[pdal-commits] [PDAL/PDAL] f7fbbd: Accelerate morphological operations

[GitHub]

  Branch: refs/heads/faster-morphology
  Home:   https://github.com/PDAL/PDAL
  Commit: f7fbbdc9e7de5fba4919310e8b133a0b4e394863
      https://github.com/PDAL/PDAL/commit/f7fbbdc9e7de5fba4919310e8b133a0b4e394863
  Author: Bradley J Chambers <brad.chambers at gmail.com>
  Date:   2017-03-24 (Fri, 24 Mar 2017)

  Changed paths:
    M filters/PMFFilter.cpp
    M filters/PMFFilter.hpp
    M filters/SMRFilter.cpp
    M filters/SMRFilter.hpp
    M pdal/EigenUtils.cpp
    M pdal/EigenUtils.hpp
    M test/unit/EigenTest.cpp

  Log Message:
  -----------
  Accelerate morphological operations

filters.pmf and filters.smrf both spend a majority of their time in the
morphological operations (erosion and dilation). As it turns out, we don't gain
much by using Eigen to implement these either. By storing our matrices as
vectors in column-major order, and refactoring the erosion and dilation
functions slightly, we have achieved speedups of greater than 2x for both
filters.

We also had a bug in SMRF, as the erosion and dilation steps were reversed in
the net cutting procedure.

Finally, we have added some additional tests for both erosion and dilation.