V12.02 Supply Path Tracing Bug

[Shalkai]

Both myself and others have pointed out supply path issues in the current v1.12.02 patch. I am posting again about issues specifically related to the new algorithm which chooses supply path based on least MP cost, not any other factors.

The following should point out a situation so illogical that I can only describe it as a bug - on my Turn 7, Krivoi Rog is in supply, at 31 MP and 23 hexes from railhead. Two nearest railheads are at 72,104 and 68.90.

[Shalkai]

Attached is Turn 7 Axis end of turn save.

[Shalkai]

Next turn, the supply path is recalculated, and Krivoi Rog is isolated, at 26 MP and 26 hexes from a different railhead. I understand why the game engine chose the different path to supply, but it is a rather ridiculous choice. No supply officer would stop sending trucks out on a working route because a different, longer path was available, but it was too long to use.

[Shalkai]

Attached is Turn 8 Axis end of turn save. Nearest railheads on Turn 8 are at 73,105 and then at 71,89 (Vinnitsa).

[Shalkai]

I would like to request that this new supply path along least MP be changed or at least reviewed. Since the major limit to supply distance is hexes, not MPs, in most weather conditions, it would seem more logical to base the supply path primarily or at least partially on hex distance.

Suggestions:
1. Change supply path choice algorithm to choose path based on SUM(Distance+MP Cost). A complex change, but should give good results in all weather conditions.
2. Add ‘avoid isolation’ check to current MP path choice i.e. if path chosen is >25 hexes, look for alternate path of 25 or less hexes.
3. Change supply path choice algorithm to choose path based on Distance; then in case of ties then it chooses least MP cost.

Any of these options would improve things, and there might be even better ways to update the algorithm. Hopefully something can be done without requiring very much added code.

[Shalkai]

Every turn I am seeing supply paths taking extended routes which cause a hex to be at 26+ hexes from rail, while an adjacent hex uses a path which is 20 or less hexes from rail.

Below is another example that can be verified in the Turn 8 save. Hex 91, 40 is isolated, at 31 MP and 26 hexes. The 90,40 hex adjacent to the west (with the 7-1 division) is at 31 MP but only 18 hexes from railhead.