internal/graphicsdriver/metal/ca/ca.go
func (ml MetalLayer) NextDrawable() (MetalDrawable, error) {
	md := C.MetalLayer_NextDrawable(ml.metalLayer)
	if md == nil {
		return MetalDrawable{}, errors.New("nextDrawable returned nil")
	}

	return MetalDrawable{md}, nil
}
func (ml MetalLayer) NextDrawable() (MetalDrawable, error) {
	md := C.MetalLayer_NextDrawable(ml.metalLayer)
	if md == nil {
		return MetalDrawable{}, errors.New("nextDrawable returned nil")
	}

	return MetalDrawable{md}, nil
}
// NextDrawable returns a Metal drawable.
//
// Reference: https://developer.apple.com/documentation/quartzcore/cametallayer/1478172-nextdrawable.