---
title: ARGeoAnchor.AltitudeSource.userDefined
framework: arkit
role: symbol
role_heading: Case
path: arkit/argeoanchor/altitudesource-swift.enum/userdefined
---

# ARGeoAnchor.AltitudeSource.userDefined

The app defines the altitude.

## Declaration

```swift
case userDefined
```

## Discussion

Discussion ARKit records this altitude source when your app defines a geo anchor’s altitude. You may acquire altitude by providing a particular scene coordinate to the session using getGeoLocation(forPoint:completionHandler:). For example, your app might set a geo anchor’s altitude by raycasting a surface, then adding an arbitrary y-amount to make the anchor more visible from afar.

## See Also

### Sources

- [ARGeoAnchor.AltitudeSource.precise](arkit/argeoanchor/altitudesource-swift.enum/precise.md)
- [ARGeoAnchor.AltitudeSource.coarse](arkit/argeoanchor/altitudesource-swift.enum/coarse.md)
- [ARGeoAnchor.AltitudeSource.unknown](arkit/argeoanchor/altitudesource-swift.enum/unknown.md)