Crash when keyboard is shown

[Frederik Riedel]

Hello!

First of all, thanks a lot for creating this wonderful library.

I am planning to use it in one of my apps, but I stumbled across a crash when the iOS keyboard is shown.

I am able to reproduce this 100% of times, happy to provide more data if you need.

This is the crash:

-[MTLTextureDescriptorInternal validateWithDevice:], line 1357: error 'Texture Descriptor Validation
MTLTextureDescriptor has height of zero.
'

this is the LOC that is causing the problem in MTLComputeNoiseFunction.swift:

guard let noiseTexture = device.**makeTexture**(descriptor: textureDescriptor),
              let encoder = commandBuffer.makeComputeCommandEncoder()

Let me know if you need any more information!