MPFever 0.6.9

We found a big cause of the "resyncs for no reason": players with different DLCs. Also: every company's vehicles now wear, the difficulty applies to towns again, and several desyncs are fixed.

MPFever is still in active development: back up your savegames.

Archives

• MPFever-0.6.9.zip: for players.
• MPFever-0.6.9-server.zip: the dedicated server.

MPFever 0.3.15 and later update themselves to 0.6.9 when the game closes. Every player needs the same version.

The big discovery: every player needs the same DLCs

The Deluxe edition's upgrade pack and the pre-order pack turn themselves on in every game of a player who owns them. They add animals, people, vehicles and landmarks. So if one player has them and another doesn't, the two games don't simulate the same world. Bit by bit, vehicles, lines and towns drift apart, and the game has to reload.

We found it in the reports of several groups who had resyncs "for no reason" (#109). In each of them, one player had the Deluxe and pre-order packs and another had none.

New in 0.6.9: MPFever compares the DLCs of every player.

• If they differ, the lobby shows a red warning, for example "keviK has the Deluxe pack, the host does not: the game will desynchronise".
• The host's player list says "(different DLCs)".
• The problem report now lists each player's DLCs.

If you had resyncs without any reason, check this first.

New

• Every company's vehicles wear now (one company per player). Until now, only the host's savegame company paid for wear. The other players' buses, trucks, trains, ships and planes stayed at 100 % for years and never needed a depot. Now every vehicle wears and gets repaired at depots, the same way on every game.
  • In an existing save, the other players' old vehicles will start to wear after the update. Plan for depots near your lines.
• The difficulty applies to towns again. MPFever used to turn off how towns react to pollution, noise and traffic, to keep the games in sync. So on "Very hard", towns never minded fog or noise. That safety is no longer needed: towns react as the difficulty says, old saves included.
  • In an existing save, towns next to busy lines or industries may now grow slower.

Desync fixes

• Builds that landed late: a game waited 12 to 30 s at most (depending on the screen's frame rate) for a build announced by another player. If that player's game was busy, the build arrived later and was applied a few steps late on the others, which led to a desync. A game now waits at least 60 s.
• Computer companies' stops on tree-lined streets: the street lost its trees on the host's game only. That was a desync every time.
• Computer companies' stops next to traffic lights: the lights' timing was kept on the host's game but not on the others, so the traffic, then the towns and vehicles, drifted apart a few minutes later. Every game now gets the same timing.
• Computer companies' railways: planning a long railway froze the host's game for up to 17 s, every player waiting. A plan now takes 2 s at most.

Computer companies (still experimental)

• They no longer give up a pair of towns for good: they try again two years later. Before, they often stopped building after a few minutes.
• They borrow only what they need. One of them took 59 million for 95,000 missing.
• They now use the streets next to traffic lights for their stops, without the engine error that used to stop the game.
• They no longer put a garage next to a junction with traffic lights.
• In a 30-minute test with 3 computer companies, they opened 13 lines (0 with 0.6.8).

What our tests showed

• The long test with one company per player passed with no desync and no crash: two players building at the same time (roads, stops, street upgrades, another company's street, station edits, industry extensions, purchases), a resync, then 5 minutes at x4 with 2 computer companies. The same test failed with 0.6.8.
• The free-id differences behind #109 do not come from the build tools' previews, nor from the computer companies' trial builds: we tested both. What remains comes from differences between two PCs, such as the DLCs above.
• If you still get resyncs after checking your DLCs:
  1. Every player creates an empty file named diag.txt next to MPFever.exe.
  2. Play as usual.
  3. Send us the reports of every player from the same moment.

Thanks

• AMD and keviK: their logs from both sides of the same session revealed the DLC problem.
• DubstepDude-hub, Kev1505in and hschi: the reports of #109 that showed the same thing.
• DrWolf03 (#119), kasa1990 (#120) and Acki007 (#117) for their reports.
• The Discord members who noticed that the difficulty did nothing on towns and that other players' vehicles never wore.

Our Discord: https://discord.gg/DfMxFUQZCR

If you enjoy MPFever, you can support it on Ko-fi.

Files:

• MPFever-0.6.9.zip, SHA-256 BEFAAF731397249590416140B38F30BFCE9307FBDCA641810104A1983B0F625E
• MPFever-0.6.9-server.zip, SHA-256 940267FCFF6C52ACD7B7BA99FB9EE68655BF477E99AC195E4A0BBBA545DBBACD