---
title: motionStartTime
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtlprimitiveaccelerationstructuredescriptor/motionstarttime
---

# motionStartTime

The start time for the range of motion that the keyframe data describes.

## Declaration

```swift
var motionStartTime: Float { get set }
```

## Discussion

Discussion The default value is 0.0f.

## See Also

### Specifying motion behavior

- [motionKeyframeCount](metal/mtlprimitiveaccelerationstructuredescriptor/motionkeyframecount.md)
- [motionEndTime](metal/mtlprimitiveaccelerationstructuredescriptor/motionendtime.md)
- [motionStartBorderMode](metal/mtlprimitiveaccelerationstructuredescriptor/motionstartbordermode.md)
- [motionEndBorderMode](metal/mtlprimitiveaccelerationstructuredescriptor/motionendbordermode.md)
- [MTLMotionBorderMode](metal/mtlmotionbordermode.md)