Boids Entities

Overview

Boids exist only as an atmospheric entity, to add life and ambiance to the level. Boid entities simulate living animal objects that have simulated group behavior and obstacle avoidance.

Their complex behavior arises from the interaction of an individual agent (Boid) with other agents and the environment that they are moving in.

For information on setting up Boids from an Asset Creation perspective, see Boids (animated).

Placing Boids as an Entity

Alternatively, you can place the Boid as an Entity from the Entity tab. On the RollupBar, open the folder that contains the animal you want and drag it to the scene.

If the animal isn't displayed immediately, move the camera a good distance away from the Archetype Entity and then zoom it back in. If this also fails to display the animal, save and reload the level.

Ambient animals cannot be directly controlled, but can be interacted with, by the player. They come complete with sound effects and a simple flocking behavior.

Boid Entity Properties

It is important to note that when referencing available parameters below that not all parameters are available for all boid classes.

For example, Behavior classes are only needed for the Bugs boid class and don't appear in other Boid properties.

Boid

Property

Description

Animation

Deprecated

Behavior

This sets the movement behavior for the boid entity.

  • 0 = Generic ground bug e.g. beetles
  • 1 = Flying insects e.g. dragonflies
  • 2 = Leaping insects e.g. grasshoppers

Count

The Count number specifies how many individual objects will be spawned.

gravity_at_death

Gravity acceleration that affects the body of the killed boid.

Invulnerable

Specifies whether the boid can be killed or not.

Mass

Mass of each individual boid.

Model

Geometry for the boid, can be a character (.CHR) or static geometry (.CGF).

Model1-5

Additional geometry for the boid, can be a character (.CHR) or static geometry (.CGF). If you specify more than one option the geometry will be selected at random.

Flocking

Property

Description

AttractDistMax

Maximal distance at which one boid can see another boid. Boids that are too far away will not be interacted with.

AttractDistMin

Minimal distance that boids are comfortable to stay close to each other before the separation force starts to affect them.

EnableFlocking

When enabled, the rules of the emergent flocking behavior will be calculated on the whole flock of boids.

FactorAlign

Steer towards the average heading of local flock-mates.

FactorCohesion

Steer to move toward the average position of local flock-mates.

FactorSeperation

Steer to avoid crowding local flock-mates, only when closer then AttractDistMin.

FieldOfViewAngle

Field of vision of the boid to consider other boids as flock-mates.

Ground

Note that these properties only apply when boids are walking on the ground. Boids will only be able to land in game mode and not while editing.

Property

Description

FactorAlign

The alignment calculation tries to ensure that all boids move in roughly the same direction.

FactorCohesion

The cohesion calculation tries to ensure that boids group together.

FactorOrigin

This origin factor controls how much boids are attracted to their point of origin.

FactorSeparation

The separation calculation tries to ensure that boids avoid one another.

HeightOffset

Vertical offset of boids from the ground.

OnGroundIdleDurationMax

Maximum time boids will spend in idle state.

OnGroundIdleDurationMin

Minimum time boids will spend in idle state.

OnGroundWalkDurationMax

Maximum time boids will spend in walk state.

OnGroundWalkDurationMin

Minimum time boids will spend in walk state.

WalkSpeed

Walk speed when boids land.

WalkToIdleDuration

Time it takes for boids to transition from walking to idle state.

Movement

Property

Description

FactorAvoidLand

Force coefficient to divert boid from the land or water.

FactorHeight

Controls the force that is applied to keep boids at the original height for the flock.

FactorOrigin

Controls the force that attract boids to the origin point of the flock.

FactorTakeOff

Vertical movement speed scale during take-off.

FlightTime

Approximate flight time before attempting to land.

HeightMax

Maximal height boids can fly to (Height above land).

HeightMin

Minimal height boid can fly at (Height above land).

LandDecelerationHeight

Height at which boids will start to decelerate when landing.

MaxAnimSpeed

If the boid had animations, then you can use this variable to control the speed of the animation

SpeedMax

Maximal speed that boid can move with.

SpeedMin

Minimal speed that boid can move with.

Options

Property

Description

Activate

When checked active boids are visible and move from the start of the level, alternatively boids can be activated at later stage with the activate event.

AnimationDist

Maximum distance from camera at which animations will update.

FollowPlayer

When checked boids will only wrap around current player position, flock origin point becomes the player position.
If the boid flies too far away from the player, they will reappear on the opposite side.

NoLanding

Turns landing for birds flocks on/off.

ObstacleAvoidance

Boids will sense the physical environment and be diverted from the physical obstacles.
This option adds heavier physical checks on the boids and should be used carefully only when really needed.

Radius

Maximum radius the boid can move from the flock origin point.

SpawnFromPoint

If set to true all the boids will spawn at the boid entity position.

StartOnGround

If true boids will spawn on the ground, otherwise they will spawn in the air.

VisibilityDist

Maximal distance from which whole flock can be visible.
If player camera is further away from flock origin than Visibility Distance boids will not be simulated and rendered.

ParticleEffects

Property

Description

EffectScale

Scale of the particle effect to be played.

waterJumpSplash

Particle effect to be played when the boid splashes into the water.