Body temperature

Body temperature follows these guidelines :

Assumption 1 : a naked person is comfortable at 19C/66.2F (31C/87.8F at rest).
Assumption 2 : a "lightly clothed" person is comfortable at 13C/55.4F (25C/77F at rest).
Assumption 3 : the player is always running, thus generating more heat.
Assumption 4 : frostbite cannot happen above 0C temperature.*

• In the current model, a naked person can get frostbite at 1C. This isn't true, but it's a compromise with using nice whole numbers.

Here is a list of warmth values and the corresponding temperatures in which the player is comfortable, and in which the player is very cold.

Warmth  Temperature (Comfortable)    Temperature (Very cold)    Notes
 
  0       19C /  66.2F               -11C /  12.2F               * Naked
 10       13C /  55.4F               -17C /   1.4F               * Lightly clothed
 20        7C /  44.6F               -23C /  -9.4F
 30        1C /  33.8F               -29C / -20.2F
 40       -5C /  23.0F               -35C / -31.0F
 50      -11C /  12.2F               -41C / -41.8F
 60      -17C /   1.4F               -47C / -52.6F
 70      -23C /  -9.4F               -53C / -63.4F
 80      -29C / -20.2F               -59C / -74.2F
 90      -35C / -31.0F               -65C / -85.0F
100      -41C / -41.8F               -71C / -95.8F

Here are a list of things that affect body temperature :

Big ones : ambient temperature, clothing warmth. Clothing warmth is then reduced by body wetness. Finally, your location for sleeping also affects body temperature. Sleeping in a bed is great, sleeping on the floor is terrible.

Smaller ones that accumulate : fatigue, hunger, sunny weather, clear weather. Also, temperature is shared slightly between body parts. The flu and the common cold also affect a little. Mutations and bionics should, for the most part, affect body temperature as described.

Other notes : fire/lava increases warmth and fights frostbite, but get too close and your skin will blister.