运行报错

[GeneralJing]

    let positions = unsafeBitCast(positionsIn!.contents(), to: UnsafeMutablePointer<Float>.self)
    let _velocities = unsafeBitCast(velocities!.contents(), to: UnsafeMutablePointer<Float>.self)

这个是报错的位置，提示的错误信息如下：
Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value
不太熟悉swift、metal，能告诉这个是什么问题吗？

[roberthein]

Really @GeneralJing ? Chinese?
I'll have a look 😉

[GeneralJing]

reply so quickly,thank you

[GeneralJing]

Do you know what caused this reason?I'm not familiar with swift and metal. Do you have some demos using oc and opengles?

[dfmarulanda]

Did you fixed it?

[dfmarulanda]

Seems to be a problem with the simulator

[roberthein]

I'm sorry but can't find the time to investigate/fix this right now. But will look at PR's if you can find the time to look at it.