Update the readme to reflect the project status as of 2022-august

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Lokathor 2022-08-14 09:52:26 -06:00
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* **[Latest Docs.rs Here](https://docs.rs/bytemuck/)**
[![License:Zlib](https://img.shields.io/badge/License-Zlib-brightgreen.svg)](https://opensource.org/licenses/Zlib)
![Minimum Rust Version](https://img.shields.io/badge/Min%20Rust-1.34-green.svg)
[![crates.io](https://img.shields.io/crates/v/bytemuck.svg)](https://crates.io/crates/bytemuck)
[![docs.rs](https://docs.rs/bytemuck/badge.svg)](https://docs.rs/bytemuck/)
# bytemuck
A crate for mucking around with piles of bytes.
This crate lets you safely perform "bit cast" operations between data types.
That's where you take a value and just reinterpret the bits as being some other
type of value, without changing the bits.
* This is **not** like the [`as` keyword][keyword-as]
* This is **not** like the [`From` trait][from-trait]
* It is **most like** [`f32::to_bits`][f32-to_bits], just generalized to let you
convert between all sorts of data types.
[keyword-as]: https://doc.rust-lang.org/nightly/std/keyword.as.html
[from-trait]: https://doc.rust-lang.org/nightly/core/convert/trait.From.html
[f32-to_bits]: https://doc.rust-lang.org/nightly/std/primitive.f32.html#method.to_bits
### Here's the part you're more likely to care about: *you can do this with slices too!*
When a slice is involved it's not a *direct* bitcast. Instead, the `cast_slice`
and `cast_slice_mut` functions will pull apart a slice's data and give you a new
slice that's the same span of memory just viewed as the new type. If the size of
the slice's element changes then the length of the slice you get back will be
changed accordingly.
This lets you cast a slice of color values into a slice of `u8` and send it to
the GPU, or things like that. I'm sure there's other examples, but honestly this
crate is as popular as it is mostly because of Rust's 3D graphics community
wanting to cast slices of different types into byte slices for sending to the
GPU. Hi friends! Push those vertices, or whatever it is that you all do.
## See Also
While `bytemuck` is full of unsafe code, I've also started a "sibling crate"
called [bitfrob](https://docs.rs/bitfrob/latest/bitfrob/), which is where
operations that are 100% safe will be added.
## Stability
The goal is to stay at 1.y.z until _at least_ the next edition of Rust.
* The crate is 1.0 and I consider this it to be "basically done". New features
are usually being accepted when other people want to put in the work, but
myself I wanna move on to using `bytemuck` in bigger projects.
* The core of the `bytemuck` crate will continue to work with `rustc-1.34` for
at least the rest of the `1.y.z` versions.
* Opt-in features of the crate *are not* held to the same standard, and may work
only on the latest Stable or latest Nightly.
I consider any increase of the Minimum Rust Version to be a semver breaking change,
so `rustc-1.34` will continue to be supported for at least the rest of the
`bytemuck-1.y.z` series of the crate.
**Future Plans:** Once the [Safe Transmute Project][pg-st] completes and
stabilizes ("eventually") this crate will be updated to use that as the
underlying mechanism for transmutation bounds, and a 2.0 version of `bytemuck`
will be released. The hope is for the 1.0 to 2.0 transition to be as seamless as
possible, but the future is always uncertain.
(The secret goal is to get all of this functionality into the standard library
some day so that we don't even need to import a crate to do all this fun stuff.)
[pg-st]: https://rust-lang.github.io/rfcs/2835-project-safe-transmute.html