Upgrading an old map to Minecraft 1.7
Terrain Control always tried to make sure old configs still produce similar terrain on modern versions of Terrain Control. Trees would generate on a different spot, but there wouldn't be an ugly border between old and new terrain.
For Minecraft 1.7 we have tried to do the same, and we've been quite successful: terrain shape and biome layout are still the same. However, you'll most likely need to do a few changes to your world. Before you upgrade to Minecraft 1.7, please do the following steps.
It goes without saying, but make a backup of your whole server: world, plugins, configs, everything that you don't want to lose. If anything goes wrong, you'll be very happy that you made a backup.
Mojang has doubled the amount of vanilla biomes, so if you're using custom biomes, most likely at least some of them will need a new id. Go to the WorldConfig file and change the ids in the CustomBiomes setting.
The old taiga biome no longer has snow, except on some mountain peaks. Set the ReplaceToBiomeName setting of both Taiga and TaigaHills to Cold Taiga if you still want snow for newly generated taigas. To fix all existing taiga biomes in your world, use one of the biome id replacement tools mentioned above to change all occurences of the ids 5 (Taiga) and 19 (TaigaHills) to 30 (Cold Taiga).
Have a biome with a low temperature like 0.2? Previuusly, that was still high enough to prevent snow. However, in Minecraft 1.7 the biome will now have snow on the top. The height at which it starts snowing is calculated like this:
snowHeight = 600 * biomeTemperature - 30
Or, if you want to know what biome temperature you need for a given snow height:
biomeTemperature = snowHeight/600 + 0.05
So if you don't want snow at all you'll need to increase the biome temperature. 0.48 is enough to prevent all snow, even if a player builds to y = 255.
