable, we should put something there describing what the values mean then.  I would vote for setAdjTable being the 
function used to request intermediate-dimension entities.

- tim

Jason Kraftcheck wrote:
>
> I don't think this is the correct way to do this.  The getAdjTable 
> function returns the cost of making such queries.  It doesn't say 
> anything about whether not, for a database such as MOAB that uses a 
> reduced representation, that the requested entities are guaranteed to 
> exist.  I assume that with your setAdjTable command you are trying to 
> require that the database guarantee that lower-dimension entities exist 
> explicitly that correspond to sides of higher-dimension entities. 
> Otherwise I'm not sure what it means to set the adjacency table.
> 
> If my assumption is right, then the functionality you are requesting is 
> not analogous to the getAdjTable function.  For example, with a reduced 
> mesh database it is common for meshing applications to define the quads 
> corresponding to sides of hexahedra only on the skin of a hex mesh.  The 
> getAdjTable results give some indication of how quickly the database can 
> find whether or not such quads exist for a given hex and return the ones 
> that due.  It says nothing about whether or not you'll get six quads for 
> a given hex.
> 
> - jason
> 

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              Tim Tautges            Argonne National Laboratory
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