---
title: "formInset(by:)"
framework: spatial
role: symbol
role_heading: Instance Method
path: "spatial/rect3d/forminset(by:)"
---

# formInset(by:)

Insets the rectangle by the specified size.

## Declaration

```swift
mutating func formInset(by dXYZ: Size3D)
```

## Parameters

- `dXYZ`: The size structure that defines the inset values.

## See Also

### Creating derived 3D rectangles

- [integral](spatial/rect3d/integral.md)
- [inset(by:)](spatial/rect3d/inset(by:).md)
- [intersection(_:)](spatial/rect3d/intersection(_:).md)
- [standardized](spatial/rect3d/standardized.md)