As requested, here are some details on what is actually causing crashes. This may be somewhat technical.As you may be aware, in the past EF had problems with recrewing weapons. This is because CoH is hardcoded to only read capture squads for the 4 basic factions from team weapon entities. If you try to capture a team weapon with a Soviet squad, the game will crash because it cannot find the appropriate entry in the RGD (and subsequently runs into invalid memory sooner or later).What I did back then was writing a custom DLL FactionFix.dll which for all purposes acts like the original game DLL (WW2Mod.dll; in fact it just forwards any calls to that DLL) but does some in memory patching, i.e. it changes some parts of the code in the original DLL. The code that is changed is the code that controls which squads are spawned when a team weapon is picked up. Whenever a non-standard faction tries to pick up such a weapon, my code jumps in and calls a certain ScaR function that returns the RGD-path of the appropriate squad. (To get the actual Lua-state of the ScaR-instance, I make use of Corsix' LuaExtCore.dll.).Everytime a patch containing more than just balance changes is released, there is a chance that the address of the code that is to be patched has been changed. If parts of the DLL have been recompiled, it is even possible that parts of the fix have to be rewritten: Because we only have the binary files (i.e. the compiled code), my code needs to seamlessly interface with x86 assembler (which I very much like). Unfortunately that means, that if the compiler thinks it is better to put some value that was in some register EAX last time around into EBX this time, I have to rewrite parts of the code and spend sometime reverse engineering the data flow. These are all things that can be done rather quickly (even if some engineer at Relic decides that what has been an __stdcall up to v2.601 should be a __thiscall in 2.700).The ugly part is if things do not work out immediately: This stuff is impossible to debug; without proper debug symbols even the stack traces of DMP-files are bogus and most applications totally don't like being debugged. Furthermore, debugging without any source code is tedious and not fruitful (especially when you are working with a system where you do not even have the faintest idea what most of the functions actually do!).So what I currently have is the following:I have updated the DLL accordingly and I have noted that besides some changes in the offsets, WW2Mod.dll has not been changed in the parts relevant to this patch. Still, the patch is not working as intended: Sometimes it works, sometimes it crashes, and sometimes it does not even allow a weapon to be recrewed (the cursor does not change into the right symbol and no action is possible). This (in a way) is the worst case scenario: My code seems fine (it is the same as for the last version and it worked for that one), but the behavior is somewhat non-deterministic. Sometimes you can capture a weapon, yet other times it won't work (using the same squad type and weapon type). If the game was crashing consistently, I could just look at where it is crashing and backtrace from there. But it does not.I am not sure what causes this behavior. I have already witnessed similar behavior when I only patched an irrelevant part of the code (swapping two independent opcodes). This could indicate that some kind of memory protection mechanism is employed, yet I am not willing to believe this (why would it show that specific behavior? Why wouldn't it just crash all the time?). Non-determinism in behavior may also be indicative of multiple threads using the same code with non-thread-local data, but I highly doubt that because my testing setup was fairly isolated and it seems unreasonable to distribute the game logic to different threads, at least for this specific case. Another possibility is that I am missing a new piece of code that was inserted, but I was unable to find anything.As you can clearly see, this problem is specific to mods that have additional factions.To clarify another thing: I am not getting paid for this. Nobody here is getting paid for anything. And even if you did, you would not be entitled to anything because quite obviously, you did not pay for anything .
Compatibility fix is for people who play only with the 2.602 version. If you use the new Steam version, you don't need it.
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Topic: Eastern Front Patch 2.2.2.0 (Read 28858 times)
