Topic: I've discovered a cheater

the-x cheated in some matches during the last days. He manipulated files so he gets a decent bonus of gold, iron and coal after 5 minutes (the match desyncs then and has to be reloaded).

Here are two replays which prove it.

Wanted to save the world, then I got widetracked

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Well, from a neutral point the replays show a significant increase of wares for frisians (the-x) after around 5 to 6 minutes. and it crashes exactly when iron in HQ reaches 0. So far this supports WorldSavior's claim.
At least the game which I watched until the end was won by WorldSavior regardless. This somehow is not supporting the theory of revenge for a lost game.
Just neutral observations. May everybody make his own mind about this.

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@the-x: Maybe WorldSavior can't accept loosing a game, but you didn't argue against the facts hessenfarmer postet.

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We had something like this before when we played on Wisente Valley. In this game the exact same thing happend, vice versa. World Savior played Barbarian and was given around +35 Coal, Iron and some gold which I didnt know. I was only given 10 Iron and Coal by his starting conditions. I was playing a honest game and did not know this till I watched the replay. Probably it had some thing to do with trading post start, but world savior called this one a competitive 1v1

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I do not really understand what is going on here from an interpersonal level, however I feel I can add to the technicalities and at least add an explanation the last question:

What I understand from this rather unpleasant discussion is that there is the possibility for players with programming skills to change the amount of resources stocks during the game...

This statement is not correct. Let me explain: Widelands works on the concept of parallel execution verified by hashing, i.e. all computers in networked games have all the information at any point in time. All computers drive the simulation forward independently and they exchange hashes of the current game state with each other. So all calculations on all machines must be exactly equal, otherwise the hashes become different. These hashes must be the same at all points, otherwise the computers have different opinions of the current game state, i.e. the game has desynced.

This means you generally cannot cheat by scripting, i.e. by executing some code by typing for example in the debug console or changing a script only on your computer: the scripts are not shared over the network, i.e. they only execute on one machine and hence their effects only affect the game state on this one machine. If the things you changed (for example adding wares to your warehouse) ever affect the state of the game the network game will desync. The only meaningful cheat I can think of is to give you full vision, i.e. uncover the map: This will not affect the game state (unless you are using scouts and I think ships, which base decisions on the players visibility).

Similarly, if one player alters starting conditions while the other does not, the game will desync (since the changed starting conditions will execute only on one machine). Same argument if map scripts are altered, the game should descync unless the modified map is shared with all players.

So to summarize: To cheat in a game, you would need to either alter the scripts on both machines (maybe by changing the code in a branch and get the other player to play this branch) or you'd need to alter the map on both machines, for example by sending a modified map around and make sure everybody is using exactly this version - otherwise you will see a desync in the game. As a disclaimer: most desyncs are just bugs and not somebody trying to cheat of course.

Looking at the attached data in this thread, the save files claim to be generated by Widelands b21 Release (though that could have been falsified and scripting files could have been altered in the released version) and the maps in the savegames do not contain any .lua files. This indicates that the map was not modified on both machines, but could have been on the machine that this savegame was not on. What remains as potential explanations is that a player changed the starting conditions on their computer, but not on the other players computer - and this should lead to desyncs as soon as state-altering logic is executed on one machine. Resyncing happens through loading one of the savegames - either from computer 1 (no script executed, i.e. no added wares) or from computer 2 (with added wares) and in fact modified game state could be shared that way. The game can then be continued on, since the states have been resynced.

I will not judge if what happened here was cheating or testing, malicious or in good nature, but generally speaking a player with programming skills cannot cheat without it leading to desyncs. If testing of new starting conditions was the aim here, care should be taken that both sides execute the same scripts, otherwise the game will always desync.

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