2D Physics Engine Reference

The 2D physics engine simulates realistic object physics, with gravity, forces, collisions, joints, etc. It's perfect for 2D games that need to have realistic behaving objects and a gameplay centered around it.

Objects like floors or wall objects should usually be set to "Static" as type. Objects that should be moveable are usually "Dynamic" (default). "Kinematic" objects (typically, players or controlled characters) are only moved by their "linear velocity" and "angular velocity" - they can interact with other objects but only these other objects will move.

Forces (and impulses) are expressed in all conditions/expressions/actions of the 2D physics engine in Newtons (N). Typical values for a force are 10-200 N. One meter is 100 pixels by default in the game (check the world scale). Mass is expressed in kilograms (kg). Read more explanations about it.

Actions

World time scale
Modify the world time scale. While an object is needed, this will apply to all objects using the behavior.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Time scale (1 by default)

Conditions

Collision
Check if two objects collide.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 👾 Object

Technical note: parameter 3 are internal parameters handled by GDevelop.

Collision started
Check if two objects just started colliding during this frame.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 👾 Object

Technical note: parameter 3 are internal parameters handled by GDevelop.

Collision stopped
Check if two objects just stopped colliding at this frame.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 👾 Object

Technical note: parameter 3 are internal parameters handled by GDevelop.

2D Physics Engine

Simulate realistic 2D physics for the object including gravity, forces, collisions, and joints.

Behavior actions

Add distance joint
Add a distance joint between two objects. The length is converted to meters using the world scale on X. The frequency and damping ratio are related to the joint speed of oscillation and how fast it stops.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Length (-1 to use current objects distance) (default: -1)
• Parameter 8 (🔢 Number): Frequency (Hz) (non-negative) (default: 0)
• Parameter 9 (🔢 Number): Damping ratio (non-negative) (default: 1)
• Parameter 10 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 11 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add friction joint
Add a friction joint between two objects.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Maximum force (non-negative)
• Parameter 8 (🔢 Number): Maximum torque (non-negative)
• Parameter 9 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 10 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add gear joint
Add a gear joint between two joints. Attention: Gear joints require the joints to be revolute or prismatic, and both of them to be attached to a static body as first object.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): First joint ID
• Parameter 3 (🔢 Number): Second joint ID
• Parameter 4 (🔢 Number): Ratio (non-zero) (default: 1)
• Parameter 5 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 6 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add motor joint
Add a motor joint between two objects. The position and angle offsets are relative to the first object.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (👾 Object): Second object
• Parameter 3 (🔢 Number): Offset X position
• Parameter 4 (🔢 Number): Offset Y position
• Parameter 5 (🔢 Number): Offset Angle
• Parameter 6 (🔢 Number): Maximum force (non-negative)
• Parameter 7 (🔢 Number): Maximum torque (non-negative)
• Parameter 8 (🔢 Number): Correction factor (default: 1)
• Parameter 9 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 10 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add mouse joint
Add a mouse joint to an object (makes the object move towards a specific point).

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Target X
• Parameter 3 (🔢 Number): Target Y
• Parameter 4 (🔢 Number): Maximum force (N) (non-negative) (default: 500)
• Parameter 5 (🔢 Number): Frequency (Hz) (positive) (default: 10)
• Parameter 6 (🔢 Number): Damping ratio (non-negative) (default: 1)
• Parameter 7 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add prismatic joint
Add a prismatic joint between two objects. The translation limits are converted to meters using the world scale on X.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Axis angle
• Parameter 8 (🔢 Number): Reference angle (default: 0)
• Parameter 9 (❓ Yes or No): Enable limits? (default: no)
• Parameter 10 (🔢 Number): Minimum translation (default: 0)
• Parameter 11 (🔢 Number): Maximum translation (default: 0)
• Parameter 12 (❓ Yes or No): Enable motor? (default: no)
• Parameter 13 (🔢 Number): Motor speed (default: 0)
• Parameter 14 (🔢 Number): Motor maximum force (default: 0)
• Parameter 15 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 16 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add pulley joint
Add a pulley joint between two objects. Lengths are converted to meters using the world scale on X.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Ground anchor X for first object
• Parameter 8 (🔢 Number): Ground anchor Y for first object
• Parameter 9 (🔢 Number): Ground anchor X for second object
• Parameter 10 (🔢 Number): Ground anchor Y for second object
• Parameter 11 (🔢 Number): Length for first object (-1 to use anchor positions) (default: -1)
• Parameter 12 (🔢 Number): Length for second object (-1 to use anchor positions) (default: -1)
• Parameter 13 (🔢 Number): Ratio (non-negative) (default: 1
• Parameter 14 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 15 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add revolute joint
Add a revolute joint to an object at a fixed point. The object is attached as the second object in the joint, so you can use this for gear joints.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): X anchor
• Parameter 3 (🔢 Number): Y anchor
• Parameter 4 (❓ Yes or No): Enable angle limits? (default: no)
• Parameter 5 (🔢 Number): Reference angle (default: 0)
• Parameter 6 (🔢 Number): Minimum angle (default: 0)
• Parameter 7 (🔢 Number): Maximum angle (default: 0)
• Parameter 8 (❓ Yes or No): Enable motor? (default: no)
• Parameter 9 (🔢 Number): Motor speed (default: 0)
• Parameter 10 (🔢 Number): Motor maximum torque (default: 0)
• Parameter 11 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add revolute joint between two bodies
Add a revolute joint between two objects. The reference angle determines what is considered as the base angle at the initial state.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (❓ Yes or No): Enable angle limits? (default: no)
• Parameter 8 (🔢 Number): Reference angle (default: 0)
• Parameter 9 (🔢 Number): Minimum angle (default: 0)
• Parameter 10 (🔢 Number): Maximum angle (default: 0)
• Parameter 11 (❓ Yes or No): Enable motor? (default: no)
• Parameter 12 (🔢 Number): Motor speed (default: 0)
• Parameter 13 (🔢 Number): Motor maximum torque (default: 0)
• Parameter 14 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 15 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add rope joint
Add a rope joint between two objects. The maximum length is converted to meters using the world scale on X.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Maximum length (-1 to use current objects distance) (default: -1)
• Parameter 8 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 9 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add weld joint
Add a weld joint between two objects.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Reference angle (default: 0)
• Parameter 8 (🔢 Number): Frequency (Hz) (non-negative) (default: 10)
• Parameter 9 (🔢 Number): Damping ratio (non-negative) (default: 1)
• Parameter 10 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 11 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Add wheel joint
Add a wheel joint between two objects. Higher frequencies means higher suspensions. Damping determines oscillations, critical damping of 1 means no oscillations.

See parameters

• Parameter 0 (👾 Object): First object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Anchor X on first body
• Parameter 3 (🔢 Number): Anchor Y on first body
• Parameter 4 (👾 Object): Second object
• Parameter 5 (🔢 Number): Anchor X on second body
• Parameter 6 (🔢 Number): Anchor Y on second body
• Parameter 7 (🔢 Number): Axis angle
• Parameter 8 (🔢 Number): Frequency (Hz) (non-negative) (default: 10)
• Parameter 9 (🔢 Number): Damping ratio (non-negative) (default: 1)
• Parameter 10 (❓ Yes or No): Enable motor? (default: no)
• Parameter 11 (🔢 Number): Motor speed (default: 0)
• Parameter 12 (🔢 Number): Motor maximum torque (default: 0)
• Parameter 13 (❓ Yes or No): Allow collision between connected bodies? (default: no)
• Parameter 14 (🗄️ Scene variable): Variable where to store the joint ID (default: none)

Angular damping
Modify an object angular damping. How much angular speed is lost across the time.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Value

Angular velocity
Modify an object angular velocity.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Angular speed (in degrees per second)

Apply angular impulse (rotational impulse)
Apply an angular impulse (also called a "rotational impulse") to the object. It instantly changes the rotation speed, to give an initial speed for instance.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Angular impulse (N·m·s) An impulse is like a rotation speed addition but depends on the mass.

Apply force
Apply a force to the object over time. It "accelerates" an object and must be used every frame during a time period.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): X component (N)
• Parameter 3 (🔢 Number): Y component (N) A force is like an acceleration but depends on the mass.
• Parameter 4 (🔢 Number): Application point on X axis
• Parameter 5 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply force toward position
Apply a force to the object over time to move it toward a position. It "accelerates" an object and must be used every frame during a time period.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Length (N) A force is like an acceleration but depends on the mass.
• Parameter 3 (🔢 Number): X position
• Parameter 4 (🔢 Number): Y position
• Parameter 5 (🔢 Number): Application point on X axis
• Parameter 6 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply impulse
Apply an impulse to the object. It instantly changes the speed, to give an initial speed for instance.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): X component (N·s or kg·m·s⁻¹)
• Parameter 3 (🔢 Number): Y component (N·s or kg·m·s⁻¹) An impulse is like a speed addition but depends on the mass.
• Parameter 4 (🔢 Number): Application point on X axis
• Parameter 5 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply impulse toward position
Apply an impulse to the object to move it toward a position. It instantly changes the speed, to give an initial speed for instance.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Length (N·s or kg·m·s⁻¹) An impulse is like a speed addition but depends on the mass.
• Parameter 3 (🔢 Number): X position
• Parameter 4 (🔢 Number): Y position
• Parameter 5 (🔢 Number): Application point on X axis
• Parameter 6 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply force (angle)
Apply a force to the object over time using polar coordinates. It "accelerates" an object and must be used every frame during a time period.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Angle
• Parameter 3 (🔢 Number): Length (N) A force is like an acceleration but depends on the mass.
• Parameter 4 (🔢 Number): Application point on X axis
• Parameter 5 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply impulse (angle)
Apply an impulse to the object using polar coordinates. It instantly changes the speed, to give an initial speed for instance.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Angle
• Parameter 3 (🔢 Number): Length (N·s or kg·m·s⁻¹) An impulse is like a speed addition but depends on the mass.
• Parameter 4 (🔢 Number): Application point on X axis
• Parameter 5 (🔢 Number): Application point on Y axis Use MassCenterX and MassCenterY expressions to avoid any rotation.

Apply torque (rotational force)
Apply a torque (also called "rotational force") to the object. It "accelerates" an object rotation and must be used every frame during a time period.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Torque (N·m) A torque is like a rotation acceleration but depends on the mass.

Density
Modify an object density. The body's density and volume determine its mass.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Value

Distance joint damping ratio
Modify a distance joint damping ratio.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Distance joint frequency
Modify a distance joint frequency.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Distance joint length
Modify a distance joint length.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Enable layer
Enable or disable a layer for an object. Two objects collide if any layer of the first object matches any mask of the second one and vice versa.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Layer (1 - 16)
• Parameter 3 (❓ Yes or No): Enable

Enable mask
Enable or disable a mask for an object. Two objects collide if any layer of the first object matches any mask of the second one and vice versa.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Mask (1 - 16)
• Parameter 3 (❓ Yes or No): Enable

Enable prismatic joint limits
Enable or disable a prismatic joint limits.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (❓ Yes or No): Enable

Enable prismatic joint motor
Enable or disable a prismatic joint motor.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (❓ Yes or No): Enable

Enable revolute joint limits
Enable or disable a revolute joint angle limits.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (❓ Yes or No): Enable

Enable revolute joint motor
Enable or disable a revolute joint motor.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (❓ Yes or No): Enable

Enable wheel joint motor
Enable or disable a wheel joint motor.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (❓ Yes or No): Enable

Friction
Modify an object friction. How much energy is lost from the movement of one object over another. The combined friction from two bodies is calculated as 'sqrt(bodyA.friction * bodyB.friction)'.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Value

Friction joint max force
Modify a friction joint maximum force.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Friction joint max torque
Modify a friction joint maximum torque.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Gear joint ratio
Modify a Gear joint ratio.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

World gravity
Modify the world gravity. While an object is needed, this will apply to all objects using the behavior.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Gravity X
• Parameter 3 (🔢 Number): Gravity Y

Gravity scale
Modify an object gravity scale. The gravity applied to an object is the world gravity multiplied by the object gravity scale.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Scale (1 by default)

Linear damping
Modify an object linear damping. How much movement speed is lost across the time.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Value

Linear velocity towards an angle
Set the linear velocity towards an angle.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Angle
• Parameter 3 (🔢 Number): Speed (in pixels per second)

Linear velocity X
Modify an object linear velocity on X.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Speed (in pixels per second)

Linear velocity Y
Modify an object linear velocity on Y.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Speed (in pixels per second)

Motor joint angular offset
Modify a motor joint angular offset.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Motor joint correction factor
Modify a motor joint correction factor.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Motor joint max force
Modify a motor joint maximum force.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Motor joint max torque
Modify a motor joint maximum torque.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Motor joint offset
Modify a motor joint offset.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (🔢 Number): Offset X
• Parameter 4 (🔢 Number): Offset Y

Mouse joint damping ratio
Set a mouse joint damping ratio.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Mouse joint frequency
Set a mouse joint frequency.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Mouse joint max force
Set a mouse joint maximum force.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Mouse joint target
Set a mouse joint target.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (🔢 Number): Target X
• Parameter 4 (🔢 Number): Target Y

Prismatic joint limits
Modify a prismatic joint limits.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (🔢 Number): Minimum translation
• Parameter 4 (🔢 Number): Maximum translation

Prismatic joint max motor force
Modify a prismatic joint maximum motor force.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Prismatic joint motor speed
Modify a prismatic joint motor speed.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Remove joint
Remove a joint from the scene.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Restitution
Modify an object restitution. Energy conservation on collision. The combined restitution from two bodies is calculated as 'max(bodyA.restitution, bodyB.restitution)'.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Value

Revolute joint limits
Modify a revolute joint angle limits.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3 (🔢 Number): Minimum angle
• Parameter 4 (🔢 Number): Maximum angle

Revolute joint max motor torque
Modify a revolute joint maximum motor torque.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Revolute joint motor speed
Modify a revolute joint motor speed.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Rope joint max length
Modify a rope joint maximum length.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Treat as bullet
Treat the object as a bullet. Better collision handling on high speeds at cost of some performance.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (❓ Yes or No): Treat as bullet

Set as dynamic
Set an object as dynamic. Is affected by gravity, forces and velocities.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Fixed rotation
Enable or disable an object fixed rotation. If enabled the object won't be able to rotate.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (❓ Yes or No): Fixed rotation

Set as kinematic
Set an object as kinematic. Is like a static body but can be moved through its velocity.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Sleeping allowed
Allow or not an object to sleep. If enabled the object will be able to sleep, improving performance for non-currently-moving objects.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (❓ Yes or No): Can sleep

Set as static
Set an object as static. Is not affected by gravity, and can't be moved by forces or velocities at all.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Shape scale
Modify an object shape scale. It affects custom shape dimensions and shape offset, if custom dimensions are not set the body will be scaled automatically to the object size.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Operator
• Parameter 3 (🔢 Number): Scale (1 by default)

Weld joint damping ratio
Modify a weld joint damping ratio.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Weld joint frequency
Modify a weld joint frequency.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Wheel joint damping ratio
Modify a wheel joint damping ratio.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Wheel joint frequency
Modify a wheel joint frequency.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Wheel joint max motor torque
Modify a wheel joint maximum motor torque.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Wheel joint motor speed
Modify a wheel joint motor speed.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Operator
• Parameter 4 (🔢 Number): Value

Behavior conditions

Angular damping
Test an object angular damping.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Value to compare

Angular velocity
Test an object angular velocity.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Angular speed to compare to (in degrees per second)

Density
Test an object density.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Value to compare

Friction
Test an object friction.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Value to compare

Gravity scale
Test an object gravity scale.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Scale to compare to (1 by default)

World gravity on X axis
Compare the world gravity on X axis.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Gravity to compare to (in pixels per second per second)

World gravity on Y axis
Compare the world gravity on Y axis.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Gravity to compare to (in pixels per second per second)

Has fixed rotation
Check if an object has fixed rotation.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is treated as a bullet
Check if the object is being treated as a bullet.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is dynamic
Check if an object is dynamic.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is kinematic
Check if an object is kinematic.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is sleeping
Check if an object is sleeping.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is sleeping allowed
Check if an object can sleep.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Is static
Check if an object is static.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior

Joint first object
Check if an object is the first object on a joint.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Joint reaction force
Test a joint reaction force.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Relational operator
• Parameter 4 (🔢 Number): Value to compare

Joint reaction torque
Test a joint reaction torque.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID
• Parameter 3: 🟰 Relational operator
• Parameter 4 (🔢 Number): Value to compare

Joint second object
Check if an object is the second object on a joint.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Layer enabled
Check if an object has a specific layer enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Layer (1 - 16)

Linear damping
Test an object linear damping.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Value to compare

Linear velocity
Test an object linear velocity length.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Speed to compare to (in pixels per second)

Linear velocity X
Test an object linear velocity on X.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Speed to compare to (in pixels per second)

Linear velocity Y
Test an object linear velocity on Y.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Speed to compare to (in pixels per second)

Mask enabled
Check if an object has a specific mask enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Mask (1 - 16)

Linear velocity angle
Compare the linear velocity angle of the object.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Angle (in degrees)
• Parameter 3 (🔢 Number): Tolerance (in degrees)

Prismatic joint limits enabled
Check if a prismatic joint limits are enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Prismatic joint motor enabled
Check if a prismatic joint motor is enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Restitution
Test an object restitution.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Value to compare

Revolute joint limits enabled
Check if a revolute joint limits are enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Revolute joint motor enabled
Check if a revolute joint motor is enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

World time scale
Compare the world time scale.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2: 🟰 Relational operator
• Parameter 3 (🔢 Number): Time scale to compare to (1 by default)

Wheel joint motor enabled
Check if a wheel joint motor is enabled.

See parameters

• Parameter 0: 👾 Object
• Parameter 1: 🧩 Behavior
• Parameter 2 (🔢 Number): Joint ID

Behavior expressions

Expression	Description
Object.Physics2::AngularDamping()	Get the angular damping of an object.
Object.Physics2::AngularVelocity()	Get the angular velocity of an object.
Object.Physics2::Density()	Get the density of an object.
Object.Physics2::DistanceJointDampingRatio(number)	Distance joint damping ratio
	🔢 Number	Joint ID
Object.Physics2::DistanceJointFrequency(number)	Distance joint frequency
	🔢 Number	Joint ID
Object.Physics2::DistanceJointLength(number)	Distance joint length
	🔢 Number	Joint ID
Object.Physics2::Friction()	Get the friction of an object.
Object.Physics2::FrictionJointMaxForce(number)	Friction joint maximum force
	🔢 Number	Joint ID
Object.Physics2::FrictionJointMaxTorque(number)	Friction joint maximum torque
	🔢 Number	Joint ID
Object.Physics2::GearJointFirstJoint(number)	Gear joint first joint
	🔢 Number	Joint ID
Object.Physics2::GearJointRatio(number)	Gear joint ratio
	🔢 Number	Joint ID
Object.Physics2::GearJointSecondJoint(number)	Gear joint second joint
	🔢 Number	Joint ID
Object.Physics2::GravityScale()	Get the gravity scale of an object.
Object.Physics2::GravityX()	World gravity on X axis
Object.Physics2::GravityY()	World gravity on Y axis
Object.Physics2::Inertia()	Return the rotational inertia of the object (in kilograms · meters²)
Object.Physics2::JointFirstAnchorX(number)	Joint first anchor X
	🔢 Number	Joint ID
Object.Physics2::JointFirstAnchorY(number)	Joint first anchor Y
	🔢 Number	Joint ID
Object.Physics2::JointReactionForce(number)	Joint reaction force
	🔢 Number	Joint ID
Object.Physics2::JointReactionTorque(number)	Joint reaction torque
	🔢 Number	Joint ID
Object.Physics2::JointSecondAnchorX(number)	Joint second anchor X
	🔢 Number	Joint ID
Object.Physics2::JointSecondAnchorY(number)	Joint second anchor Y
	🔢 Number	Joint ID
Object.Physics2::LinearDamping()	Get the linear damping of an object.
Object.Physics2::LinearVelocity()	Get the linear velocity of an object.
Object.Physics2::LinearVelocityAngle()	Get the linear velocity angle of an object.
Object.Physics2::LinearVelocityX()	Get the linear velocity of an object on X axis.
Object.Physics2::LinearVelocityY()	Get the linear velocity of an object on Y axis.
Object.Physics2::Mass()	Return the mass of the object (in kilograms)
Object.Physics2::MassCenterX()	Mass center X
Object.Physics2::MassCenterY()	Mass center Y
Object.Physics2::MotorJointAngularOffset(number)	Motor joint angular offset
	🔢 Number	Joint ID
Object.Physics2::MotorJointCorrectionFactor(number)	Motor joint correction factor
	🔢 Number	Joint ID
Object.Physics2::MotorJointMaxForce(number)	Motor joint maximum force
	🔢 Number	Joint ID
Object.Physics2::MotorJointMaxTorque(number)	Motor joint maximum torque
	🔢 Number	Joint ID
Object.Physics2::MotorJointOffsetX(number)	Motor joint offset X
	🔢 Number	Joint ID
Object.Physics2::MotorJointOffsetY(number)	Motor joint offset Y
	🔢 Number	Joint ID
Object.Physics2::MouseJointDampingRatio(number)	Mouse joint damping ratio
	🔢 Number	Joint ID
Object.Physics2::MouseJointFrequency(number)	Mouse joint frequency
	🔢 Number	Joint ID
Object.Physics2::MouseJointMaxForce(number)	Mouse joint maximum force
	🔢 Number	Joint ID
Object.Physics2::MouseJointTargetX(number)	Mouse joint target X
	🔢 Number	Joint ID
Object.Physics2::MouseJointTargetY(number)	Mouse joint target Y
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointAxisAngle(number)	Prismatic joint axis angle
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointMaxMotorForce(number)	Prismatic joint maximum motor force
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointMaxTranslation(number)	Prismatic joint maximum translation
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointMinTranslation(number)	Prismatic joint minimum translation
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointMotorForce(number)	Prismatic joint motor force
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointMotorSpeed(number)	Prismatic joint motor speed
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointReferenceAngle(number)	Prismatic joint reference angle
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointSpeed(number)	Prismatic joint speed
	🔢 Number	Joint ID
Object.Physics2::PrismaticJointTranslation(number)	Prismatic joint current translation
	🔢 Number	Joint ID
Object.Physics2::PulleyJointFirstGroundAnchorX(number)	Pulley joint first ground anchor X
	🔢 Number	Joint ID
Object.Physics2::PulleyJointFirstGroundAnchorY(number)	Pulley joint first ground anchor Y
	🔢 Number	Joint ID
Object.Physics2::PulleyJointFirstLength(number)	Pulley joint first length
	🔢 Number	Joint ID
Object.Physics2::PulleyJointRatio(number)	Pulley joint ratio
	🔢 Number	Joint ID
Object.Physics2::PulleyJointSecondGroundAnchorX(number)	Pulley joint second ground anchor X
	🔢 Number	Joint ID
Object.Physics2::PulleyJointSecondGroundAnchorY(number)	Pulley joint second ground anchor Y
	🔢 Number	Joint ID
Object.Physics2::PulleyJointSecondLength(number)	Pulley joint second length
	🔢 Number	Joint ID
Object.Physics2::Restitution()	Get the restitution of an object.
Object.Physics2::RevoluteJointAngle(number)	Revolute joint current angle
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointMaxAngle(number)	Revolute joint maximum angle
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointMaxMotorTorque(number)	Revolute joint maximum motor torque
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointMinAngle(number)	Revolute joint minimum angle
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointMotorSpeed(number)	Revolute joint motor speed
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointMotorTorque(number)	Revolute joint motor torque
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointReferenceAngle(number)	Revolute joint reference angle
	🔢 Number	Joint ID
Object.Physics2::RevoluteJointSpeed(number)	Revolute joint angular speed
	🔢 Number	Joint ID
Object.Physics2::RopeJointMaxLength(number)	Rope joint maximum length
	🔢 Number	Joint ID
Object.Physics2::TimeScale()	World time scale
Object.Physics2::WeldJointDampingRatio(number)	Weld joint damping ratio
	🔢 Number	Joint ID
Object.Physics2::WeldJointFrequency(number)	Weld joint frequency
	🔢 Number	Joint ID
Object.Physics2::WeldJointReferenceAngle(number)	Weld joint reference angle
	🔢 Number	Joint ID
Object.Physics2::WheelJointAxisAngle(number)	Wheel joint axis angle
	🔢 Number	Joint ID
Object.Physics2::WheelJointDampingRatio(number)	Wheel joint damping ratio
	🔢 Number	Joint ID
Object.Physics2::WheelJointFrequency(number)	Wheel joint frequency
	🔢 Number	Joint ID
Object.Physics2::WheelJointMaxMotorTorque(number)	Wheel joint maximum motor torque
	🔢 Number	Joint ID
Object.Physics2::WheelJointMotorSpeed(number)	Wheel joint motor speed
	🔢 Number	Joint ID
Object.Physics2::WheelJointMotorTorque(number)	Wheel joint motor torque
	🔢 Number	Joint ID
Object.Physics2::WheelJointSpeed(number)	Wheel joint speed
	🔢 Number	Joint ID
Object.Physics2::WheelJointTranslation(number)	Wheel joint current translation
	🔢 Number	Joint ID
Object.Physics2::WorldScale()	Return the world scale.

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The 2D Physics Engine extension is always installed in all GDevelop projects: there is no need to add it from the Project Manager.

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