Re: [Libmesh-devel] Affine maps

[Derek G. <fri...@gm...>]

On Fri, Mar 27, 2009 at 7:22 AM, Roy Stogner <roy...@ic...>wrote:

>
> On Fri, 27 Mar 2009, Kirk, Benjamin (JSC-EG311) wrote:
>
> > What do you think about adding some bitfields (or bitsets) to Elem
> > to track things like has_affine_map, on_processor_boundary,
> > on_material_interface, etc...?
> >
> > The has_affine_map seems like a big payoff to avoid repeating the
> > flops to determine it...
>
> Maybe I'm wrong; I'll forward this on to libmesh-devel for third
> opinions.  Or maybe I'm just being myopic.  Derek tells me there's INL
> people interested in doing Cahn-Hilliard stuff in his framework, who
> would be using affine grids, and who are referencing my CH talks.
> Speeding that up might help move that along, and I would enjoy
> describing my applications work as "cited in the nuclear engineering
> literature" rather than just "cited by a couple others from my
> department"...



Honestly... this sounds like a pretty good optimization to me.  This
shouldn't be the default behavior though... like Roy says... there are too
many operations that will silently invalidate that bitfield.  If we make it
something you have to turn on manually then you should know that you need to
manually call some other function ( rebuild_bitfields() ?) when you change
the mesh.

This would definitely benefit the CH work I have coming up....

Derek