---
title: "handleBinding(ofBufferNamed:frequency:handler:)"
framework: scenekit
role: symbol
role_heading: Instance Method
path: "scenekit/scnprogram/handlebinding(ofbuffernamed:frequency:handler:)"
---

# handleBinding(ofBufferNamed:frequency:handler:)

Registers a block for SceneKit to call at render time for binding a Metal buffer to the shader program.

## Declaration

```swift
func handleBinding(ofBufferNamed name: String, frequency: SCNBufferFrequency, handler block: @escaping SCNBufferBindingBlock)
```

## Parameters

- `name`: The name identifying the buffer in Metal shader source code.
- `frequency`: An option specifying whether SceneKit calls the block only once per rendered frame or more frequently (for example, once for each object to be rendered).
- `block`: A block to be run when SceneKit prepares for rendering with the Metal shader.

## Discussion

Discussion Use this method to associate a block with a Metal shader program to handle setup of a buffer used in that shader. SceneKit calls your block before rendering any objects whose program property is set to this SCNProgram object. In the block, use the writeBytes(_:count:) method to provide data for the buffer.

## See Also

### Providing Input for Metal Shaders

- [SCNBufferFrequency](scenekit/scnbufferfrequency.md)
- [SCNBufferBindingBlock](scenekit/scnbufferbindingblock.md)