---
title: vertexDescriptor
framework: modelio
role: symbol
role_heading: Instance Property
path: modelio/mdlasset/vertexdescriptor
---

# vertexDescriptor

The description of the vertex data format to be used for loading mesh data from the asset.

## Declaration

```swift
var vertexDescriptor: MDLVertexDescriptor? { get }
```

## Discussion

Discussion If you specify a vertex descriptor when loading an asset with the init(url:vertexDescriptor:bufferAllocator:) initializer, Model I/O  automatically translates mesh vertex data loaded from the asset into the format described by that MDLVertexDescriptor object. If you do not specify a vertex descriptor, or import an asset through other means, this property’s value is nil, and Model I/O  loads vertex data in whatever format is stored in the asset file.

## See Also

### Working with Asset Content

- [object(at:)](modelio/mdlasset/object(at:).md)
- [subscript(_:)](modelio/mdlasset/subscript(_:).md)
- [count](modelio/mdlasset/count.md)
- [childObjects(of:)](modelio/mdlasset/childobjects(of:).md)
- [add(_:)](modelio/mdlasset/add(_:).md)
- [remove(_:)](modelio/mdlasset/remove(_:).md)
- [boundingBox](modelio/mdlasset/boundingbox.md)
- [boundingBox(atTime:)](modelio/mdlasset/boundingbox(attime:).md)
- [url](modelio/mdlasset/url.md)
- [bufferAllocator](modelio/mdlasset/bufferallocator.md)
- [masters](modelio/mdlasset/masters.md)