VehicleBody3D

Inherits: RigidBody3D < PhysicsBody3D < CollisionObject3D < Node3D < Node < Object

A 3D physics body that simulates the behavior of a car.

Description

This physics body implements all the physics logic needed to simulate a car. It is based on the raycast vehicle system commonly found in physics engines. Aside from a CollisionShape3D for the main body of the vehicle, you must also add a VehicleWheel3D node for each wheel. You should also add a MeshInstance3D to this node for the 3D model of the vehicle, but this model should generally not include meshes for the wheels. You can control the vehicle by using the brake, engine_force, and steering properties. The position or orientation of this node shouldn't be changed directly.

Note: The origin point of your VehicleBody3D will determine the center of gravity of your vehicle. To make the vehicle more grounded, the origin point is usually kept low, moving the CollisionShape3D and MeshInstance3D upwards.

Note: This class has known issues and isn't designed to provide realistic 3D vehicle physics. If you want advanced vehicle physics, you may have to write your own physics integration using CharacterBody3D or RigidBody3D.

Tutorials

• 3D Truck Town Demo

Properties

float	brake	0.0
float	engine_force	0.0
float	mass	40.0 (overrides RigidBody3D)
float	steering	0.0

---

Property Descriptions

float brake = 0.0 🔗

• void set_brake(value: float)

• float get_brake()

Slows down the vehicle by applying a braking force. The vehicle is only slowed down if the wheels are in contact with a surface. The force you need to apply to adequately slow down your vehicle depends on the RigidBody3D.mass of the vehicle. For a vehicle with a mass set to 1000, try a value in the 25 - 30 range for hard braking.

---

float engine_force = 0.0 🔗

• void set_engine_force(value: float)

• float get_engine_force()

Accelerates the vehicle by applying an engine force. The vehicle is only sped up if the wheels that have VehicleWheel3D.use_as_traction set to true and are in contact with a surface. The RigidBody3D.mass of the vehicle has an effect on the acceleration of the vehicle. For a vehicle with a mass set to 1000, try a value in the 25 - 50 range for acceleration.

Note: The simulation does not take the effect of gears into account, you will need to add logic for this if you wish to simulate gears.

A negative value will result in the vehicle reversing.

---

float steering = 0.0 🔗

• void set_steering(value: float)

• float get_steering()

The steering angle for the vehicle. Setting this to a non-zero value will result in the vehicle turning when it's moving. Wheels that have VehicleWheel3D.use_as_steering set to true will automatically be rotated.

Note: This property is edited in the inspector in degrees. In code the property is set in radians.