Difference between revisions of "v0.34:Temperature"

Revision as of 00:41, 12 June 2012

xTATTEREDx · +FINE+ · *SUPERIOR* · ≡EXCEPTIONAL≡ · ☼MASTERWORK☼

v50.14 · v0.47 · v0.34.11 · v0.31 · v0.28 · v0.23

This article is about an older version of DF.

For temperature as it relates to choosing an embarkation site, see Climate.

Temperature scale

Dwarf Fortress uses its own temperature scale in most cases, often called "Degrees Urist" on this wiki. So if you see something like [HOMEOTHERM:10067], don't be amazed.

Magma's temperature is 12000 °U.

The highest possible temperature in Dwarf Fortress is 60000 °U — the temperature 60001 °U is used internally for temperatures which have been set to "NONE".

Conversion

[DF scale] = [FAHRENHEIT] + 9968

[DF scale] = [CELSIUS] * 9/5 + 10000

[DF scale] = [KELVIN] * 9/5 + 9508.33

[DF scale] = [RANKINE] + 9508.33

(Note: Mod-makers may find this Temperature Conversion Utility handy if they find themselves having to convert a lot of temperatures to and/or from Degrees Urist.)

Reference Chart

Significance	DF Scale	Fahrenheit	Celsius	Kelvin	Rankine
Boiling Point of Water	10180	212	100	373.15	671.67
Human Body Temperature	10066.6²	98.6	37.0	310.15	558.27
Freezing Point of Water	10000	32	0	273.15	491.67
Absolute Zero	9508.33²	-459.67	−273.15	0	0
DF Scale's Zero¹	0	-9968	-5555.555...	-5282.40555...	-9508.33

¹: Yes, temperatures in Dwarf Fortress can go far, far below absolute zero, which is physically impossible. Considering Dwarf Fortress also allows perpetual motion, it's best not to ask questions.

²: Technically, fractional/decimal temperatures are not possible in Dwarf Fortress, as they are stored as unsigned 16-bit integers. For instance, body temp for humans in the raws is rounded to 10067 °U.

Some general information about temperatures in DF (copied from somewhere on the forums):

Event / location	Temperature
alcohol freezes	9850 °U
water freezes	10000 °U
underground	10015 °U
outside (varies)	10048 °U
dwarf/human body temp	10067 °U
floor above magma	10075 °U
fat melts	10078 °U
water boils	10180 °U
material is fire-safe	11000 °U
common stone melts	11500 °U
burning item (max)	11640 °U
magma	12000 °U

Melting point

This is the temperature at which a liquid material will melt, or a solid material will freeze. In Dwarf Fortress, the melting point and freezing point coincide exactly — this is contrary to many real-life materials, which can be supercooled.

Boiling point

This is the temperature at which the material will boil or condense. Water boils at 10180 °U.

Ignition point

This is the temperature at which the material will catch fire.

Heat damage point

This is the temperature above which the material will begin to take heat damage. Burning items without a heat damage point (or with an exceptionally high one) will take damage very slowly, causing them to burn for a very long time (9 months and 16.8 days) before disappearing.

Cold damage point

This is the temperature below which the material will begin to take frost damage.

Specific heat

This determines how long it takes the material to heat up or cool down. A material with a high specific heat capacity will hold more heat and affect its surroundings more before cooling down or heating up to equilibrium.

Fixed temperature

A material's temperature can be forced to always be a certain value via the MAT_FIXED_TEMP material definition token. The only standard material which uses this is nether-cap wood, whose temperature is always at the melting point of water. If a material's temperature is fixed to between its cold damage point and its heat damage point, then items made from that material will never suffer cold/heat damage. This makes nether-caps fire-safe and magma-safe despite being a type of wood.

Due to the way fixed temperature is handled, giving a material a fixed temperature will not cause its actual temperature to change accordingly — instead, its temperature will simply be permanently locked at whatever it was previously. Removing a material's fixed temperature, however, will cause all items made of it to heat or cool until reaching equilibrium with their surroundings.

The fixed temperature of a container has no effect on its contents, so you can't freeze water by putting it into a bucket made from nether-cap. Note that, presumably because Dwarf Fortress does not precisely simulate the process of freezing, water will not freeze at 10000 °U, instead requiring a temperature just a tiny bit lower.

The fixed temperature of an inorganic material has no effect on unmined walls made from that material, though boulders will take on that temperature as they are produced via mining.

@@ Line 154: / Line 154: @@
 Due to the way fixed temperature is handled, giving a material a fixed temperature will not cause its actual temperature to change accordingly &mdash; instead, its temperature will simply be permanently locked at whatever it was previously. Removing a material's fixed temperature, however, will cause all items made of it to heat or cool until reaching equilibrium with their surroundings.
-The fixed temperature of a [[container]] has no effect on its contents, so you can't freeze [[water]] by putting it into a [[bucket]] made from nether-cap. Note that, presumably because Dwarf Fortress does not simulate the enthalpy of freezing, water will not freeze anyway at {{ct|10000}}, instead requiring a temperature just a tiny bit lower.
+The fixed temperature of a [[container]] has no effect on its contents, so you can't freeze [[water]] by putting it into a [[bucket]] made from nether-cap. Note that, presumably because Dwarf Fortress does not precisely simulate the process of freezing, water will not freeze at {{ct|10000}}, instead requiring a temperature just a tiny bit lower.
 The fixed temperature of an inorganic material has no effect on unmined walls made from that material, though boulders '''will''' take on that temperature as they are produced via mining.