Processors¶

These control how zombies move around on the virtual map. Each processor has a Power setting (how strong it is) and some have a Distance setting (how far away it works).

Behaviors That Make Zombies Group Together¶

FlockAnyGroup¶

Zombies move toward any nearby zombies.

Uses Distance: Yes
Example: Makes all zombies cluster together into one big group

FlockSameGroup¶

Zombies move toward other zombies in their own group only.

Uses Distance: Yes
Example: Keeps zombies with the same behavior together

FlockOtherGroup¶

Zombies move toward zombies in different groups.

Uses Distance: Yes
Example: Makes different zombie groups merge together

Behaviors That Make Zombies Move the Same Direction¶

AlignAnyGroup¶

Zombies face the same direction as nearby zombies.

Uses Distance: Yes
Example: Creates a horde all walking the same way

AlignSameGroup¶

Zombies face the same direction as zombies in their group.

Uses Distance: Yes
Example: Makes group members move together like a unit

AlignOtherGroup¶

Zombies face the same direction as zombies in other groups.

Uses Distance: Yes
Example: Makes different groups copy each other's direction

Behaviors That Make Zombies Spread Out¶

AvoidAnyGroup¶

Zombies move away from any nearby zombies.

Uses Distance: Yes
Example: Spreads zombies out across the map

AvoidSameGroup¶

Zombies move away from zombies in their own group.

Uses Distance: Yes
Example: Makes groups spread out without bunching up

AvoidOtherGroup¶

Zombies move away from zombies in different groups.

Uses Distance: Yes
Example: Makes groups stay separate from each other

Behaviors Using Wind¶

Wind¶

Zombies move in the direction the wind is blowing.

Uses Distance: No
Example: Zombies drift with the wind

WindInverted¶

Zombies move against the wind direction.

Uses Distance: No
Example: Zombies push against the wind

Behaviors Using Roads¶

StickToRoads¶

Zombies navigate along roads using a waypoint graph built from the map's road data. When near a road, agents follow it node-to-node. At intersections they pick a direction (usually continuing forward, sometimes turning). At dead ends they turn around and walk back to the last intersection. Agents that drift too far from their target road node will re-acquire the nearest road.

Uses Distance: No
Example: Zombies walk along roads and highways, properly traversing intersections and turning around at dead ends

AvoidRoads¶

Zombies move away from roads.

Uses Distance: No
Example: Zombies stay in the wilderness away from roads

Behaviors Using Buildings¶

StickToPOIs¶

Zombies move toward the nearest building or landmark.

Uses Distance: No
Example: Zombies gather at towns, gas stations, and houses

AvoidPOIs¶

Zombies move away from buildings.

Uses Distance: Yes
Example: Zombies avoid populated areas

Behaviors Using Cities¶

PreferCities¶

Zombies prefer to stay in cities. When inside a city, they wander naturally throughout the area. When outside, they move toward the nearest city.

Uses Distance: No
Example: Zombies congregate in towns and cities, creating realistic population centers

AvoidCities¶

Zombies avoid cities and stay in the wilderness. When inside a city, they push toward the nearest exit. When outside, they move away from city boundaries.

Uses Distance: Yes
Example: Zombies avoid populated areas and are found in forests, mountains, and rural areas

CityVisitor¶

Zombies travel to cities using a stateful behavior with three phases: selecting a target city, traveling to it, and exploring it before selecting a new destination. The stay duration is configurable via Param1 (minimum) and Param2 (maximum), specified in real-time minutes.

How it works: - Idle Phase: Selects a random target city using weighted selection (larger cities are more likely to be chosen) - Approaching Phase: Travels toward the target city until arrival - Arrived Phase: Explores the city for a random duration between Param1 and Param2 real-time minutes with hash-based wandering patterns that change every 60 seconds, then returns to Idle

The selection is deterministic based on agent group and current time, causing agents to pick new destinations at different times. Unlike PreferCities (which keeps agents in one general area), CityVisitor makes agents migrate between cities, creating dynamic population shifts across the map.

Uses Distance: No
Example: Zombie groups travel between cities, spending 20 minutes exploring before moving to the next destination

Behaviors Using Biomes¶

These processors use a signed distance field (SDF) computed from the map's biome data to attract or repel agents toward specific biome types. A Biome parameter selects which biome to target: Snow, Pine Forest, Desert, Wasteland, or Burnt Forest.

The force is proportional to how far the agent is from the biome boundary — stronger when far away, tapering to zero at the edge to prevent overshooting.

StickToBiome¶

Zombies are attracted toward a specific biome. Agents outside the target biome are pulled toward it. Once inside, a gentle nudge near the boundary keeps them from drifting out, while deep inside no force is applied so other processors drive movement freely.

Uses Distance: No
Uses Biome: Yes (select target biome type)
Example: Zombies stay in the desert, creating biome-specific population zones

AvoidBiome¶

Zombies are repelled from a specific biome. Agents inside the target biome are pushed out. Once outside, no force is applied.

Uses Distance: No
Uses Biome: Yes (select target biome type)
Example: Zombies avoid snowy areas and stay in warmer biomes

Example Settings¶

Here's how to set up zombie behaviors in your config file:

<Systems>
  <System Weight="2" SpeedScale="1.0" PostSpawnBehavior="Wander" Color="#FF0000">
    <Processor Type="FlockSameGroup" Distance="15.0" Power="0.6" />
    <Processor Type="AvoidRoads" Power="0.4" />
  </System>
  <System Weight="1" SpeedScale="1.5" PostSpawnBehavior="ChaseActivator" Color="#00FF00">
    <Processor Type="WorldEvents" Power="0.8" />
    <Processor Type="StickToPOIs" Power="0.5" />
  </System>
  <System Weight="1" SpeedScale="1.0" PostSpawnBehavior="Wander" Color="#FFFF00">
    <Processor Type="PreferCities" Power="0.7" />
    <Processor Type="FlockSameGroup" Distance="20.0" Power="0.4" />
  </System>
  <System Weight="1" SpeedScale="1.2" PostSpawnBehavior="Wander" Color="#00FFFF">
    <Processor Type="StickToBiome" Power="0.5" Param1="5" />
    <Processor Type="AvoidCities" Distance="100.0" Power="0.8" />
  </System>
  <System Weight="1" SpeedScale="1.0" PostSpawnBehavior="Wander" Color="#FF00FF">
    <Processor Type="CityVisitor" Power="0.9" Param1="15" Param2="30" />
  </System>
</Systems>

This creates five systems with groups distributed by weight:

System 1 (weight 2, gets most groups): Zombies stick together in groups, avoid roads, and wander randomly
System 2: Zombies go to buildings, chase loud noises, move faster, and chase you when they spawn
System 3: Zombies prefer cities, congregate in towns, and stay in groups
System 4: Zombies stick to the desert biome and avoid cities
System 5: Zombies visit cities in rotation, migrating between different population centers

Understanding Power and Distance¶

Power: How strong the behavior is - 0.5 = weak effect - 1.0 = medium effect - 2.0 = strong effect

Distance: How far away (in meters) the behavior works - 10.0 = only affects very close zombies - 50.0 = affects zombies far away - Only some behaviors use this setting

Tips¶

Start with Power values around 0.5 to 1.0, then adjust
You can combine multiple behaviors (like FlockSameGroup + StickToPOIs)
Higher Power values = stronger behavior
Behaviors without Distance work on the whole map or use their own range