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# PHASEEnvelopeSegment

A curved portion of an envelope.

```
class PHASEEnvelopeSegment
```

## Overview

This class specifies a curve that determines the _y-_value rate of change over a particular portion of an envelope’s graph. For example, the difference between a [`PHASECurveType.cubed`](/documentation/PHASE/PHASECurveType/cubed) segment and an [`PHASECurveType.inverseCubed`](/documentation/PHASE/PHASECurveType/inverseCubed) segment is that they share opposite rates of change; where the cubed curve’s *y* value changes fastest in the segment’s domain, the inverse-cubed curve changes slowest, and vice versa.

## Topics

### Creating a Segment

[`-  initWithEndPoint:curveType:`](/documentation/PHASE/PHASEEnvelopeSegment/init(endPoint:curveType:))

Creates a curved portion of an envelope.

### Shaping a Segment

[`curveType`](/documentation/PHASE/PHASEEnvelopeSegment/curveType)

A curve along the envelope that shapes the segment.

[`endPoint`](/documentation/PHASE/PHASEEnvelopeSegment/endPoint)

A point that identifies the end of the segment along the envelope.

## Relationships

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

### Conforms To

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

[`Equatable`](/documentation/Swift/Equatable)

[`CVarArg`](/documentation/Swift/CVarArg)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

---

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