Crevice creates GLSL-compatible versions of types through the power of derive
macros. Generated structures provide an as_bytes
method to allow safely packing data into buffers for uploading.
Generated structs also implement bytemuck::Zeroable
and
bytemuck::Pod
for use with other libraries.
Crevice is similar to glsl-layout
, but supports types from many
math crates, can generate GLSL source from structs, and explicitly initializes
padding to remove one source of undefined behavior.
Crevice has support for many Rust math libraries via feature flags, and most other math libraries by use of the mint crate. Crevice currently supports:
- mint 0.5, enabled by default
- cgmath 0.18, using the
cgmath
feature - nalgebra 0.31, using the
nalgebra
feature - glam 0.23, using the
glam
feature
PRs are welcome to add or update math libraries to Crevice.
If your math library is not supported, it's possible to define structs using the types from mint and convert your math library's types into mint types. This is supported by most Rust math libraries.
Your math library may require you to turn on a feature flag to get mint support. For example, cgmath requires the "mint" feature to be enabled to allow conversions to and from mint types.
Uploading many types can be done by deriving AsStd140
and
using as_std140
and
as_bytes
to turn the result into bytes.
uniform MAIN {
mat3 orientation;
vec3 position;
float scale;
} main;
use crevice::std140::AsStd140;
#[derive(AsStd140)]
struct MainUniform {
orientation: mint::ColumnMatrix3<f32>,
position: mint::Point3<f32>,
scale: f32,
}
let value = MainUniform {
orientation: [
[1.0, 0.0, 0.0],
[0.0, 1.0, 0.0],
[0.0, 0.0, 1.0],
].into(),
position: [1.0, 2.0, 3.0].into(),
scale: 4.0,
};
let value_std140 = value.as_std140();
upload_data_to_gpu(value_std140.as_bytes());
More complicated data can be uploaded using the std140
Writer
type.
struct PointLight {
vec3 position;
vec3 color;
float brightness;
};
buffer POINT_LIGHTS {
uint len;
PointLight[] lights;
} point_lights;
use crevice::std140::{self, AsStd140};
#[derive(AsStd140)]
struct PointLight {
position: mint::Point3<f32>,
color: mint::Vector3<f32>,
brightness: f32,
}
let lights = vec![
PointLight {
position: [0.0, 1.0, 0.0].into(),
color: [1.0, 0.0, 0.0].into(),
brightness: 0.6,
},
PointLight {
position: [0.0, 4.0, 3.0].into(),
color: [1.0, 1.0, 1.0].into(),
brightness: 1.0,
},
];
let target_buffer = map_gpu_buffer_for_write();
let mut writer = std140::Writer::new(target_buffer);
let light_count = lights.len() as u32;
writer.write(&light_count)?;
// Crevice will automatically insert the required padding to align the
// PointLight structure correctly. In this case, there will be 12 bytes of
// padding between the length field and the light list.
writer.write(lights.as_slice())?;
unmap_gpu_buffer();
std
(default): Enablesstd::io::Write
-based structs.cgmath
: Enables support for types from cgmath.nalgebra
: Enables support for types from nalgebra.glam
: Enables support for types from glam.
Crevice supports Rust 1.74.0 and newer.
Licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.