Vendor dependencies for 0.3.0 release

vendor/naga_oil/examples/bevy_pbr_wgsl/skinning.wgsl

@@ -0,0 +1,41 @@
+#define_import_path bevy_pbr::skinning
+
+#ifdef SKINNED
+
+@group(2) @binding(1)
+var<uniform> joint_matrices: SkinnedMesh;
+
+fn skin_model(
+    indexes: vec4<u32>,
+    weights: vec4<f32>,
+) -> mat4x4<f32> {
+    return weights.x * joint_matrices.data[indexes.x]
+        + weights.y * joint_matrices.data[indexes.y]
+        + weights.z * joint_matrices.data[indexes.z]
+        + weights.w * joint_matrices.data[indexes.w];
+}
+
+fn inverse_transpose_3x3(in: mat3x3<f32>) -> mat3x3<f32> {
+    let x = cross(in[1], in[2]);
+    let y = cross(in[2], in[0]);
+    let z = cross(in[0], in[1]);
+    let det = dot(in[2], z);
+    return mat3x3<f32>(
+        x / det,
+        y / det,
+        z / det
+    );
+}
+
+fn skin_normals(
+    model: mat4x4<f32>,
+    normal: vec3<f32>,
+) -> vec3<f32> {
+    return inverse_transpose_3x3(mat3x3<f32>(
+        model[0].xyz,
+        model[1].xyz,
+        model[2].xyz
+    )) * normal;
+}
+
+#endif