mirror of
https://github.com/Lokathor/bytemuck.git
synced 2024-11-22 06:42:25 +00:00
61 lines
2.9 KiB
Markdown
61 lines
2.9 KiB
Markdown
* **[Latest Docs.rs Here](https://docs.rs/bytemuck/)**
|
|
|
|
[](https://opensource.org/licenses/Zlib)
|
|
|
|
[](https://crates.io/crates/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 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.
|
|
|
|
**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.
|
|
|
|
[pg-st]: https://rust-lang.github.io/rfcs/2835-project-safe-transmute.html
|