1 files changed, 147 insertions, 0 deletions
diff --git a/components/script/dom/xrray.rs b/components/script/dom/xrray.rs
new file mode 100644
index 00000000000..37262732c3a
--- /dev/null
+++ b/components/script/dom/xrray.rs
@@ -0,0 +1,147 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use crate::dom::bindings::codegen::Bindings::DOMPointBinding::DOMPointInit;
+use crate::dom::bindings::codegen::Bindings::XRRayBinding::{XRRayDirectionInit, XRRayMethods};
+use crate::dom::bindings::error::{Error, Fallible};
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::bindings::utils::create_typed_array;
+use crate::dom::dompointreadonly::DOMPointReadOnly;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::window::Window;
+use crate::dom::xrrigidtransform::XRRigidTransform;
+use crate::script_runtime::JSContext;
+use dom_struct::dom_struct;
+use euclid::{Angle, RigidTransform3D, Rotation3D, Vector3D};
+use js::jsapi::{Heap, JSObject};
+use std::ptr::NonNull;
+use webxr_api::{ApiSpace, Ray};
+
+#[dom_struct]
+pub struct XRRay {
+    reflector_: Reflector,
+    #[ignore_malloc_size_of = "defined in webxr"]
+    ray: Ray<ApiSpace>,
+    #[ignore_malloc_size_of = "defined in mozjs"]
+    matrix: Heap<*mut JSObject>,
+}
+
+impl XRRay {
+    fn new_inherited(ray: Ray<ApiSpace>) -> XRRay {
+        XRRay {
+            reflector_: Reflector::new(),
+            ray,
+            matrix: Heap::default(),
+        }
+    }
+
+    pub fn new(global: &GlobalScope, ray: Ray<ApiSpace>) -> DomRoot<XRRay> {
+        reflect_dom_object(Box::new(XRRay::new_inherited(ray)), global)
+    }
+
+    #[allow(non_snake_case)]
+    /// https://immersive-web.github.io/hit-test/#dom-xrray-xrray
+    pub fn Constructor(
+        window: &Window,
+        origin: &DOMPointInit,
+        direction: &XRRayDirectionInit,
+    ) -> Fallible<DomRoot<Self>> {
+        if origin.w != 1.0 {
+            return Err(Error::Type("Origin w coordinate must be 1".into()));
+        }
+        if *direction.w != 0.0 {
+            return Err(Error::Type("Direction w coordinate must be 0".into()));
+        }
+        if *direction.x == 0.0 && *direction.y == 0.0 && *direction.z == 0.0 {
+            return Err(Error::Type(
+                "Direction vector cannot have zero length".into(),
+            ));
+        }
+
+        let origin = Vector3D::new(origin.x as f32, origin.y as f32, origin.z as f32);
+        let direction = Vector3D::new(
+            *direction.x as f32,
+            *direction.y as f32,
+            *direction.z as f32,
+        )
+        .normalize();
+
+        Ok(Self::new(&window.global(), Ray { origin, direction }))
+    }
+
+    #[allow(non_snake_case)]
+    /// https://immersive-web.github.io/hit-test/#dom-xrray-xrray-transform
+    pub fn Constructor_(window: &Window, transform: &XRRigidTransform) -> Fallible<DomRoot<Self>> {
+        let transform = transform.transform();
+        let origin = transform.translation;
+        let direction = transform
+            .rotation
+            .transform_vector3d(Vector3D::new(0., 0., -1.));
+
+        Ok(Self::new(&window.global(), Ray { origin, direction }))
+    }
+
+    pub fn ray(&self) -> Ray<ApiSpace> {
+        self.ray
+    }
+}
+
+impl XRRayMethods for XRRay {
+    /// https://immersive-web.github.io/hit-test/#dom-xrray-origin
+    fn Origin(&self) -> DomRoot<DOMPointReadOnly> {
+        DOMPointReadOnly::new(
+            &self.global(),
+            self.ray.origin.x as f64,
+            self.ray.origin.y as f64,
+            self.ray.origin.z as f64,
+            1.,
+        )
+    }
+
+    /// https://immersive-web.github.io/hit-test/#dom-xrray-direction
+    fn Direction(&self) -> DomRoot<DOMPointReadOnly> {
+        DOMPointReadOnly::new(
+            &self.global(),
+            self.ray.direction.x as f64,
+            self.ray.direction.y as f64,
+            self.ray.direction.z as f64,
+            0.,
+        )
+    }
+
+    /// https://immersive-web.github.io/hit-test/#dom-xrray-matrix
+    fn Matrix(&self, _cx: JSContext) -> NonNull<JSObject> {
+        // https://immersive-web.github.io/hit-test/#xrray-obtain-the-matrix
+        // Step 1
+        if self.matrix.get().is_null() {
+            let cx = self.global().get_cx();
+            // Step 2
+            let z = Vector3D::new(0., 0., -1.);
+            // Step 3
+            let axis = z.cross(self.ray.direction);
+            // Step 4
+            let cos_angle = z.dot(self.ray.direction);
+            // Step 5
+            let rotation = if cos_angle > -1. && cos_angle < 1. {
+                Rotation3D::around_axis(axis, Angle::radians(cos_angle.acos()))
+            } else if cos_angle == -1. {
+                let axis = Vector3D::new(1., 0., 0.);
+                Rotation3D::around_axis(axis, Angle::radians(cos_angle.acos()))
+            } else {
+                Rotation3D::identity()
+            };
+            // Step 6
+            let translation = self.ray.origin;
+            // Step 7
+            // According to the spec all matrices are column-major,
+            // however euclid uses row vectors so we use .to_row_major_array()
+            let arr = RigidTransform3D::new(rotation, translation)
+                .to_transform()
+                .to_row_major_array();
+            create_typed_array(cx, &arr, &self.matrix);
+        }
+        NonNull::new(self.matrix.get()).unwrap()
+    }
+}