---
title: "length(_:ofSegment:ofPath:at:)"
framework: Professional Video Applications
role: symbol
role_heading: Instance Method
platforms: [fxplug 4.0+]
path: "professional_video_applications/fxpathapi_v3/length(_:ofsegment:ofpath:at:)"
---

# length(_:ofSegment:ofPath:at:)

Provides the length of one segment of the entire path.

## Declaration

```swift
func length(_ length: UnsafeMutablePointer<Double>!, ofSegment segmentIndex: Int, ofPath pathID: FxPathID!, at time: CMTime) throws
```

## Parameters

- `length`: Upon return, contains the length (in pixels) of the desired segment.
- `segmentIndex`: Which segment of the path you wish to evaluate the length of.
- `pathID`: The ID of the path whose segment you wish to evaluate.
- `time`: The time at which to evaluate the length of a segment of a path.

## See Also

### Getting Path Information

- [numberOfPaths(at:)](professional_video_applications/fxpathapi_v3/numberofpaths(at:).md)
- [pathID(_:for:)](professional_video_applications/fxpathapi_v3/pathid(_:for:).md)
- [name(_:ofPath:)](professional_video_applications/fxpathapi_v3/name(_:ofpath:).md)
- [isPath(_:open:at:)](professional_video_applications/fxpathapi_v3/ispath(_:open:at:).md)
- [isPath(_:inverted:at:)](professional_video_applications/fxpathapi_v3/ispath(_:inverted:at:).md)
- [style(_:ofPath:)](professional_video_applications/fxpathapi_v3/style(_:ofpath:).md)
- [length(_:ofPath:at:)](professional_video_applications/fxpathapi_v3/length(_:ofpath:at:).md)
- [number(ofVertices:inPath:at:)](professional_video_applications/fxpathapi_v3/number(ofvertices:inpath:at:).md)
- [vertex(_:at:ofPath:at:)](professional_video_applications/fxpathapi_v3/vertex(_:at:ofpath:at:).md)
- [point(_:atPercentageOfDistance:alongPath:at:)](professional_video_applications/fxpathapi_v3/point(_:atpercentageofdistance:alongpath:at:).md)
- [point(_:atPercentageOfParameter:alongPath:at:)](professional_video_applications/fxpathapi_v3/point(_:atpercentageofparameter:alongpath:at:).md)
- [blendMode(_:ofPath:)](professional_video_applications/fxpathapi_v3/blendmode(_:ofpath:).md)
- [pathGeometryInfo(_:forPath:at:)](professional_video_applications/fxpathapi_v3/pathgeometryinfo(_:forpath:at:).md)