Meteorites and castle protection

The logic is in Meteorite.<Execute>d__4.MoveNext (state 0), decompiled from game version 1.0.4. The Meteorite object has these integer fields:

All three are read live for every meteor and are not clamped by the game. A limit such as 1000 in a mod's settings is the mod's own clamp, not the game's.

Choosing the impact tile

1. scorched = IslandGrid.CountGround(grid, 5): the number of scorched earth tiles (ground tile 5).
2. One random roll per meteor: roll is uniform in [0, T), computed as (uint)(random.state * (int)T) >> 32.
3. Up to 256 times: pick a random grass tile, count the castle tiles inside the radius (IslandGrid.MeteoriteNumberCastleTiles, castle tiles with squared distance at most radius^2), and accept the pick if castleTiles <= 0, or if scorched > roll and castleTiles >= minimumCastleTiles.
4. If all 256 picks were rejected, the last pick is used anyway.

Consequences

• The castle can be hit with a probability of min(1, scorched / T).
• T = 0 protects the castle only while there are no scorched tiles (protection for the first meteor).
• A huge T (up to int.MaxValue) makes a hit on the castle practically impossible.

What the impact does

IslandGrid.MeteoriteDisaster: for tiles within the radius that are inside the island limit (HardLimit.IsWithin): skip ground tile 1; remove inner cliffs if the ground is 4; set the ground to 5 (scorched earth); apply the disaster to or remove the buildings there; add the nature object 3 (lava).