Hook webxr data into XRFrame/XRView/XRSpace

12 files changed, 110 insertions, 106 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 44e3b8c3845..889036eff06 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -57,8 +57,8 @@ use devtools_traits::{CSSError, TimelineMarkerType, WorkerId};
 use encoding_rs::{Decoder, Encoding};
 use euclid::Length as EuclidLength;
 use euclid::{
-    Point2D, Rect, RigidTransform3D, Rotation3D, Transform2D, Transform3D, TypedScale, TypedSize2D,
-    Vector2D,
+    Point2D, Rect, RigidTransform3D, Rotation3D, Transform2D, Transform3D, TypedRigidTransform3D,
+    TypedScale, TypedSize2D, Vector2D,
 };
 use html5ever::buffer_queue::BufferQueue;
 use html5ever::{LocalName, Namespace, Prefix, QualName};
@@ -486,7 +486,7 @@ unsafe_no_jsmanaged_fields!(WebGLVersion);
 unsafe_no_jsmanaged_fields!(WebGLSLVersion);
 unsafe_no_jsmanaged_fields!(MediaList);
 unsafe_no_jsmanaged_fields!(WebVRGamepadData, WebVRGamepadState, WebVRGamepadHand);
-unsafe_no_jsmanaged_fields!(webxr_api::Registry, webxr_api::Session);
+unsafe_no_jsmanaged_fields!(webxr_api::Registry, webxr_api::Session, webxr_api::Frame);
 unsafe_no_jsmanaged_fields!(ScriptToConstellationChan);
 unsafe_no_jsmanaged_fields!(InteractiveMetrics);
 unsafe_no_jsmanaged_fields!(InteractiveWindow);
@@ -607,6 +607,13 @@ unsafe impl<T, U> JSTraceable for TypedScale<f32, T, U> {
     }
 }
 
+unsafe impl<T, U> JSTraceable for TypedRigidTransform3D<f32, T, U> {
+    #[inline]
+    unsafe fn trace(&self, _trc: *mut JSTracer) {
+        // Do nothing
+    }
+}
+
 unsafe impl<T> JSTraceable for EuclidLength<u64, T> {
     #[inline]
     unsafe fn trace(&self, _trc: *mut JSTracer) {
diff --git a/components/script/dom/vrdisplay.rs b/components/script/dom/vrdisplay.rs
index 9f8e1a8f68e..36778ca6f35 100644
--- a/components/script/dom/vrdisplay.rs
+++ b/components/script/dom/vrdisplay.rs
@@ -839,7 +839,7 @@ impl VRDisplay {
 
         let now = self.global().as_window().Performance().Now();
 
-        if let Some(session) = self.xr_session.get() {
+        if let Some(_) = self.xr_session.get() {
             unreachable!("old webxr-on-webvr cruft")
         } else {
             self.running_display_raf.set(true);
diff --git a/components/script/dom/webidls/XRView.webidl b/components/script/dom/webidls/XRView.webidl
index c56342c6469..ceea69aaa89 100644
--- a/components/script/dom/webidls/XRView.webidl
+++ b/components/script/dom/webidls/XRView.webidl
@@ -6,7 +6,8 @@
 
 enum XREye {
   "left",
-  "right"
+  "right",
+  "unknown",
 };
 
 [SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
diff --git a/components/script/dom/xrframe.rs b/components/script/dom/xrframe.rs
index 04fb1d4ee7f..dad29ea9b9b 100644
--- a/components/script/dom/xrframe.rs
+++ b/components/script/dom/xrframe.rs
@@ -15,7 +15,6 @@ use crate::dom::xrsession::XRSession;
 use crate::dom::xrspace::XRSpace;
 use crate::dom::xrviewerpose::XRViewerPose;
 use dom_struct::dom_struct;
-use webvr_traits::WebVRFrameData;
 use webxr_api::Frame;
 
 #[dom_struct]
@@ -23,11 +22,11 @@ pub struct XRFrame {
     reflector_: Reflector,
     session: Dom<XRSession>,
     #[ignore_malloc_size_of = "defined in rust-webvr"]
-    data: WebVRFrameData,
+    data: Frame,
 }
 
 impl XRFrame {
-    fn new_inherited(session: &XRSession, data: WebVRFrameData) -> XRFrame {
+    fn new_inherited(session: &XRSession, data: Frame) -> XRFrame {
         XRFrame {
             reflector_: Reflector::new(),
             session: Dom::from_ref(session),
@@ -36,7 +35,6 @@ impl XRFrame {
     }
 
     pub fn new(global: &GlobalScope, session: &XRSession, data: Frame) -> DomRoot<XRFrame> {
-        let data = unimplemented!();
         reflect_dom_object(
             Box::new(XRFrame::new_inherited(session, data)),
             global,
@@ -60,12 +58,7 @@ impl XRFrameMethods for XRFrame {
             return Err(Error::InvalidState);
         }
         let pose = reference.get_viewer_pose(&self.data);
-        Ok(Some(XRViewerPose::new(
-            &self.global(),
-            &self.session,
-            pose,
-            &self.data,
-        )))
+        Ok(Some(XRViewerPose::new(&self.global(), &self.session, pose)))
     }
 
     /// https://immersive-web.github.io/webxr/#dom-xrframe-getpose
diff --git a/components/script/dom/xrinputsource.rs b/components/script/dom/xrinputsource.rs
index 2b623864d56..108ca16b9fc 100644
--- a/components/script/dom/xrinputsource.rs
+++ b/components/script/dom/xrinputsource.rs
@@ -10,10 +10,10 @@ use crate::dom::bindings::codegen::Bindings::XRInputSourceBinding::{
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::{Dom, DomRoot, MutNullableDom};
 use crate::dom::globalscope::GlobalScope;
-use crate::dom::xrsession::XRSession;
+use crate::dom::xrsession::{ApiPose, XRSession};
 use crate::dom::xrspace::XRSpace;
 use dom_struct::dom_struct;
-use webvr_traits::{WebVRGamepadData, WebVRGamepadHand, WebVRGamepadState, WebVRPose};
+use webvr_traits::{WebVRGamepadData, WebVRGamepadHand, WebVRGamepadState};
 
 #[dom_struct]
 pub struct XRInputSource {
@@ -58,8 +58,8 @@ impl XRInputSource {
         *self.state.borrow_mut() = state;
     }
 
-    pub fn pose(&self) -> WebVRPose {
-        self.state.borrow().pose
+    pub fn pose(&self) -> ApiPose {
+        unimplemented!()
     }
 }
 
diff --git a/components/script/dom/xrpose.rs b/components/script/dom/xrpose.rs
index 9f8aec3a366..a9d24f5a0d3 100644
--- a/components/script/dom/xrpose.rs
+++ b/components/script/dom/xrpose.rs
@@ -8,8 +8,8 @@ use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::xrrigidtransform::XRRigidTransform;
+use crate::dom::xrsession::ApiRigidTransform;
 use dom_struct::dom_struct;
-use euclid::RigidTransform3D;
 
 #[dom_struct]
 pub struct XRPose {
@@ -26,7 +26,7 @@ impl XRPose {
     }
 
     #[allow(unused)]
-    pub fn new(global: &GlobalScope, transform: RigidTransform3D<f64>) -> DomRoot<XRPose> {
+    pub fn new(global: &GlobalScope, transform: ApiRigidTransform) -> DomRoot<XRPose> {
         let transform = XRRigidTransform::new(global, transform);
         reflect_dom_object(
             Box::new(XRPose::new_inherited(&transform)),
diff --git a/components/script/dom/xrreferencespace.rs b/components/script/dom/xrreferencespace.rs
index c65ba7dad3e..4e570817fb8 100644
--- a/components/script/dom/xrreferencespace.rs
+++ b/components/script/dom/xrreferencespace.rs
@@ -10,11 +10,13 @@ use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::xrrigidtransform::XRRigidTransform;
-use crate::dom::xrsession::XRSession;
+use crate::dom::xrsession::{
+    cast_transform, cast_transform_to_pose, ApiPose, ApiRigidTransform, XRSession,
+};
 use crate::dom::xrspace::XRSpace;
 use dom_struct::dom_struct;
-use euclid::{RigidTransform3D, Vector3D};
-use webvr_traits::WebVRFrameData;
+use euclid::{TypedRigidTransform3D, TypedVector3D};
+use webxr_api::Frame;
 
 #[dom_struct]
 pub struct XRReferenceSpace {
@@ -80,7 +82,7 @@ impl XRReferenceSpace {
     ///
     /// This is equivalent to `get_pose(self).inverse() * get_pose(viewerSpace)` (in column vector notation),
     /// however we specialize it to be efficient
-    pub fn get_viewer_pose(&self, base_pose: &WebVRFrameData) -> RigidTransform3D<f64> {
+    pub fn get_viewer_pose(&self, base_pose: &Frame) -> ApiRigidTransform {
         let pose = self.get_unoffset_viewer_pose(base_pose);
 
         // This may change, see https://github.com/immersive-web/webxr/issues/567
@@ -98,8 +100,8 @@ impl XRReferenceSpace {
     /// Gets pose of the viewer with respect to this space
     ///
     /// Does not apply originOffset, use get_viewer_pose instead if you need it
-    pub fn get_unoffset_viewer_pose(&self, base_pose: &WebVRFrameData) -> RigidTransform3D<f64> {
-        let viewer_pose = XRSpace::pose_to_transform(&base_pose.pose);
+    pub fn get_unoffset_viewer_pose(&self, base_pose: &Frame) -> ApiRigidTransform {
+        let viewer_pose = cast_transform(base_pose.transform);
         // all math is in column-vector notation
         // we use the following equation to verify correctness here:
         // get_viewer_pose(space) = get_pose(space).inverse() * get_pose(viewer_space)
@@ -120,13 +122,13 @@ impl XRReferenceSpace {
                 //                            = Translate(2) * viewer_pose
 
                 // assume approximate user height of 2 meters
-                let floor_to_eye: RigidTransform3D<f64> = Vector3D::new(0., 2., 0.).into();
+                let floor_to_eye: ApiRigidTransform = TypedVector3D::new(0., 2., 0.).into();
                 floor_to_eye.pre_mul(&viewer_pose)
             },
             XRReferenceSpaceType::Viewer => {
                 // This reference space follows the viewer around, so the viewer is
                 // always at an identity transform with respect to it
-                RigidTransform3D::identity()
+                TypedRigidTransform3D::identity()
             },
             _ => unimplemented!(),
         }
@@ -137,7 +139,7 @@ impl XRReferenceSpace {
     /// The reference origin used is common between all
     /// get_pose calls for spaces from the same device, so this can be used to compare
     /// with other spaces
-    pub fn get_pose(&self, base_pose: &WebVRFrameData) -> RigidTransform3D<f64> {
+    pub fn get_pose(&self, base_pose: &Frame) -> ApiPose {
         let pose = self.get_unoffset_pose(base_pose);
 
         // This may change, see https://github.com/immersive-web/webxr/issues/567
@@ -148,21 +150,21 @@ impl XRReferenceSpace {
     /// Gets pose represented by this space
     ///
     /// Does not apply originOffset, use get_viewer_pose instead if you need it
-    pub fn get_unoffset_pose(&self, base_pose: &WebVRFrameData) -> RigidTransform3D<f64> {
+    pub fn get_unoffset_pose(&self, base_pose: &Frame) -> ApiPose {
         match self.ty {
             XRReferenceSpaceType::Local => {
                 // The eye-level pose is basically whatever the headset pose was at t=0, which
                 // for most devices is (0, 0, 0)
-                RigidTransform3D::identity()
+                TypedRigidTransform3D::identity()
             },
             XRReferenceSpaceType::Local_floor => {
                 // XXXManishearth support getting floor info from stage parameters
 
                 // Assume approximate height of 2m
                 // the floor-level space is 2m below the eye-level space, which is (0, 0, 0)
-                Vector3D::new(0., -2., 0.).into()
+                TypedVector3D::new(0., -2., 0.).into()
             },
-            XRReferenceSpaceType::Viewer => XRSpace::pose_to_transform(&base_pose.pose),
+            XRReferenceSpaceType::Viewer => cast_transform_to_pose(base_pose.transform),
             _ => unimplemented!(),
         }
     }
diff --git a/components/script/dom/xrrigidtransform.rs b/components/script/dom/xrrigidtransform.rs
index f75d3f085fb..5e1f720411e 100644
--- a/components/script/dom/xrrigidtransform.rs
+++ b/components/script/dom/xrrigidtransform.rs
@@ -14,8 +14,9 @@ use crate::dom::dompointreadonly::DOMPointReadOnly;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::vrframedata::create_typed_array;
 use crate::dom::window::Window;
+use crate::dom::xrsession::ApiRigidTransform;
 use dom_struct::dom_struct;
-use euclid::{RigidTransform3D, Rotation3D, Vector3D};
+use euclid::{TypedRigidTransform3D, TypedRotation3D, TypedVector3D};
 use js::jsapi::{Heap, JSContext, JSObject};
 use std::ptr::NonNull;
 
@@ -25,14 +26,14 @@ pub struct XRRigidTransform {
     position: MutNullableDom<DOMPointReadOnly>,
     orientation: MutNullableDom<DOMPointReadOnly>,
     #[ignore_malloc_size_of = "defined in euclid"]
-    transform: RigidTransform3D<f64>,
+    transform: ApiRigidTransform,
     inverse: MutNullableDom<XRRigidTransform>,
     #[ignore_malloc_size_of = "defined in mozjs"]
     matrix: Heap<*mut JSObject>,
 }
 
 impl XRRigidTransform {
-    fn new_inherited(transform: RigidTransform3D<f64>) -> XRRigidTransform {
+    fn new_inherited(transform: ApiRigidTransform) -> XRRigidTransform {
         XRRigidTransform {
             reflector_: Reflector::new(),
             position: MutNullableDom::default(),
@@ -43,10 +44,7 @@ impl XRRigidTransform {
         }
     }
 
-    pub fn new(
-        global: &GlobalScope,
-        transform: RigidTransform3D<f64>,
-    ) -> DomRoot<XRRigidTransform> {
+    pub fn new(global: &GlobalScope, transform: ApiRigidTransform) -> DomRoot<XRRigidTransform> {
         reflect_dom_object(
             Box::new(XRRigidTransform::new_inherited(transform)),
             global,
@@ -55,7 +53,7 @@ impl XRRigidTransform {
     }
 
     pub fn identity(window: &GlobalScope) -> DomRoot<XRRigidTransform> {
-        let transform = RigidTransform3D::identity();
+        let transform = TypedRigidTransform3D::identity();
         XRRigidTransform::new(window, transform)
     }
 
@@ -72,14 +70,14 @@ impl XRRigidTransform {
             )));
         }
 
-        let translate = Vector3D::new(position.x as f64, position.y as f64, position.z as f64);
-        let rotate = Rotation3D::unit_quaternion(
-            orientation.x as f64,
-            orientation.y as f64,
-            orientation.z as f64,
-            orientation.w as f64,
+        let translate = TypedVector3D::new(position.x as f32, position.y as f32, position.z as f32);
+        let rotate = TypedRotation3D::unit_quaternion(
+            orientation.x as f32,
+            orientation.y as f32,
+            orientation.z as f32,
+            orientation.w as f32,
         );
-        let transform = RigidTransform3D::new(rotate, translate);
+        let transform = TypedRigidTransform3D::new(rotate, translate);
         Ok(XRRigidTransform::new(&window.global(), transform))
     }
 }
@@ -89,14 +87,20 @@ impl XRRigidTransformMethods for XRRigidTransform {
     fn Position(&self) -> DomRoot<DOMPointReadOnly> {
         self.position.or_init(|| {
             let t = &self.transform.translation;
-            DOMPointReadOnly::new(&self.global(), t.x, t.y, t.z, 1.0)
+            DOMPointReadOnly::new(&self.global(), t.x.into(), t.y.into(), t.z.into(), 1.0)
         })
     }
     // https://immersive-web.github.io/webxr/#dom-xrrigidtransform-orientation
     fn Orientation(&self) -> DomRoot<DOMPointReadOnly> {
         self.orientation.or_init(|| {
             let r = &self.transform.rotation;
-            DOMPointReadOnly::new(&self.global(), r.i, r.j, r.k, r.r)
+            DOMPointReadOnly::new(
+                &self.global(),
+                r.i.into(),
+                r.j.into(),
+                r.k.into(),
+                r.r.into(),
+            )
         })
     }
     // https://immersive-web.github.io/webxr/#dom-xrrigidtransform-inverse
@@ -114,7 +118,7 @@ impl XRRigidTransformMethods for XRRigidTransform {
             let cx = self.global().get_cx();
             // According to the spec all matrices are column-major,
             // however euclid uses row vectors so we use .to_row_major_array()
-            let arr = self.transform.to_transform().cast().to_row_major_array();
+            let arr = self.transform.to_transform().to_row_major_array();
             create_typed_array(cx, &arr, &self.matrix);
         }
         NonNull::new(self.matrix.get()).unwrap()
@@ -123,7 +127,7 @@ impl XRRigidTransformMethods for XRRigidTransform {
 
 impl XRRigidTransform {
     /// https://immersive-web.github.io/webxr/#dom-xrpose-transform
-    pub fn transform(&self) -> RigidTransform3D<f64> {
+    pub fn transform(&self) -> ApiRigidTransform {
         self.transform
     }
 }
diff --git a/components/script/dom/xrsession.rs b/components/script/dom/xrsession.rs
index 172a2ccebbd..45d9dc54a29 100644
--- a/components/script/dom/xrsession.rs
+++ b/components/script/dom/xrsession.rs
@@ -32,7 +32,7 @@ use crate::dom::xrspace::XRSpace;
 use crate::dom::xrwebgllayer::XRWebGLLayer;
 use crate::task_source::TaskSource;
 use dom_struct::dom_struct;
-use euclid::Vector3D;
+use euclid::TypedRigidTransform3D;
 use ipc_channel::ipc::IpcSender;
 use ipc_channel::router::ROUTER;
 use profile_traits::ipc;
@@ -92,12 +92,9 @@ impl XRSession {
         self.base_layer.set(Some(layer))
     }
 
-    pub fn left_eye_params_offset(&self) -> Vector3D<f64> {
-        unimplemented!()
-    }
-
-    pub fn right_eye_params_offset(&self) -> Vector3D<f64> {
-        unimplemented!()
+    pub fn with_session<F: FnOnce(&Session)>(&self, with: F) {
+        let session = self.session.borrow();
+        with(&session)
     }
 
     /// https://immersive-web.github.io/webxr/#xr-animation-frame
@@ -278,3 +275,22 @@ impl XRSessionMethods for XRSession {
         unimplemented!()
     }
 }
+
+#[derive(Clone, Copy, Debug)]
+pub struct ApiSpace;
+// The pose of an object in native-space. Should never be exposed.
+pub type ApiPose = TypedRigidTransform3D<f32, ApiSpace, webxr_api::Native>;
+// A transform between objects in some API-space
+pub type ApiRigidTransform = TypedRigidTransform3D<f32, ApiSpace, ApiSpace>;
+
+#[allow(unsafe_code)]
+pub fn cast_transform_to_pose<T>(
+    transform: TypedRigidTransform3D<f32, T, webxr_api::Native>,
+) -> ApiPose {
+    unsafe { mem::transmute(transform) }
+}
+
+#[allow(unsafe_code)]
+pub fn cast_transform<T, U>(transform: TypedRigidTransform3D<f32, T, U>) -> ApiRigidTransform {
+    unsafe { mem::transmute(transform) }
+}
diff --git a/components/script/dom/xrspace.rs b/components/script/dom/xrspace.rs
index 1614db9f6d4..ad76be52518 100644
--- a/components/script/dom/xrspace.rs
+++ b/components/script/dom/xrspace.rs
@@ -10,10 +10,9 @@ use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::xrinputsource::XRInputSource;
 use crate::dom::xrreferencespace::XRReferenceSpace;
-use crate::dom::xrsession::XRSession;
+use crate::dom::xrsession::{ApiPose, XRSession};
 use dom_struct::dom_struct;
-use euclid::{RigidTransform3D, Rotation3D, Vector3D};
-use webvr_traits::{WebVRFrameData, WebVRPose};
+use webxr_api::Frame;
 
 #[dom_struct]
 pub struct XRSpace {
@@ -58,30 +57,16 @@ impl XRSpace {
     /// The reference origin used is common between all
     /// get_pose calls for spaces from the same device, so this can be used to compare
     /// with other spaces
-    pub fn get_pose(&self, base_pose: &WebVRFrameData) -> RigidTransform3D<f64> {
+    pub fn get_pose(&self, base_pose: &Frame) -> ApiPose {
         if let Some(reference) = self.downcast::<XRReferenceSpace>() {
             reference.get_pose(base_pose)
         } else if let Some(source) = self.input_source.get() {
-            XRSpace::pose_to_transform(&source.pose())
+            source.pose()
         } else {
             unreachable!()
         }
     }
 
-    pub fn pose_to_transform(pose: &WebVRPose) -> RigidTransform3D<f64> {
-        let pos = pose.position.unwrap_or([0., 0., 0.]);
-        let translation = Vector3D::new(pos[0] as f64, pos[1] as f64, pos[2] as f64);
-        let orient = pose.orientation.unwrap_or([0., 0., 0., 0.]);
-        let rotation = Rotation3D::quaternion(
-            orient[0] as f64,
-            orient[1] as f64,
-            orient[2] as f64,
-            orient[3] as f64,
-        )
-        .normalize();
-        RigidTransform3D::new(rotation, translation)
-    }
-
     pub fn session(&self) -> &XRSession {
         &self.session
     }
diff --git a/components/script/dom/xrview.rs b/components/script/dom/xrview.rs
index bac9e3612a1..122ba83fbbf 100644
--- a/components/script/dom/xrview.rs
+++ b/components/script/dom/xrview.rs
@@ -9,12 +9,11 @@ use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::vrframedata::create_typed_array;
 use crate::dom::xrrigidtransform::XRRigidTransform;
-use crate::dom::xrsession::XRSession;
+use crate::dom::xrsession::{cast_transform, ApiRigidTransform, XRSession};
 use dom_struct::dom_struct;
-use euclid::RigidTransform3D;
 use js::jsapi::{Heap, JSContext, JSObject};
 use std::ptr::NonNull;
-use webvr_traits::WebVRFrameData;
+use webxr_api::View;
 
 #[dom_struct]
 pub struct XRView {
@@ -41,25 +40,15 @@ impl XRView {
     }
 
     #[allow(unsafe_code)]
-    pub fn new(
+    pub fn new<V: Copy>(
         global: &GlobalScope,
         session: &XRSession,
+        view: &View<V>,
         eye: XREye,
-        pose: &RigidTransform3D<f64>,
-        data: &WebVRFrameData,
+        pose: &ApiRigidTransform,
     ) -> DomRoot<XRView> {
         // XXXManishearth compute and cache projection matrices on the Display
-        let (proj, offset) = if eye == XREye::Left {
-            (
-                &data.left_projection_matrix,
-                session.left_eye_params_offset(),
-            )
-        } else {
-            (
-                &data.right_projection_matrix,
-                session.right_eye_params_offset(),
-            )
-        };
+        let offset = cast_transform(view.transform);
 
         let transform = pose.post_mul(&offset.into());
         let transform = XRRigidTransform::new(global, transform);
@@ -70,9 +59,11 @@ impl XRView {
             XRViewBinding::Wrap,
         );
 
+        // row_major since euclid uses row vectors
+        let proj = view.projection.to_row_major_array();
         let cx = global.get_cx();
         unsafe {
-            create_typed_array(cx, proj, &ret.proj);
+            create_typed_array(cx, &proj, &ret.proj);
         }
         ret
     }
diff --git a/components/script/dom/xrviewerpose.rs b/components/script/dom/xrviewerpose.rs
index 92caa7f037b..12c8267aa68 100644
--- a/components/script/dom/xrviewerpose.rs
+++ b/components/script/dom/xrviewerpose.rs
@@ -10,14 +10,13 @@ use crate::dom::bindings::root::DomRoot;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::xrpose::XRPose;
 use crate::dom::xrrigidtransform::XRRigidTransform;
-use crate::dom::xrsession::XRSession;
+use crate::dom::xrsession::{ApiRigidTransform, XRSession};
 use crate::dom::xrview::XRView;
 use dom_struct::dom_struct;
-use euclid::RigidTransform3D;
 use js::conversions::ToJSValConvertible;
 use js::jsapi::{Heap, JSContext};
 use js::jsval::{JSVal, UndefinedValue};
-use webvr_traits::WebVRFrameData;
+use webxr_api::Views;
 
 #[dom_struct]
 pub struct XRViewerPose {
@@ -38,11 +37,18 @@ impl XRViewerPose {
     pub fn new(
         global: &GlobalScope,
         session: &XRSession,
-        pose: RigidTransform3D<f64>,
-        data: &WebVRFrameData,
+        pose: ApiRigidTransform,
     ) -> DomRoot<XRViewerPose> {
-        let left = XRView::new(global, session, XREye::Left, &pose, &data);
-        let right = XRView::new(global, session, XREye::Right, &pose, &data);
+        rooted_vec!(let mut views);
+        session.with_session(|s| match s.views() {
+            Views::Mono(view) => {
+                views.push(XRView::new(global, session, &view, XREye::Unknown, &pose))
+            },
+            Views::Stereo(left, right) => {
+                views.push(XRView::new(global, session, &left, XREye::Left, &pose));
+                views.push(XRView::new(global, session, &right, XREye::Right, &pose));
+            },
+        });
         let transform = XRRigidTransform::new(global, pose);
         let pose = reflect_dom_object(
             Box::new(XRViewerPose::new_inherited(&transform)),
@@ -53,8 +59,7 @@ impl XRViewerPose {
         unsafe {
             let cx = global.get_cx();
             rooted!(in(cx) let mut jsval = UndefinedValue());
-            let vec = vec![left, right];
-            vec.to_jsval(cx, jsval.handle_mut());
+            views.to_jsval(cx, jsval.handle_mut());
             pose.views.set(jsval.get());
         }