raduprv/Eternal-Lands — comment on commit 44e088623ed44711aa3f67e0fe2dad471d4ae6d0
File:  line 0
By gvissers:

>Well, technically, the Manhattan heuristic used does not guarantee an optimal path

Expanding on that, consider going from a to b in the following grid (. is walkable, * is occupied):

...b
.*..
.*..
a...

The old heuristic gives this path:

.ooo
o*..
o*..
o...

and the new heuristic results in this path (which is shorter)

...o
.*o.
.*o.
oo..