---
title: "CATransform3DConcat(_:_:)"
framework: Core Animation
role: symbol
role_heading: Function
platforms: [iOS 2.0+, iPadOS 2.0+, Mac Catalyst 13.1+, macOS 10.5+, tvOS 9.0+, visionOS 1.0+]
path: "quartzcore/catransform3dconcat(_:_:)"
---

# CATransform3DConcat(_:_:)

Concatenates b to a and returns the result: t = a * b.

## Declaration

```swift
func CATransform3DConcat(_ a: CATransform3D, _ b: CATransform3D) -> CATransform3D
```

## See Also

### Chaining Transforms

- [CATransform3DTranslate(_:_:_:_:)](quartzcore/catransform3dtranslate(_:_:_:_:).md)
- [CATransform3DScale(_:_:_:_:)](quartzcore/catransform3dscale(_:_:_:_:).md)
- [CATransform3DRotate(_:_:_:_:_:)](quartzcore/catransform3drotate(_:_:_:_:_:).md)