---
title: "init(horizontal:vertical:)"
framework: metal
role: symbol
role_heading: Initializer
path: "metal/mtlrasterizationratelayerdescriptor/init(horizontal:vertical:)"
---

# init(horizontal:vertical:)

Initializes a layer rate map with a set of horizontal and vertical rasterization rates.

## Declaration

```swift
convenience init(horizontal: [Float], vertical: [Float])
```

## Parameters

- `horizontal`: An array of the horizontal rates to apply across the grid.
- `vertical`: An array of the vertical rates to apply across the grid.

## Return Value

Return Value A layer descriptor whose width is the number of horizontal rates and whose height is the number of vertical rates. The layer descriptor copies the values from the input parameters.

## See Also

### Creating a layer rasterization rate descriptor

- [init(sampleCount:)](metal/mtlrasterizationratelayerdescriptor/init(samplecount:).md)