Auto merge of #23097 - Manishearth:transforms, r=asajeffrey

Properly support transforms in WebXR

Still need to test this

There are also a bunch of fixmes that I should get to in this PR.

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components/script/dom/bindings/trace.rs

@@ -56,7 +56,9 @@ use cssparser::RGBA;
 use devtools_traits::{CSSError, TimelineMarkerType, WorkerId};
 use encoding_rs::{Decoder, Encoding};
 use euclid::Length as EuclidLength;
-use euclid::{Point2D, Rect, Transform2D, Transform3D, TypedScale, TypedSize2D, Vector2D};
+use euclid::{
+    Point2D, Rect, Rotation3D, Transform2D, Transform3D, TypedScale, TypedSize2D, Vector2D,
+};
 use html5ever::buffer_queue::BufferQueue;
 use html5ever::{LocalName, Namespace, Prefix, QualName};
 use http::header::HeaderMap;
@@ -491,6 +493,8 @@ unsafe_no_jsmanaged_fields!(RenderApiSender);
 unsafe_no_jsmanaged_fields!(ResourceFetchTiming);
 unsafe_no_jsmanaged_fields!(Timespec);
 unsafe_no_jsmanaged_fields!(HTMLMediaElementFetchContext);
+unsafe_no_jsmanaged_fields!(Rotation3D<f64>, Transform2D<f32>, Transform3D<f64>);
+unsafe_no_jsmanaged_fields!(Point2D<f32>, Vector2D<f32>, Rect<Au>, Rect<f32>);
 
 unsafe impl<'a> JSTraceable for &'a str {
     #[inline]
@@ -582,27 +586,6 @@ where
     }
 }
 
-unsafe impl JSTraceable for Transform2D<f32> {
-    #[inline]
-    unsafe fn trace(&self, _trc: *mut JSTracer) {
-        // Do nothing
-    }
-}
-
-unsafe impl JSTraceable for Transform3D<f64> {
-    #[inline]
-    unsafe fn trace(&self, _trc: *mut JSTracer) {
-        // Do nothing
-    }
-}
-
-unsafe impl JSTraceable for Point2D<f32> {
-    #[inline]
-    unsafe fn trace(&self, _trc: *mut JSTracer) {
-        // Do nothing
-    }
-}
-
 unsafe impl<T, U> JSTraceable for TypedScale<f32, T, U> {
     #[inline]
     unsafe fn trace(&self, _trc: *mut JSTracer) {
@@ -610,13 +593,6 @@ unsafe impl<T, U> JSTraceable for TypedScale<f32, T, U> {
     }
 }
 
-unsafe impl JSTraceable for Vector2D<f32> {
-    #[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) {
@@ -624,20 +600,6 @@ unsafe impl<T> JSTraceable for EuclidLength<u64, T> {
     }
 }
 
-unsafe impl JSTraceable for Rect<Au> {
-    #[inline]
-    unsafe fn trace(&self, _trc: *mut JSTracer) {
-        // Do nothing
-    }
-}
-
-unsafe impl JSTraceable for Rect<f32> {
-    #[inline]
-    unsafe fn trace(&self, _trc: *mut JSTracer) {
-        // Do nothing
-    }
-}
-
 unsafe impl<U> JSTraceable for TypedSize2D<i32, U> {
     #[inline]
     unsafe fn trace(&self, _trc: *mut JSTracer) {

components/script/dom/vrdisplay.rs

@@ -173,6 +173,14 @@ impl VRDisplay {
             VRDisplayBinding::Wrap,
         )
     }
+
+    pub fn left_eye_params_offset(&self) -> [f32; 3] {
+        self.left_eye_params.get().offset_array()
+    }
+
+    pub fn right_eye_params_offset(&self) -> [f32; 3] {
+        self.right_eye_params.get().offset_array()
+    }
 }
 
 impl Drop for VRDisplay {

components/script/dom/vreyeparameters.rs

@@ -61,6 +61,10 @@ impl VREyeParameters {
 
         eye_parameters
     }
+
+    pub fn offset_array(&self) -> [f32; 3] {
+        self.parameters.borrow().offset
+    }
 }
 
 impl VREyeParametersMethods for VREyeParameters {

components/script/dom/webidls/XRRigidTransform.webidl

@@ -10,4 +10,5 @@ interface XRRigidTransform {
   readonly attribute DOMPointReadOnly position;
   readonly attribute DOMPointReadOnly orientation;
   // readonly attribute Float32Array matrix;
+  XRRigidTransform inverse();
 };

components/script/dom/xrframe.rs

@@ -5,13 +5,11 @@
 use crate::dom::bindings::codegen::Bindings::XRFrameBinding;
 use crate::dom::bindings::codegen::Bindings::XRFrameBinding::XRFrameMethods;
 use crate::dom::bindings::codegen::Bindings::XRViewBinding::XREye;
-use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::xrreferencespace::XRReferenceSpace;
 use crate::dom::xrsession::XRSession;
-use crate::dom::xrstationaryreferencespace::XRStationaryReferenceSpace;
 use crate::dom::xrview::XRView;
 use crate::dom::xrviewerpose::XRViewerPose;
 use dom_struct::dom_struct;
@@ -55,16 +53,21 @@ impl XRFrameMethods for XRFrame {
 
     /// https://immersive-web.github.io/webxr/#dom-xrframe-getviewerpose
     fn GetViewerPose(&self, reference: &XRReferenceSpace) -> Option<DomRoot<XRViewerPose>> {
-        if let Some(_) = reference.downcast::<XRStationaryReferenceSpace>() {
-            // For 3DOF devices all three kinds of reference spaces are identical
-            // FIXME(#23070, Manishearth) support originOffset
-            let left = XRView::new(&self.global(), &self.session, XREye::Left, &self.data);
-            let right = XRView::new(&self.global(), &self.session, XREye::Right, &self.data);
+        let pose = reference.get_viewer_pose(&self.data);
+        let left = XRView::new(
+            &self.global(),
+            &self.session,
+            XREye::Left,
+            &pose,
+            &self.data,
+        );
+        let right = XRView::new(
+            &self.global(),
+            &self.session,
+            XREye::Right,
+            &pose,
+            &self.data,
+        );
         Some(XRViewerPose::new(&self.global(), &left, &right))
-        } else {
-            // FIXME(#23070, Manishearth) support identity reference spaces
-            // depends on https://github.com/immersive-web/webxr/issues/565
-            None
-        }
     }
 }

components/script/dom/xrreferencespace.rs

@@ -4,6 +4,7 @@
 
 use crate::dom::bindings::codegen::Bindings::XRReferenceSpaceBinding;
 use crate::dom::bindings::codegen::Bindings::XRReferenceSpaceBinding::XRReferenceSpaceMethods;
+use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::reflect_dom_object;
 use crate::dom::bindings::root::{DomRoot, MutDom};
 use crate::dom::dompointreadonly::DOMPointReadOnly;
@@ -11,7 +12,10 @@ use crate::dom::window::Window;
 use crate::dom::xrrigidtransform::XRRigidTransform;
 use crate::dom::xrsession::XRSession;
 use crate::dom::xrspace::XRSpace;
+use crate::dom::xrstationaryreferencespace::XRStationaryReferenceSpace;
 use dom_struct::dom_struct;
+use euclid::Transform3D;
+use webvr_traits::WebVRFrameData;
 
 #[dom_struct]
 pub struct XRReferenceSpace {
@@ -64,3 +68,33 @@ impl XRReferenceSpaceMethods for XRReferenceSpace {
         self.transform.get()
     }
 }
+
+impl XRReferenceSpace {
+    /// Gets viewer pose represented by this space
+    pub fn get_viewer_pose(&self, base_pose: &WebVRFrameData) -> Transform3D<f64> {
+        let pose = self.get_pose(base_pose);
+
+        // This may change, see https://github.com/immersive-web/webxr/issues/567
+        let offset = self.transform.get().matrix();
+        // XXXManishearth we can directly compute the inverse from the transform parameters
+        // (and perhaps cache it)
+        // XXXManishearth we can also optimize for the unset/identity offset case
+        let inverse = offset
+            .inverse()
+            .expect("rigid transforms are always invertible");
+        inverse.pre_mul(&pose)
+    }
+
+    /// Gets pose represented by this space
+    ///
+    /// Does not apply originOffset, use get_viewer_pose instead if you need it
+    pub fn get_pose(&self, base_pose: &WebVRFrameData) -> Transform3D<f64> {
+        if let Some(stationary) = self.downcast::<XRStationaryReferenceSpace>() {
+            stationary.get_pose(base_pose)
+        } else {
+            // non-subclassed XRReferenceSpaces exist, obtained via the "identity"
+            // type. The pose does not depend on the base pose.
+            Transform3D::identity()
+        }
+    }
+}

components/script/dom/xrrigidtransform.rs

@@ -3,6 +3,7 @@
  * 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::DOMPointReadOnlyBinding::DOMPointReadOnlyBinding::DOMPointReadOnlyMethods;
 use crate::dom::bindings::codegen::Bindings::XRRigidTransformBinding;
 use crate::dom::bindings::codegen::Bindings::XRRigidTransformBinding::XRRigidTransformMethods;
 use crate::dom::bindings::error::Fallible;
@@ -12,12 +13,17 @@ use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::dompointreadonly::DOMPointReadOnly;
 use crate::dom::window::Window;
 use dom_struct::dom_struct;
+use euclid::{Rotation3D, Transform3D};
 
 #[dom_struct]
 pub struct XRRigidTransform {
     reflector_: Reflector,
     position: Dom<DOMPointReadOnly>,
     orientation: Dom<DOMPointReadOnly>,
+    #[ignore_malloc_size_of = "defined in euclid"]
+    translate: Transform3D<f64>,
+    #[ignore_malloc_size_of = "defined in euclid"]
+    rotate: Rotation3D<f64>,
 }
 
 impl XRRigidTransform {
@@ -25,10 +31,23 @@ impl XRRigidTransform {
         position: &DOMPointReadOnly,
         orientation: &DOMPointReadOnly,
     ) -> XRRigidTransform {
+        let translate = Transform3D::create_translation(
+            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,
+        );
         XRRigidTransform {
             reflector_: Reflector::new(),
             position: Dom::from_ref(position),
             orientation: Dom::from_ref(orientation),
+            translate,
+            rotate,
         }
     }
 
@@ -65,6 +84,7 @@ impl XRRigidTransform {
     ) -> Fallible<DomRoot<Self>> {
         let global = window.global();
         let position = DOMPointReadOnly::new_from_init(&global, &position);
+        // XXXManishearth normalize this
         let orientation = DOMPointReadOnly::new_from_init(&global, &orientation);
         Ok(XRRigidTransform::new(window, &position, &orientation))
     }
@@ -79,4 +99,48 @@ impl XRRigidTransformMethods for XRRigidTransform {
     fn Orientation(&self) -> DomRoot<DOMPointReadOnly> {
         DomRoot::from_ref(&self.orientation)
     }
+    // https://immersive-web.github.io/webxr/#dom-xrrigidtransform-inverse
+    fn Inverse(&self) -> DomRoot<XRRigidTransform> {
+        // An XRRigidTransform is a rotation and a translation,
+        // i.e. T * R
+        //
+        // Its inverse is (T * R)^-1
+        //    = R^-1 * T^-1
+        //    = R^-1 * T^-1 * (R * R^-1)
+        //    = (R^-1 * T^-1 * R) * R^-1
+        //    = T' * R^-1
+        //    = T' * R'
+        //
+        //  (R^-1 * T^-1 * R) is a translation matrix, and R^-1 is a
+        //  rotation matrix, so we can use these in the new rigid transform
+        let r_1 = self.rotate.inverse();
+        let t_1 = self
+            .translate
+            .inverse()
+            .expect("translation matrices should be invertible");
+        let t_p = r_1
+            .to_transform()
+            .post_mul(&t_1)
+            .post_mul(&self.rotate.to_transform());
+
+        let global = self.global();
+        let position =
+            DOMPointReadOnly::new(&global, t_p.m41.into(), t_p.m42.into(), t_p.m43.into(), 1.);
+        let orientation = DOMPointReadOnly::new(
+            &global,
+            r_1.i.into(),
+            r_1.j.into(),
+            r_1.k.into(),
+            r_1.r.into(),
+        );
+        XRRigidTransform::new(global.as_window(), &position, &orientation)
+    }
+}
+
+impl XRRigidTransform {
+    pub fn matrix(&self) -> Transform3D<f64> {
+        // Spec says the orientation applies first,
+        // so post-multiply (?)
+        self.translate.post_mul(&self.rotate.to_transform())
+    }
 }

components/script/dom/xrsession.rs

@@ -56,6 +56,10 @@ impl XRSession {
         self.display.xr_present(self, None, Some(p));
     }
 
+    pub fn display(&self) -> &VRDisplay {
+        &self.display
+    }
+
     pub fn set_layer(&self, layer: &XRLayer) {
         self.base_layer.set(Some(layer))
     }

components/script/dom/xrspace.rs

@@ -3,12 +3,16 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use crate::dom::bindings::codegen::Bindings::XRSpaceBinding;
+use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::reflector::reflect_dom_object;
 use crate::dom::bindings::root::{Dom, DomRoot};
 use crate::dom::eventtarget::EventTarget;
 use crate::dom::globalscope::GlobalScope;
+use crate::dom::xrreferencespace::XRReferenceSpace;
 use crate::dom::xrsession::XRSession;
 use dom_struct::dom_struct;
+use euclid::Transform3D;
+use webvr_traits::WebVRFrameData;
 
 #[dom_struct]
 pub struct XRSpace {
@@ -33,3 +37,27 @@ impl XRSpace {
         )
     }
 }
+
+impl XRSpace {
+    /// Gets viewer pose represented by this space
+    #[allow(unused)]
+    pub fn get_viewer_pose(&self, base_pose: &WebVRFrameData) -> Transform3D<f64> {
+        if let Some(reference) = self.downcast::<XRReferenceSpace>() {
+            reference.get_viewer_pose(base_pose)
+        } else {
+            unreachable!()
+        }
+    }
+
+    /// Gets pose represented by this space
+    ///
+    /// Does not apply originOffset, use get_viewer_pose instead if you need it
+    #[allow(unused)]
+    pub fn get_pose(&self, base_pose: &WebVRFrameData) -> Transform3D<f64> {
+        if let Some(reference) = self.downcast::<XRReferenceSpace>() {
+            reference.get_pose(base_pose)
+        } else {
+            unreachable!()
+        }
+    }
+}

components/script/dom/xrstationaryreferencespace.rs

@@ -11,6 +11,8 @@ use crate::dom::xrreferencespace::XRReferenceSpace;
 use crate::dom::xrrigidtransform::XRRigidTransform;
 use crate::dom::xrsession::XRSession;
 use dom_struct::dom_struct;
+use euclid::{Rotation3D, Transform3D};
+use webvr_traits::WebVRFrameData;
 
 #[dom_struct]
 pub struct XRStationaryReferenceSpace {
@@ -46,3 +48,23 @@ impl XRStationaryReferenceSpace {
         )
     }
 }
+
+impl XRStationaryReferenceSpace {
+    /// Gets pose represented by this space
+    ///
+    /// Does not apply originOffset, use get_viewer_pose instead
+    pub fn get_pose(&self, base_pose: &WebVRFrameData) -> Transform3D<f64> {
+        // XXXManishearth add floor-level transform for floor-level and disable position in position-disabled
+        let pos = base_pose.pose.position.unwrap_or([0., 0., 0.]);
+        let translation =
+            Transform3D::create_translation(pos[0] as f64, pos[1] as f64, pos[2] as f64);
+        let orient = base_pose.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,
+        );
+        translation.pre_mul(&rotation.to_transform())
+    }
+}

components/script/dom/xrview.rs

@@ -10,6 +10,7 @@ use crate::dom::globalscope::GlobalScope;
 use crate::dom::vrframedata::create_typed_array;
 use crate::dom::xrsession::XRSession;
 use dom_struct::dom_struct;
+use euclid::Transform3D;
 use js::jsapi::{Heap, JSContext, JSObject};
 use std::ptr::NonNull;
 use webvr_traits::WebVRFrameData;
@@ -39,6 +40,7 @@ impl XRView {
         global: &GlobalScope,
         session: &XRSession,
         eye: XREye,
+        pose: &Transform3D<f64>,
         data: &WebVRFrameData,
     ) -> DomRoot<XRView> {
         let ret = reflect_dom_object(
@@ -47,16 +49,29 @@ impl XRView {
             XRViewBinding::Wrap,
         );
 
-        let (proj, view) = if eye == XREye::Left {
-            (&data.left_projection_matrix, &data.left_view_matrix)
+        let vr_display = session.display();
+
+        // XXXManishearth compute and cache projection matrices on the Display
+        let (proj, offset) = if eye == XREye::Left {
+            (
+                &data.left_projection_matrix,
+                vr_display.left_eye_params_offset(),
+            )
         } else {
-            (&data.right_projection_matrix, &data.right_view_matrix)
+            (
+                &data.right_projection_matrix,
+                vr_display.right_eye_params_offset(),
+            )
         };
 
+        let offset =
+            Transform3D::create_translation(offset[0] as f64, offset[1] as f64, offset[2] as f64);
+        let view = pose.post_mul(&offset).cast().to_column_major_array();
+
         let cx = global.get_cx();
         unsafe {
             create_typed_array(cx, proj, &ret.proj);
-            create_typed_array(cx, view, &ret.view);
+            create_typed_array(cx, &view, &ret.view);
         }
         ret
     }

components/script/dom/xrviewport.rs

@@ -57,7 +57,7 @@ impl XRViewportMethods for XRViewport {
 
     /// https://immersive-web.github.io/webxr/#dom-xrviewport-width
     fn Width(&self) -> i32 {
-        self.height as i32
+        self.width as i32
     }
 
     /// https://immersive-web.github.io/webxr/#dom-xrviewport-height