I started to play with elemental files to see how the game react. The results are sometimes surprising and frustrating.
I first tried making minor modification to terraintypes.xml like changing terrain name, with a few other parameter and nothing works. So I decided to go the agressive way, I deleted the XML file. Nothing happens either. I used a software called "text crawler" that allow searching in the content of multiple files and there are no terrain type definitions elsewhere.
Then I said to myself, I'll try modifying other parameters in case the terrain types have a special treatment. I emptied the city level up bonus entries and I made modification to the number of people required to level up. I started the game, none of these changes applied.
Then I said to myself that maybe reloading a game does not makes the change apply. I would need to start a new game. Still I thought I made the test before but I tried again. Now a new game start up freeze (or loop indefinately). I thought that it might be because I deleted the terraintypes.xml was previously deleted.
So I restored terraintype.xml and modified terrain name "submerged" for "water" to see if he actually pass into the file.
I started a new game again. Now it works. The terrain change name, and there is no options when leveling a city up but the min population required to change a city level(that I changed) had no effect. It still use the default values.
So in general, it seems that something is saved in the save game which overrides any modification to the XML. I thought that maybe each save game has a binary blob of it's own? Else, how could a game run if some xml files are deleted. Where does it gets it's information?
Does any people have experienced the same kind of problem?
I just find it annoying for mod play testing that I would need to start a new game all the time to make sure the new parameters applies. I know there are cheat codes, but sometimes, you want to test something fast and starting a new game all the time is not the way to do it.