env_fire

Code classes:

• CFire
• CBaseEntity (all ents)

env_fire is a point entity present in all Source games. It handles a single flame (_firesmoke) at its origin. The flame causes heat "damage" to other entities around it, and will eventually ignite them and other env_fires.

Note: The entity attempts to always place itself directly onto the ground by "dropping" down. The fire may fall through the world if placed exactly at ground level. Place it a little bit above the ground to fix this.

Tip: To make fires appear like they're pointing horizontally, parent them to a rotating object.

Bug: This entity doesn't display correctly in . See here for more details.

Bug: While still available, it does not have particle effects in . See here.

Bug: In , an env_fire cannot be extinguished with the fire extinguisher unless Infinite Duration is set.

ConVars/Commands

ConVar/Command	Parameters or default value	Parameter Type	Effect
fire_maxabsorb	50	Arbitrary number	Upper limit for how much heat "damage" a fire can take before the damage begins to force the flame to grow. Heat is usually absorbed from other env_fires.
fire_absorbrate	3	Multiplier	Scalar for how fast fires can absorb heat.
fire_extscale	12	Multiplier	Effectively only a scalar for the Strength of an env_extinguisherjet.
fire_extabsorb	5	Multiplier	To do: Effect description.
fire_heatscale	1.0	Multiplier	Scalar for how much damage a fire can do (both to fires and other objects such as the player).
fire_incomingheatscale	0.1	Multiplier	Scalar for how much heat a fire can take from other fires if it is already ignited.
fire_dmgscale	0.1	Multiplier	To do: Effect description.
fire_dmgbase	1	Health Amount	Base damage that a fire does to objects such as the player. In some games this amount changes depending on the difficulty setting.
fire_growthrate	1.0	Multiplier	Scalar for how much heat a fire can passively add to itself at once. Thinking interval is 0.1 seconds.
fire_dmginterval	1.0	Seconds	Once a fire has damaged something, it will wait this long before it can damage anything again.

Flags

• 1: Infinite Duration

• 2: Smokeless (good FPS boost)

• 4: Start On - Starts ignited.

• 8: Start Full (makes the fire ignore heat from other entities)

• 16: Don't drop (disables the dropping behavior noted above)

• 32: No glow - No effect.

• 128: Delete when out (entity will remove itself after extinguishing)

• 256: Visible from above - No effect.

• 256: No sound (only available in )

• 512: No ignite sound (only available in )

• 1024: No fueling once lit (only available in )^[Clarify]

• 2048: Fast burn think (only available in )^[Clarify]

Keyvalues

Duration (health) <integer>

Amount of time the fire will burn.

Size (firesize) <integer>

Distance in which the fire can spread heat to other fire entities. Also scales the fire and smoke to look smaller or larger.

Attack (fireattack) <integer>

Amount of time the fire takes to grow to full strength.^[Confirmed]

Type (firetype) <choices>

Either Natural or Plasma. Natural is a general all purpose flame, like a wood fire.

• 0: Natural
• 1: Plasma (The particle effect for this type does not exist.)

Ignition Point (ignitionpoint) <float>

Amount of heat "damage" to take before this flame should ignite.

Damage Scale (damagescale) <float>

Multiplier of the burn damage done by the flame.

Light Color (LightColor) <color255> (only available in )

Color of dynamic light for this fire.

Light Radius Scale (LightRadiusScale) <float> (only available in )

Multiplier for the glow effect's size.

Light Brightness (LightBrightness) <integer> (only available in )

Exponent for the glow brightness.

Loop sound (LoopSound) <sound> (only available in )

Looping sound to play while this fire is burning.

Ignite sound (IgniteSound) <sound> (only available in )

One shot sound to play when the fire starts.

Start Disabled (StartDisabled) <boolean>

Stay inactive until Enabled.

Note: Disabled means it cannot catch on fire by any means.

Inputs

StartFire

Start the fire.

Extinguish <float>

Puts out the fire permanently after the number of seconds specified.

ExtinguishTemporary <float>

Puts out the fire temporarily after the number of seconds specified.

Enable

Makes the entity active.

Disable

Makes the entity inactive.

Outputs

OnIgnited

Fires when the fire is first ignited.

OnExtinguished

Fires when the fire is fully extinguished.