1#define_import_path bevy_pbr::skinning
2
3#ifdef SKINNED
4
5@group(2) @binding(1)
6var<uniform> joint_matrices: SkinnedMesh;
7
8fn skin_model(
9    indexes: vec4<u32>,
10    weights: vec4<f32>,
11) -> mat4x4<f32> {
12    return weights.x * joint_matrices.data[indexes.x]
13        + weights.y * joint_matrices.data[indexes.y]
14        + weights.z * joint_matrices.data[indexes.z]
15        + weights.w * joint_matrices.data[indexes.w];
16}
17
18fn inverse_transpose_3x3(in: mat3x3<f32>) -> mat3x3<f32> {
19    let x = cross(in[1], in[2]);
20    let y = cross(in[2], in[0]);
21    let z = cross(in[0], in[1]);
22    let det = dot(in[2], z);
23    return mat3x3<f32>(
24        x / det,
25        y / det,
26        z / det
27    );
28}
29
30fn skin_normals(
31    model: mat4x4<f32>,
32    normal: vec3<f32>,
33) -> vec3<f32> {
34    return inverse_transpose_3x3(mat3x3<f32>(
35        model[0].xyz,
36        model[1].xyz,
37        model[2].xyz
38    )) * normal;
39}
40
41#endif