Hi Eitan,

Here is the story. I have a need of Incremental heuristic search in Base
Global Planner for long range navigation in an unknown area, so I tried to
modify your A* in move_base to D*
Lite<http://idm-lab.org/bib/abstracts/papers/aaai02b.pdf>.
However, it is really difficult to arrange the order of the re-explored
cells in the priority buffer because you are using the threshold curT to
control the behavior of the priority queue. And also, some re-explored cells
have to be updated twice by the D* Lite during the re-planning. So I take
use of your code to realize a new way: 1) Keep the potarr during one long
range move; 2) Swap the start and goal cells before the propagation, make
your A* as a backward version; 3)Do a limited re-propagation when
re-planning is necessary. I also create a PointCloud2 message for the
explored potential area, and add this patch
<https://code.ros.org/trac/ros-pkg/ticket/4610>to visualize the message.
Here <http://www.youtube.com/watch?v=jTt4IrsOqEU> is a screencast of my
experiment.

At the moment, this method is not stable yet, some times the robot will be
stopped by the incomplete potential area. Do you think it is a good way to
do the Incremental replanning? Or it is still possible to realize the D*
Lite based on your A*？

Cheers,
Simon