---
title: MTLTessellationFactorStepFunction.perPatchAndPerInstance
framework: metal
role: symbol
role_heading: Case
path: metal/mtltessellationfactorstepfunction/perpatchandperinstance
---

# MTLTessellationFactorStepFunction.perPatchAndPerInstance

A per-patch and per-instance step function. For a given instance ID, the tessellation factor for a patch in a patch draw call is at the offset + (drawPatchIndex * tessellationFactorStride + instanceID * instanceStride) location in the tessellation factor buffer.

## Declaration

```swift
case perPatchAndPerInstance
```

## See Also

### Factor step functions

- [MTLTessellationFactorStepFunction.constant](metal/mtltessellationfactorstepfunction/constant.md)
- [MTLTessellationFactorStepFunction.perPatch](metal/mtltessellationfactorstepfunction/perpatch.md)
- [MTLTessellationFactorStepFunction.perInstance](metal/mtltessellationfactorstepfunction/perinstance.md)