Fast Downward 22.12 released

[Malte Helmert]

[now with the correct subject -- sorry for the duplicate messages!]

Dear Fast Downward group,

we are happy to announce the release of Fast Downward 22.12.


Highlights:

- We now test more recent versions of Ubuntu Linux (22.04 and 20.04),
macOS (11 and 12) and Python (3.8 and 3.10).

- Most search algorithms are now faster. We fixed a performance problem
related to state pruning, which also affected search configurations that
did not explicitly select a pruning method.

- All landmark factories now respect action costs. Previously, this was
only the case when using admissible landmark heuristic or when using the
lm_rhw landmark factory. Note that ignoring action costs (i.e., the old
behaviour for landmark factories other than lm_rhw) often finds plans
faster and is still possible with the adapt_costs transformation.


The Apptainer (formerly known as Singularity) and Docker distributions
of the planner include LP support using the SoPlex solver. Thank you to
ZIB for their solver and for giving permission to include it in the
release. SoPlex is licensed under the ZIB Academic License.


To download the release and to see the full set of changes, see:

https://www.fast-downward.org/Releases/22.12

As always, please let us know if you encounter any problems with the
release artifacts (tarball, Apptainer image, Docker image, Vagrantfile).

Happy planning,
the Fast Downward team