Question: is it possible that the box generator generates a patch which does not touch physical boundaries but has ghost cells out of physical boundaries?

[humhang]

My application needs special treatment when ghost cells out of the physical boundary are used in calculating the fluxes, and for this reason I need to know whether a patch has ghost cells out of the boundary or not.

I use PatchGeometry::getCodimensionBoundaries(int) to determine if a patch touches the physical boundary and in which direction. However, would it be possible that a patch does not actually touch the physical boundary but has ghost cells out of physical boundary?

For example, the index range of the domain is [0, N], and the patch has index range [1, N-1], but a PatchData has ghost width 2.

[nselliott]

The normal box generation called by GriddingAlgorithm should not produce any patches in that kind of position. The patches should either touch the physical boundary or be far enough away from the boundary to keep all ghosts inside the physical domain.