I thought it would be more appropriate to reply to
this post in this thread.
Ammler wrote:we should really think about save compatibility to CIV Build2, So something like a table which patch adds settings, which one changes map format, so we see easy which patches should be included to have a save compatibilty.
Generally I like save game compatibility, but I wonder about how difficult something like that would become. There is the problem of what to do with a setting for a patch that was in the prior build, but wasn't submitted for the current build. Someone has to write code to deal with the extra data in the save file. Ok, maybe thats not too hard, but its extra work for someone. If it is a patch like YAPP, what happens to all the Path based signals on the map?
I feel that trying to do save game compatibility would make us look like we are trying to compete with the trunk, and distract from what I feel is the main goal of CIV. It also feels contrary to the resubmit each build rule. If a patch is not resubmitted, but put data in a save file in an earlier build, we would forever be dealing with that patch in future builds. These are the kind of issues that have to be addressed when adding a patch to the trunk. Basically once you add something to a code base, and even if you decide to remove it later, there may be fallout from that decision forever.
I also feel like the reason for dropping the CIV code base every so often and starting fresh is just so that this kind of cruft can be avoided. Save game compatibility would mean that each release would become progressively more difficult as more and more code would have to be customized to deal with long gone or obsolete patches.
To be blunt, I don't think save game compatibility is worth it, and I won't be writing the code to do it.
I'm not against there being a Wiki page, but I am weary of promising something that would create more work. I'm happy if someone else wants to do it, but I worry that without regular work it become stale. My other concern is that I feel that the Wiki is a little more official than this project. I don't want the core developers to feel like we are impinging on there territory. Honestly I'd rather wait for an invitation to use project resources like the wiki and possibly version control. However all this is personal opinion, so don't let that stop you from doing it if you are so inclined.