let targetTexture = currentDrawable?.texture else{ return }

Value of type ‘MTLDrawable’ has no member ‘texture’

好像苹果改变了一些金属api

这是我试用的全部功能：

func renderImage()
{
    guard let
        image = image,let targetTexture = currentDrawable?.texture else{return}

    let commandBuffer = commandQueue.makeCommandBuffer()

    let bounds = CGRect(origin: CGPoint.zero,size: drawableSize)

    let originX = image.extent.origin.x
    let originY = image.extent.origin.y

    let scaleX = drawableSize.width / image.extent.width
    let scaleY = drawableSize.height / image.extent.height
    let scale = min(scaleX,scaleY)

    let scaledImage = image
        .applying(CGAffineTransform(translationX: -originX,y: -originY))
        .applying(CGAffineTransform(scaleX: scale,y: scale))

    ciContext.render(scaledImage,to: targetTexture,commandBuffer: commandBuffer,bounds: bounds,colorSpace: colorSpace)

    commandBuffer.present(currentDrawable!)

    commandBuffer.commit()
}