Change internal temperature scale from relative to absolute

[geostar1024]

TL;DR

An absolute temperature scale (e.g. Kelvin) should be used internally rather than the current relative temperature scale to allow for entities to have temperatures below 0C.

What ?

Essentially, this is a proposal to shift the zero point of the temperature scale, so that 0C becomes 273K internally (though temperatures probably should continue being displayed in Celsius). As far as I can tell, this should not have any noticeable effect on current vanilla gameplay as only relative temperature differences are important.

Why ?

The primary benefit of this change would be to enable the use of processes that require sub-freezing temperatures. For instance, one could envision needing to keep heat-producing entities at cold/cryogenic temperatures in order for them to continue functioning (for example, the supercomputers in the Space Exploration mod (currently handled in a bit of a roundabout manner)).

[Klonan]

Temperature can already be negative, its a floating point number

[geostar1024]

Ah, good to know. Well, the reason this came up was that I was trying to set the temperature of a reactor to less than zero, but it won't go below 15C (which I had assumed might be to do with the way temperature was represented internally). So, then, it looks like there's some kind of artificial temperature floor for entities right now?

[geostar1024]

I have been informed that I need to read the documentation more carefully (it looks I need to be setting default_temperature on an entity).