* Parallelization:
Support for Multiblock datasets and MPI parallel usage. Three compositing
strategies are provided, with a heuristic to automatically make a reasonable
selection between them. [1] INPLACE, [2] INPLACE_DISJOINT, [3] BALANCED.
The inplace strategy processes data where it falls given its parallel domain
decomposition and projection to the screen. For simple surfaces such as
slices where ranks/blocks data does not overlap in screen space this is the
most efficient approach. However where ranks/blocks data have large amount
of screen space overlap, this approach has high communication/compositing
and overhead and a large amount of redundant computation that's discarded.
The inplace-disjoint strategy was designed to address these issues. It
leaves data inplace as much as possible but will assign pixels to ranks
uniquely eliminating redundant computation. The communication costs are
the same as the inplace strategy however they are split into...