Traffic Behavior (beTraffic) makes an entity behave as a vehicle. Its parameters defines vehicle properties (size, speeds and accelerations). 

Traffic behavior in the behavior editor

For more information on traffic in Golaem Crowd, see Traffic Locator & Traffic tutorial

To use a Traffic Behavior, a Traffic Locator is mandatory. A Traffic Behavior uses the Traffic Locator Locator attached to its related CrowdField.

To define a goal for the car, see Traffic Goto.

The car size in the simulation, is defined by the Entity Type Attribute / Traffic Attribute section.

Even without Traffic Goto Behavior, each entity will wander randomly on the reachable roads from its position. When started, the entity is moved to the closest position on lanes, and its orientation is matched to the chosen lane. By default, it will be adapted on the ground if available, or it will be placed on the matching curve height if there is no ground, or if there is no adaptation asked. 


  • Behavior Editor / Behavior Library: 
  • Golaem Menu: Crowd Behaviors / Behaviors / CrowdBe Traffic Node
  • MEL command: glmCrowdBeTrafficCmd;


A Traffic Behavior defines the following specific attributes. For common attributes see Behavior Common Attributes.

Traffic Attributes

attributes of a Traffic Behavior

A vehicle is defined by its size (length & width in meters). It also have some acceleration / deceleration properties and speed limits.

Note that length and width must include any desired static safety distance when the car is stopped.

All the speeds and acceleration parameters can be multiplied by a random ratio, provided as min/max limits or ppAttributes.

Max Speed

Maximum speed that the car can reach in optimal conditions (sufficient time with no obstacle)

Speed When Turning

This is the speed the car should adopt when turning on a sharp turn (the car adapts its speed when the road is more curvy)

Max Acceleration

The maximum acceleration that the car should respect (m.s-2)

Max Deceleration

The maximum deceleration that the car should respect when braking (m.s-2)

Max Angular Speed

When the car should turn from a big amount at once, this parameter insures that the car is not exceeding this angular speed (degrees per second), else it will span the change on several frames.

Speeds Ratio Mode

Speeds and accelerations multiplier mode : could be random, or per particle attribute. If no randomization is desired, just set min & max to 1

Speeds Ratio Min

Minimum bound of random speed and accelerations ratio (in random mode)

Speeds Ratio Max

Maximum bound of random speed and accelerations ratio (in random mode)

Speeds Ratiopp Name

The name of the per particle attribute, if using a per particle speeds and accelerations ratio.

Advanced Attributes

Advanced Attributes of the Traffic behavior

Rotation Pivot Offset

Usually, the length is spanned evenly on the front and the back of the pelvis, as configured in the Character Maker. Thus, if the pelvis is not positioned at the center of the vehicle meshes (thus rotation pivot not centered), this attribute will offset the front / back to match the reality :

  • If your pelvis is closer from the back of the car, set this attribute as the POSITIVE distance between pelvis and the center of the meshes
  • If you pelvis is closer from the front of the car, set this attribute as the NEGATIVE distance between pelvis and the center of the meshes