---
title: "init(shape:mass:)"
framework: realitykit
role: symbol
role_heading: Initializer
path: "realitykit/physicsmassproperties/init(shape:mass:)"
---

# init(shape:mass:)

Creates the mass properties for a solid shape with the specified mass.

## Declaration

```swift
@MainActor @preconcurrency init(shape: ShapeResource, mass: Float)
```

## Parameters

- `shape`: The shape for which to calculate the mass frame.
- `mass`: The mass of the object in kilograms.

## See Also

### Creating custom mass properties

- [init()](realitykit/physicsmassproperties/init().md)
- [init(mass:inertia:centerOfMass:)](realitykit/physicsmassproperties/init(mass:inertia:centerofmass:).md)
- [init(shape:density:)](realitykit/physicsmassproperties/init(shape:density:).md)