bevy/crates/bevy_mikktspace/src/lib.rs
Tristan Guichaoua c1a4e29a1e
Replace pointer castings (as) by their API equivalent (#11818)
# Objective

Since rust `1.76`,
[`ptr::from_ref`](https://doc.rust-lang.org/stable/std/ptr/fn.from_ref.html)
and
[`ptr::from_mut`](https://doc.rust-lang.org/stable/std/ptr/fn.from_mut.html)
are stable.

This PR replaces code that use `as` casting by one of `ptr::from_ref`,
`ptr::from_mut`, `cast_mut`, `cast_const`, or `cast` methods, which are
less error-prone.

## Solution

- Bump MSRV to `1.76.0`
- Enables the following clippy lints:
-
[`ptr_as_ptr`](https://rust-lang.github.io/rust-clippy/master/index.html#/ptr_as_ptr)
-
[`ptr_cast_constness`](https://rust-lang.github.io/rust-clippy/master/index.html#/ptr_cast_constness)
-
[`ref_as_ptr`](https://rust-lang.github.io/rust-clippy/master/index.html#/ref_as_ptr)
(I fix all warnings for this one, but it requires rust 1.77 to be
enabled)
- Fix the lints mentioned above
2024-02-11 23:19:36 +00:00

93 lines
2.9 KiB
Rust

#![allow(
unsafe_op_in_unsafe_fn,
clippy::all,
clippy::undocumented_unsafe_blocks,
clippy::ptr_cast_constness
)]
// FIXME(3492): remove once docs are ready
#![allow(missing_docs)]
use glam::{Vec2, Vec3};
mod generated;
/// The interface by which mikktspace interacts with your geometry.
pub trait Geometry {
/// Returns the number of faces.
fn num_faces(&self) -> usize;
/// Returns the number of vertices of a face.
fn num_vertices_of_face(&self, face: usize) -> usize;
/// Returns the position of a vertex.
fn position(&self, face: usize, vert: usize) -> [f32; 3];
/// Returns the normal of a vertex.
fn normal(&self, face: usize, vert: usize) -> [f32; 3];
/// Returns the texture coordinate of a vertex.
fn tex_coord(&self, face: usize, vert: usize) -> [f32; 2];
/// Sets the generated tangent for a vertex.
/// Leave this function unimplemented if you are implementing
/// `set_tangent_encoded`.
fn set_tangent(
&mut self,
tangent: [f32; 3],
_bi_tangent: [f32; 3],
_f_mag_s: f32,
_f_mag_t: f32,
bi_tangent_preserves_orientation: bool,
face: usize,
vert: usize,
) {
let sign = if bi_tangent_preserves_orientation {
1.0
} else {
-1.0
};
self.set_tangent_encoded([tangent[0], tangent[1], tangent[2], sign], face, vert);
}
/// Sets the generated tangent for a vertex with its bi-tangent encoded as the 'W' (4th)
/// component in the tangent. The 'W' component marks if the bi-tangent is flipped. This
/// is called by the default implementation of `set_tangent`; therefore, this function will
/// not be called by the crate unless `set_tangent` is unimplemented.
fn set_tangent_encoded(&mut self, _tangent: [f32; 4], _face: usize, _vert: usize) {}
}
/// Generates tangents for the input geometry.
///
/// # Errors
///
/// Returns `false` if the geometry is unsuitable for tangent generation including,
/// but not limited to, lack of vertices.
pub fn generate_tangents<I: Geometry>(geometry: &mut I) -> bool {
unsafe { generated::genTangSpace(geometry, 180.0) }
}
fn get_position<I: Geometry>(geometry: &mut I, index: usize) -> Vec3 {
let (face, vert) = index_to_face_vert(index);
geometry.position(face, vert).into()
}
fn get_tex_coord<I: Geometry>(geometry: &mut I, index: usize) -> Vec3 {
let (face, vert) = index_to_face_vert(index);
let tex_coord: Vec2 = geometry.tex_coord(face, vert).into();
let val = tex_coord.extend(1.0);
val
}
fn get_normal<I: Geometry>(geometry: &mut I, index: usize) -> Vec3 {
let (face, vert) = index_to_face_vert(index);
geometry.normal(face, vert).into()
}
fn index_to_face_vert(index: usize) -> (usize, usize) {
(index >> 2, index & 0x3)
}
fn face_vert_to_index(face: usize, vert: usize) -> usize {
face << 2 | vert & 0x3
}