Add XRView.transform

components/script/dom/webidls/XRView.webidl

@@ -14,5 +14,5 @@ interface XRView {
   readonly attribute XREye eye;
   readonly attribute Float32Array projectionMatrix;
   readonly attribute Float32Array viewMatrix;
-  // readonly attribute XRRigidTransform transform;
+  readonly attribute XRRigidTransform transform;
 };

components/script/dom/xrrigidtransform.rs

@@ -95,9 +95,8 @@ impl XRRigidTransformMethods for XRRigidTransform {
     }
     // https://immersive-web.github.io/webxr/#dom-xrrigidtransform-inverse
     fn Inverse(&self) -> DomRoot<XRRigidTransform> {
-        self.inverse.or_init(|| {
-            XRRigidTransform::new(&self.global(), self.transform.inverse())
-        })
+        self.inverse
+            .or_init(|| XRRigidTransform::new(&self.global(), self.transform.inverse()))
     }
 }
 

components/script/dom/xrview.rs

@@ -8,6 +8,7 @@ use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
 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 dom_struct::dom_struct;
 use euclid::{RigidTransform3D, Vector3D};
@@ -22,16 +23,18 @@ pub struct XRView {
     eye: XREye,
     proj: Heap<*mut JSObject>,
     view: Heap<*mut JSObject>,
+    transform: Dom<XRRigidTransform>,
 }
 
 impl XRView {
-    fn new_inherited(session: &XRSession, eye: XREye) -> XRView {
+    fn new_inherited(session: &XRSession, transform: &XRRigidTransform, eye: XREye) -> XRView {
         XRView {
             reflector_: Reflector::new(),
             session: Dom::from_ref(session),
             eye,
             proj: Heap::default(),
             view: Heap::default(),
+            transform: Dom::from_ref(transform),
         }
     }
 
@@ -43,12 +46,6 @@ impl XRView {
         pose: &RigidTransform3D<f64>,
         data: &WebVRFrameData,
     ) -> DomRoot<XRView> {
-        let ret = reflect_dom_object(
-            Box::new(XRView::new_inherited(session, eye)),
-            global,
-            XRViewBinding::Wrap,
-        );
-
         let vr_display = session.display();
 
         // XXXManishearth compute and cache projection matrices on the Display
@@ -65,11 +62,15 @@ impl XRView {
         };
 
         let offset = Vector3D::new(offset[0] as f64, offset[1] as f64, offset[2] as f64);
-        let view = pose
-            .post_mul(&offset.into())
-            .to_transform()
-            .cast()
-            .to_column_major_array();
+        let transform = pose.post_mul(&offset.into());
+        let view = transform.to_transform().cast().to_column_major_array();
+        let transform = XRRigidTransform::new(global, transform);
+
+        let ret = reflect_dom_object(
+            Box::new(XRView::new_inherited(session, &transform, eye)),
+            global,
+            XRViewBinding::Wrap,
+        );
 
         let cx = global.get_cx();
         unsafe {
@@ -101,4 +102,9 @@ impl XRViewMethods for XRView {
     unsafe fn ViewMatrix(&self, _cx: *mut JSContext) -> NonNull<JSObject> {
         NonNull::new(self.view.get()).unwrap()
     }
+
+    /// https://immersive-web.github.io/webxr/#dom-xrview-transform
+    fn Transform(&self) -> DomRoot<XRRigidTransform> {
+        DomRoot::from_ref(&self.transform)
+    }
 }