Rigid Body
Updated: 4 Dec 2023
Generates a static or dynamic rigid body collision object.
Rigid Body
Method #
The Rigid Body node defines a static or dynamic rigid body collision object. This is a 3D body that moves under physics and collides with other objects in the same physics system - under the same Rigid Body Root. It must be parented to a Rigid Body Root for physics to work. Useful for quickly setting up collision surfaces, such as side barriers or angled ground planes.
Parameters
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
Parameter Details Position X The objects position along the local x-axis.
Position Y The objects position along the local y-axis.
Position Z The objects position along the local z-axis.
Rotation Heading The objects rotation around the local y-axis.
Rotation Pitch The objects rotation around the local x-axis.
Rotation Bank The objects rotation around the local z-axis.
Scale X The objects scale along the local x-axis.
Scale Y The objects scale along the local y-axis.
Scale Z The objects scale along the local z-axis.
Control the inheritance of the transforms from the parent.
Parameter Details Position Toggle inheritance of the Position from the parent.
Rotation Toggle inheritance of the Rotation from the parent.
Scale Toggle inheritance of the Scale from the parent.
World Position Only Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties.
Inherit Time Toggle inheritance of time from the parent.
These properties control the core behaviours of the node.
Parameter Details Dynamics Mode How the object is used in a physics simulation.
- Static : A static rigid body does not move and can’t be moved by physics, but will act as a collider for other dynamic objects. An example could be a floor or wall.
- Kinematic : A kinematic rigid body is not moved by physics but has a velocity that can affect dynamic bodies. An example could be a moving platform or rotating collider.
- Dynamic : A dynamic rigid body has its initial position set by its transform, but transform control is taken over by physics as soon as the simulation starts.
- Disabled : Physics will not be applied, and the object will be ignored for simulation.
Dynamics Transform For Rendering Only (Faster) If selected, the transform of the body is maintained on GPU only. This reduces latency and increases performance but means that parenting to the object, e.g. using it to transform lights will not work.
Rigid Body Shape The shape of the rigid body used for physics simulation. Often times, a simpler approximation of a mesh can be used for significantly improved performance.
- Sphere : A sphere, useful for emulating balls or roundish objects.
- Box : A box, useful for emulating boxy objects.
- Plane : A flat infinite plane, useful for setting up solid walls. May only be static or kinematic.
- 3D Object (Convex Hull) : A convex hull derived from the geometry of the node, with its own modes to set the convex hull generation below.
- 3D Object (Use Original Geometry) : The original triangle geometry of the node, if applicable. Best used with low poly meshes.
Rigid Body Sphere Radius The radius of the rigid body if Sphere is selected in the Rigid Body Shape.
Rigid Body Box Size X The width of the rigid body shape if Box is selected in the Rigid Body Shape.
Rigid Body Box Size Y The height of the rigid body box shape if Box is selected in the Rigid Body Shape.
Rigid Body Box Size Z The depth of the rigid body box shape if Box is selected in the Rigid Body Shape.
Rigid Body Convex Hull Mode Determines the convex hull shape generation used to wrap around the node’s geometry. only functions if the Convex Hull shape is selected in the Rigid Body Shape.
- 10 Faces (Cylinder) X-Axis : A simplified cylinder with 10 sides pointing along the X axis.
- 10 Faces (Cylinder) Y-Axis : A simplified cylinder with 10 sides pointing along the Y axis.
- 10 Faces (Cylinder) Z-Axis : A simplified cylinder with 10 sides pointing along the Z axis.
- 14 Faces (Capsule) - X-Axis : A simplified capsule with 10 sides pointing along the X axis.
- 14 Faces (Capsule) - Y-Axis : A simplified capsule with 10 sides pointing along the Y axis.
- 14 Faces (Capsule) - Z-Axis : A simplified capsule with 10 sides pointing along the Z axis.
- 18 Faces (Rounded Box) : A simplified beveled box with 18 sides.
Bake Physics Transforms Bake the physics transforms so they are no longer simulated per frame, and simply animated back.
Baked Transform The baked transforms, useful for adjusting the animation after baking.
Show Rigid Body Displays a debug view of the actual rigid body shapes being used to calculate collisions.
These properties control the physical properties of the rigid bodies, changing how each object interacts with one another.
Parameter Details Friction How much other rigid bodies will be able to slide along side this rigid body. When two rigid bodies of different frictions interact, the minimum value is used.
Bounciness How much this rigid body will bounce off of other rigid bodies in the scene.
Density The density of the rigid body. The density is scaled by the area of the shape to determine the mass of the body.
Spin X The spin of the rigid body on the X axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied.
Spin Y The spin of the rigid body on the Y axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied.
Spin Z The spin of the rigid body on the Z axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied.
Inputs
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
| Parameter | Details |
|---|---|
| Position X | The objects position along the local x-axis. |
| Position Y | The objects position along the local y-axis. |
| Position Z | The objects position along the local z-axis. |
| Rotation Heading | The objects rotation around the local y-axis. |
| Rotation Pitch | The objects rotation around the local x-axis. |
| Rotation Bank | The objects rotation around the local z-axis. |
| Scale X | The objects scale along the local x-axis. |
| Scale Y | The objects scale along the local y-axis. |
| Scale Z | The objects scale along the local z-axis. |
Control the inheritance of the transforms from the parent.
| Parameter | Details |
|---|---|
| Position | Toggle inheritance of the Position from the parent. |
| Rotation | Toggle inheritance of the Rotation from the parent. |
| Scale | Toggle inheritance of the Scale from the parent. |
| World Position Only | Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties. |
| Inherit Time | Toggle inheritance of time from the parent. |
These properties control the core behaviours of the node.
| Parameter | Details |
|---|---|
| Dynamics Mode | How the object is used in a physics simulation.
|
| Dynamics Transform For Rendering Only (Faster) | If selected, the transform of the body is maintained on GPU only. This reduces latency and increases performance but means that parenting to the object, e.g. using it to transform lights will not work. |
| Rigid Body Shape | The shape of the rigid body used for physics simulation. Often times, a simpler approximation of a mesh can be used for significantly improved performance.
|
| Rigid Body Sphere Radius | The radius of the rigid body if Sphere is selected in the Rigid Body Shape. |
| Rigid Body Box Size X | The width of the rigid body shape if Box is selected in the Rigid Body Shape. |
| Rigid Body Box Size Y | The height of the rigid body box shape if Box is selected in the Rigid Body Shape. |
| Rigid Body Box Size Z | The depth of the rigid body box shape if Box is selected in the Rigid Body Shape. |
| Rigid Body Convex Hull Mode | Determines the convex hull shape generation used to wrap around the node’s geometry. only functions if the Convex Hull shape is selected in the Rigid Body Shape.
|
| Bake Physics Transforms | Bake the physics transforms so they are no longer simulated per frame, and simply animated back. |
| Baked Transform | The baked transforms, useful for adjusting the animation after baking. |
| Show Rigid Body | Displays a debug view of the actual rigid body shapes being used to calculate collisions. |
These properties control the physical properties of the rigid bodies, changing how each object interacts with one another.
| Parameter | Details |
|---|---|
| Friction | How much other rigid bodies will be able to slide along side this rigid body. When two rigid bodies of different frictions interact, the minimum value is used. |
| Bounciness | How much this rigid body will bounce off of other rigid bodies in the scene. |
| Density | The density of the rigid body. The density is scaled by the area of the shape to determine the mass of the body. |
| Spin X | The spin of the rigid body on the X axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied. |
| Spin Y | The spin of the rigid body on the Y axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied. |
| Spin Z | The spin of the rigid body on the Z axes. This scales the inertia tensor on this axes, making the body spin faster or slower in that direction when torque is applied. |
| Name | Description | Typical Input |
|---|---|---|
| Object Node | Allows a 3D Object node to be connected to define the shape of the body. | 3D Object |
| Transform Modifiers | Apply the transforms of another node to this node. | Null |
| Target Node | Modifiy the rotations of the node to always direct the z axis towards the input. | Null |
| Local Transform Override | Apply the transforms of another node to this node, relative to its parent. | Null |