Collisions
Reference
- Panel
- Shape
Determines the collision shape of the object; these can be broken into two categories: primitive shapes and mesh based shapes.
Primitive shapes (Box, Sphere, Capsule, Cylinder, and Cone) are best in terms of memory and performance but do not necessarily reflect the actual shape of the object. They are calculated based on the object's bounding box. The center of gravity is always in the geometric center of the shape. Primitive shapes can be shown in the 3D Viewport by enabling Bounds.
Mesh based shapes (Convex Hull and Mesh) are calculated based on the geometry of the object so they are a better representation of the object. The center of gravity for these shapes is the object origin.
- Box
Box-like shapes (e.g. cubes), including planes (e.g. ground planes). The size per axis is calculated from the bounding box.
- Sphere
Sphere-like shapes. The radius is the largest axis of the bounding box.
- Capsule
This points up the Z axis.
- Cylinder
This points up the Z axis. The height is taken from the Z axis, while the radius is the larger of the X or Y axes.
- Cone
This points up the Z axis. The height is taken from the Z axis, while the radius is the larger of the X or Y axes.
- Convex Hull
A mesh-like surface encompassing (e.g. shrink-wrapped over) all vertices (best results with fewer vertices). A convex approximation of the object, which has good performance and stability.
- Mesh
Mesh consisting of triangles only, allowing for more detailed interactions than convex hulls. Allows simulating concave objects, but is rather slow and unstable.
- Compound Parent
Takes the collision shapes from the object's children and combines them. This makes it possible to create concave shapes from primitive shapes. This usually results in a faster simulation than the Mesh collision shape while also being generally more stable.
- Source
Source of the mesh used to create the collision shape.
- Base
The base mesh of the object.
- Deform
Includes any deformations added to the mesh (shape keys, deform modifiers).
- Deforming
Mesh shapes can deform during simulation.
- Final
Includes all deformations and modifiers.
Surface Response
- Friction
Resistance of object to movement. Specifies how much velocity is lost when objects collide with each other.
- Bounciness
Tendency of object to bounce after colliding with another (0 to 1) (rigid to perfectly elastic). Specifies how much objects can bounce after collisions.
Sensitivity
The collision margin is used to improve the performance and stability of rigid bodies. Depending on the shape, it behaves differently: some shapes embed it, while others have a visible gap around them.
The margin is embedded for these shapes:
Sphere
Box
Capsule
Cylinder
Convex Hull: Only allows for uniform scale when embedded.
The margin is not embedded for these shapes:
Cone
Active Triangle Mesh
Passive Triangle Mesh: Can be set to 0 most of the time.
- Margin
Threshold of distance near the surface where collisions are still considered (best results when nonzero).
Collections
Allows rigid body collisions allocate on different groups (maximum 20).