- 1 Effects of Heatmap
- 2 Things that Affects Heatmap
- 3 Compounding Effects
- 4 Notes and References
The Heatmap is a mechanic that controls the spawn of zombies depending on the player's activities. It does not have a literal implication towards temperature but it does affect a certain area around the affected zone. It may be easier to think of this as a measurement of the activity level in a given area. The higher the activity level, the more likely zombies will appear.
Every chunk (a 16 X 16 block area) has a heat level value and various activities can increase the heat level. Heat generated in a chunk affects that chunk and all adjacent chunks. Once the heat-generating activity stops, the heat level will decrease slowly over time.
To see the heat level of the chunk that the player is in, activate debug mode, and press F8.
Effects of Heatmap[edit | edit source]
If the player performs certain activities in a small area, the heat of that area will increase. If the heat level is high enough, there is a chance that it will be set to around half of its value and a certain event will happen near the affected zone. The higher the heat of an area, the more likely that such an event will happen. 100 points will instantly reset the counter.
Scouting Zombie[edit | edit source]
Formerly done by the Spider Zombie, scouting is now performed by Screamer, which after spawning, will wander around the affected area. If they spot a player in the area they will emit screams, which will then spawn random zombies around it, possibly even a horde if the screamers are not defeated fast enough.
Even if the screamer does not notice the player, it's always preferable to dispose of it quickly, because it will start summoning zombies by itself when it has scouted for too long and has decided to storm the player's heatmap-generating object instead.
Pitstop Horde[edit | edit source]
Pitstop hordes are similar to a wandering horde, but these only happen if the heatmap got reset too many times. Pitstop horde has varied difficulty and is dependent on the reset frequency and may even spawn Special Infected that may cause trouble for the player. Unlike the wandering horde, pitstop horde will walk directly toward the source of the heatmap, and will eventually seek to break the player's door and destroy the source whether it's the player's campfire, workbench, chemistry station, or much more. Pitstop horde event will never happen during the blood moon, and they will never include a screamer.
Things that Affects Heatmap[edit | edit source]
Using Objects[edit | edit source]
Using the following items will generate heat:
Note: If you are looking to purposely generate as much heat as possible, and draw the maximum amount of zombies to a specified area, then 25 campfires fully loaded with wood will consistently reach, and maintain the heat map at 100%, drawing extremely large amounts of zombies, once it reaches 100% you can turn 5 of them off, as you will no longer need the additional boost to maintain the heatmap at 100%. Note: This is also very likely to be changed at some point in the future, making too much activity draw full on hordes to the player's area.
|AK-47 Assault Rifle||0.3||120|
|Air Filter Land Mine||5||120|
|Cooking Pot Mine||5||120|
|Hub Cap Land Mine||5||120|
|Iron Door1 v2||0.05||120|
|Iron Door1 v3||0.05||120|
|Iron Hatch v2||0.05||120|
|Iron Hatch v3||0.05||120|
|Pressure Plate Mine||5||120|
|Stick of Dynamite||5||120|
|Tin Land Mine||5||120|
|Vault Door v2||0.05||120|
|Vault Door v3||0.05||120|
Firearms and explosives generate heat on a per-use basis. Other items continue to generate heat as they are used, such Campfires and forges. Therefore some items have an additional value of "frequency."
In the file blocks.xml, the frequency is defined as a number of ticks. Each tick is approximately a .75 to 1 minute real-time interval. Therefore, according to the table above, each forge running will generate 1.5 units of heat every 18.75-25 real-time minutes, and will stack up as the forge runs. These 1.5 units of heat will only disappear once the its HeatMapTime of 1200 is reached, which is approximately after 33 real-time minutes.
In the file Stealth.txt, heat map time is defined as "the time in seconds it takes for the heat to dissipate. Dissipation is not modeled, it's instant off after the time." However, it is either contradicted and/or clarified in blocks.xml that HeatMapTime decays in x seconds, and scales with game time. It further states that HeatMapTime 36 roughly equals 1 minute (presumably at default [50 minute] day length).
Combat[edit | edit source]
Killing a zombie in a direct, non-stealth engagement will cause it to scream upon its death, which not only may attract the attention of nearby zombies, but will also add to the total heatmap points, which may result in even more zombies spawning near the player.
Passive Action[edit | edit source]
Any activity which includes staying in one place for too long will passively increase the heatmap (eg: camping, base building, or generally hiding). However, building any number of block or furniture won't affect the heatmap, but spending too much time doing so will increase the heat map.
Player bed (Spawn Point, also contributes to increasing the heatmap passively.)
Crimes Against Nature[edit | edit source]
Felling one or two trees will affect nothing, but chopping down many trees within a small area will exponentially attract more zombies, using loud tools like a chainsaw will also accumulate points toward the heatmap pool, same goes for mining too much and digging large holes.
Farming and gathering do not affect the heatmap however.
Hunting, while killing Animals using bows will not generate heat, their corpse upon harvesting will leave a pile of gore which will passively generate massive amounts of heat, even if it's disposed of very quickly, it will still have created a rather high amount of heat.
Metallic Objects[edit | edit source]
Dismantling with a wrench or damaging a metallic object using another metal tool increases the heatmap with each hit. Using tools with higher block damage will result in less heat from hitting the object fewer times. Lockpicking safes also increases heatmap, but at an even higher rate due to the high durability of safes.
Upgrading and constructing using metals will also increase the heatmap. This counts for building scrap blocks and upgrading blocks and doors to their metallic tiers.
Horde Mentality[edit | edit source]
This is another problem that some players may encounter, usually those who chose to shelter in only one place. Even if no heatmap-generating actions are done around this place, zombies may still spawn and approach the player. The heatmap would just progressively increase more and more rapidly over time. While it is possible that zombies, as a collective, take note of where the player usually hangs around as they keep trying to get to the player, this may also be part of the compounding effect where zombies being killed generates heat, which spawns in more zombies, and then the spawned zombies are killed, and so on.
Other Actions[edit | edit source]
- Falling Down - falling down one block will not affect the heatmap, but falling down any further will increase the heatmap at 0.5 point.
- Jumping - Jumping is similar to falling down, but jumping will always increase the heatmap by 0.05 point no matter how low the landing point is.
- Breaking Glass - Breaking glass objects, especially windows will increase the heatmap by 0.5 point during its destruction.
- Riding Bike - While not easily noticeable, the minibike does generate heatmap when driven around, but it does not necessarily attract zombies' attention to it.
- Torch & Candles - These object do affect the heatmap, the candle by 1 point and the Torch by 4.05 points.
- Burning Barrel - increases heatmap by 4.05.
- Doors - Opening or closing doors/hatches upgraded with metal increases the heatmap by 0.5 point each use.
What Does NOT Increase Heatmap[edit | edit source]
- Running - It does not increase heatmap, but will still generate noise that may attract nearby zombies.
- Destruction, Upgrades, and Construction of Wooden and Stone (Flagstone, Brick, Concrete) Objects.
- Non-Fire based light sources, such as spotlights.
- Electrical Traps - Although it's possibly a bug, gunshots generated by electrical traps do not increase the heatmap nor will its sound ever attract nearby zombies.
- Speaker - While this also might be a bug, not only do speakers not generate any heat, they do not attract or even redirect zombies near it.
- Smell - While smell does attract nearby zombies via a separate mechanic, carrying an item which smells will not alter the heatmap. (Smell mechanics have been disabled since A16.3 due to problems but is expected to be fixed in A17)
Compounding Effects[edit | edit source]
Each individual item or action affecting the heatmap adds to the heat level. Thus multiple Campfires or forges compound the increase in heat for a given area. Also, a single item's generated heat levels are compounded over time. A single campfire used for a long duration will eventually build a high level of heat.
Because it takes time for heat levels to naturally decrease and because the action of fighting zombies—especially with firearms and explosives—also generates heat, it is possible to get caught in a cycle in which screamers continue to spawn to investigate and attract additional zombies.
Notes and References[edit | edit source]
- sounds.xml and blocks.xml define an item or block's heat signature using the parameters HeatMapStrength, HeatMapTime, and HeatMapFrequency
- How heat is calculated over time for the chainsaw and auger needs to be determined