#![allow(
clippy::bool_assert_comparison,
clippy::useless_conversion,
clippy::redundant_else,
clippy::match_same_arms,
clippy::semicolon_if_nothing_returned,
clippy::explicit_iter_loop,
clippy::map_flatten
)]
use bevy_mikktspace::{generate_tangents, Geometry};
use glam::{Vec2, Vec3};
pub type Face = [u32; 3];
#[derive(Debug)]
struct Vertex {
position: Vec3,
normal: Vec3,
tex_coord: Vec2,
}
#[derive(Debug, PartialEq)]
struct Result {
tangent: [f32; 3],
bi_tangent: [f32; 3],
mag_s: f32,
mag_t: f32,
bi_tangent_preserves_orientation: bool,
face: usize,
vert: usize,
}
impl Result {
fn new(
tangent: [f32; 3],
bi_tangent: [f32; 3],
mag_s: f32,
mag_t: f32,
bi_tangent_preserves_orientation: bool,
face: usize,
vert: usize,
) -> Self {
Self {
tangent,
bi_tangent,
mag_s,
mag_t,
bi_tangent_preserves_orientation,
face,
vert,
}
}
}
struct Mesh {
faces: Vec<Face>,
vertices: Vec<Vertex>,
}
struct Context {
mesh: Mesh,
results: Vec<Result>,
}
fn vertex(mesh: &Mesh, face: usize, vert: usize) -> &Vertex {
let vs: &[u32; 3] = &mesh.faces[face];
&mesh.vertices[vs[vert] as usize]
}
impl Geometry for Context {
fn num_faces(&self) -> usize {
self.mesh.faces.len()
}
fn num_vertices_of_face(&self, _face: usize) -> usize {
3
}
fn position(&self, face: usize, vert: usize) -> [f32; 3] {
vertex(&self.mesh, face, vert).position.into()
}
fn normal(&self, face: usize, vert: usize) -> [f32; 3] {
vertex(&self.mesh, face, vert).normal.into()
}
fn tex_coord(&self, face: usize, vert: usize) -> [f32; 2] {
vertex(&self.mesh, face, vert).tex_coord.into()
}
fn set_tangent(
&mut self,
tangent: [f32; 3],
bi_tangent: [f32; 3],
mag_s: f32,
mag_t: f32,
bi_tangent_preserves_orientation: bool,
face: usize,
vert: usize,
) {
self.results.push(Result {
tangent,
bi_tangent,
mag_s,
mag_t,
bi_tangent_preserves_orientation,
face,
vert,
})
}
}
struct ControlPoint {
uv: [f32; 2],
dir: [f32; 3],
}
impl ControlPoint {
fn new(uv: [f32; 2], dir: [f32; 3]) -> Self {
Self { uv, dir }
}
}
fn make_cube() -> Mesh {
let mut faces = Vec::new();
let mut ctl_pts = Vec::new();
let mut vertices = Vec::new();
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([0.0, 0.0], [1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([1.0, 1.0], [1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([1.0, 0.0], [1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.5, 0.5], [1.0, 0.0, 0.0]));
}
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([1.0, 0.0], [-1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([1.0, 1.0], [-1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [-1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.0], [-1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.5, 0.5], [-1.0, 0.0, 0.0]));
}
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([0.0, 0.0], [1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [-1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.0], [-1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.5], [0.0, 1.0, 0.0]));
}
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([0.0, 0.0], [-1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [-1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.0], [1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.5], [0.0, -1.0, 0.0]));
}
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([0.0, 0.0], [-1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [-1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([1.0, 1.0], [1.0, -1.0, 1.0]));
ctl_pts.push(ControlPoint::new([1.0, 0.0], [1.0, 1.0, 1.0]));
ctl_pts.push(ControlPoint::new([0.5, 0.5], [0.0, 0.0, 1.0]));
}
{
let base = ctl_pts.len() as u32;
faces.push([base, base + 1, base + 4]);
faces.push([base + 1, base + 2, base + 4]);
faces.push([base + 2, base + 3, base + 4]);
faces.push([base + 3, base, base + 4]);
ctl_pts.push(ControlPoint::new([1.0, 0.0], [1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([1.0, 1.0], [1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 1.0], [-1.0, -1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.0, 0.0], [-1.0, 1.0, -1.0]));
ctl_pts.push(ControlPoint::new([0.5, 0.5], [0.0, 0.0, -1.0]));
}
for pt in ctl_pts {
let p: Vec3 = pt.dir.into();
let n: Vec3 = p.normalize();
let t: Vec2 = pt.uv.into();
vertices.push(Vertex {
position: (p / 2.0).into(),
normal: n.into(),
tex_coord: t.into(),
});
}
Mesh { faces, vertices }
}
#[test]
fn cube_tangents_should_equal_reference_values() {
let mut context = Context {
mesh: make_cube(),
results: Vec::new(),
};
let ret = generate_tangents(&mut context);
assert_eq!(true, ret);
let expected_results: Vec<Result> = vec![
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
0,
0,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
0,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
false,
0,
2,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
1,
0,
),
Result::new(
[-0.40824825, 0.81649655, 0.40824825],
[-0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
1,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
false,
1,
2,
),
Result::new(
[-0.40824825, 0.81649655, 0.40824825],
[-0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
2,
0,
),
Result::new(
[-0.40824825, 0.81649655, -0.40824825],
[0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
2,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
false,
2,
2,
),
Result::new(
[-0.40824825, 0.81649655, -0.40824825],
[0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
3,
0,
),
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
3,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
false,
3,
2,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
4,
0,
),
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
4,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
true,
4,
2,
),
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
5,
0,
),
Result::new(
[-0.40824825, 0.81649655, -0.40824825],
[0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
5,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
true,
5,
2,
),
Result::new(
[-0.40824825, 0.81649655, -0.40824825],
[0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
6,
0,
),
Result::new(
[-0.40824825, 0.81649655, 0.40824825],
[-0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
6,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
true,
6,
2,
),
Result::new(
[-0.40824825, 0.81649655, 0.40824825],
[-0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
7,
0,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
7,
1,
),
Result::new(
[0.00000000, 1.00000000, 0.00000000],
[0.00000000, 0.00000000, -1.00000000],
1.00000000,
1.00000000,
true,
7,
2,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
8,
0,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
8,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
8,
2,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
9,
0,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
9,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
9,
2,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
10,
0,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
10,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
10,
2,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
11,
0,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
11,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
11,
2,
),
Result::new(
[-0.40824825, 0.81649655, 0.40824825],
[-0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
12,
0,
),
Result::new(
[-0.40824825, 0.81649655, -0.40824825],
[0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
true,
12,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
12,
2,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
13,
0,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
13,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
13,
2,
),
Result::new(
[0.40824825, 0.81649655, -0.40824825],
[-0.40824825, 0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
14,
0,
),
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
14,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
14,
2,
),
Result::new(
[0.40824825, 0.81649655, 0.40824825],
[0.40824825, -0.40824825, -0.81649655],
1.00000000,
1.00000000,
false,
15,
0,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
15,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, 1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
15,
2,
),
Result::new(
[0.81649655, 0.40824825, 0.40824825],
[-0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
false,
16,
0,
),
Result::new(
[0.81649655, -0.40824825, 0.40824825],
[0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
false,
16,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
16,
2,
),
Result::new(
[0.81649655, -0.40824825, 0.40824825],
[0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
false,
17,
0,
),
Result::new(
[0.81649655, 0.40824825, -0.40824825],
[-0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
false,
17,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
17,
2,
),
Result::new(
[0.81649655, 0.40824825, -0.40824825],
[-0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
false,
18,
0,
),
Result::new(
[0.81649655, -0.40824825, -0.40824825],
[0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
false,
18,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
18,
2,
),
Result::new(
[0.81649655, -0.40824825, -0.40824825],
[0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
false,
19,
0,
),
Result::new(
[0.81649655, 0.40824825, 0.40824825],
[-0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
false,
19,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
false,
19,
2,
),
Result::new(
[0.81649655, -0.40824825, 0.40824825],
[0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
true,
20,
0,
),
Result::new(
[0.81649655, 0.40824825, 0.40824825],
[-0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
true,
20,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
true,
20,
2,
),
Result::new(
[0.81649655, 0.40824825, 0.40824825],
[-0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
true,
21,
0,
),
Result::new(
[0.81649655, -0.40824825, -0.40824825],
[0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
true,
21,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
true,
21,
2,
),
Result::new(
[0.81649655, -0.40824825, -0.40824825],
[0.40824825, -0.81649655, 0.40824825],
1.00000000,
1.00000000,
true,
22,
0,
),
Result::new(
[0.81649655, 0.40824825, -0.40824825],
[-0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
true,
22,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
true,
22,
2,
),
Result::new(
[0.81649655, 0.40824825, -0.40824825],
[-0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
true,
23,
0,
),
Result::new(
[0.81649655, -0.40824825, 0.40824825],
[0.40824825, -0.81649655, -0.40824825],
1.00000000,
1.00000000,
true,
23,
1,
),
Result::new(
[1.00000000, 0.00000000, 0.00000000],
[0.00000000, -1.00000000, 0.00000000],
1.00000000,
1.00000000,
true,
23,
2,
),
];
assert_eq!(expected_results, context.results);
}