[FLASH-USERS] getting neighbor blocks and blocks on the corners for a given block

[John ZuHone]

Hi folks,

I want to design an algorithm where I can pick a point in the domain based on a particle position, and find all of the particles within a given radius, where this radius is roughly a factor of a few times the local cell size. Based off a suggestion from Paul Ricker, my plan is to query only the particles within the block containing my particle and its surrounding blocks. This would mean I would need to query not only the neighbor blocks, but also the blocks which are on the “corners” of my block. 

Does anyone have any suggestions as to the best way to get this information, assuming a PARAMESH simulation? Getting the processor ID and block ID of neighbors is straightforward, but what about the blocks on the corners?

Best,

John Z