120: prototype of futures for buffer mapping r=grovesNL a=swiftcoder
This is largely in request-for-comment state right now, although it does work.
As written the `GpuFuture` implementation only works with types that are `Copy`, which rules out using a destructor to unmap the buffer. I'm assume it's possible to write a future type that can produce a non-Copy result, but I haven't sufficiently internalised how `Pin` works to see how.
Co-authored-by: Tristam MacDonald <swiftcoder@gmail.com>