script/dom/webxr/
xrsession.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::cell::Cell;
6use std::collections::HashMap;
7use std::f64::consts::{FRAC_PI_2, PI};
8use std::rc::Rc;
9use std::{mem, ptr};
10
11use script_bindings::reflector::reflect_dom_object_with_cx;
12use servo_base::cross_process_instant::CrossProcessInstant;
13use dom_struct::dom_struct;
14use js::context::JSContext;
15use js::realm::CurrentRealm;
16use euclid::{RigidTransform3D, Transform3D, Vector3D};
17use ipc_channel::ipc::IpcReceiver;
18use ipc_channel::router::ROUTER;
19use js::jsapi::JSObject;
20use js::rust::MutableHandleValue;
21use js::typedarray::HeapFloat32Array;
22use profile_traits::generic_callback::GenericCallback as ProfileGenericCallback;
23use rustc_hash::FxBuildHasher;
24use script_bindings::trace::RootedTraceableBox;
25use stylo_atoms::Atom;
26use webxr_api::{
27    self, ApiSpace, ContextId as WebXRContextId, Display, EntityTypes, EnvironmentBlendMode,
28    Event as XREvent, Frame, FrameUpdateEvent, HitTestId, HitTestSource, InputFrame, InputId, Ray,
29    SelectEvent, SelectKind, Session, SessionId, View, Viewer, Visibility, util,
30};
31
32use crate::conversions::Convert;
33use crate::canvas_context::CanvasContext;
34use crate::dom::bindings::trace::HashMapTracedValues;
35use crate::dom::bindings::buffer_source::create_buffer_source;
36use crate::dom::bindings::callback::ExceptionHandling;
37use script_bindings::cell::DomRefCell;
38use crate::dom::bindings::codegen::Bindings::NavigatorBinding::Navigator_Binding::NavigatorMethods;
39use crate::dom::bindings::codegen::Bindings::WindowBinding::Window_Binding::WindowMethods;
40use crate::dom::bindings::codegen::Bindings::XRHitTestSourceBinding::{
41    XRHitTestOptionsInit, XRHitTestTrackableType,
42};
43use crate::dom::bindings::codegen::Bindings::XRInputSourceArrayBinding::XRInputSourceArray_Binding::XRInputSourceArrayMethods;
44use crate::dom::bindings::codegen::Bindings::XRReferenceSpaceBinding::XRReferenceSpaceType;
45use crate::dom::bindings::codegen::Bindings::XRRenderStateBinding::{
46    XRRenderStateInit, XRRenderStateMethods,
47};
48use crate::dom::bindings::codegen::Bindings::XRSessionBinding::{
49    XREnvironmentBlendMode, XRFrameRequestCallback, XRInteractionMode, XRSessionMethods,
50    XRVisibilityState,
51};
52use crate::dom::bindings::codegen::Bindings::XRSystemBinding::XRSessionMode;
53use crate::dom::bindings::error::{Error, ErrorResult};
54use crate::dom::bindings::inheritance::Castable;
55use crate::dom::bindings::num::Finite;
56use crate::dom::bindings::refcounted::Trusted;
57use crate::dom::bindings::reflector::{DomGlobal};
58use crate::dom::bindings::root::{Dom, DomRoot, MutDom, MutNullableDom};
59use crate::dom::bindings::utils::to_frozen_array;
60use crate::dom::event::Event;
61use crate::dom::eventtarget::EventTarget;
62use crate::dom::promise::Promise;
63use crate::dom::window::Window;
64use crate::dom::xrboundedreferencespace::XRBoundedReferenceSpace;
65use crate::dom::xrframe::XRFrame;
66use crate::dom::xrhittestsource::XRHitTestSource;
67use crate::dom::xrinputsourcearray::XRInputSourceArray;
68use crate::dom::xrinputsourceevent::XRInputSourceEvent;
69use crate::dom::xrreferencespace::XRReferenceSpace;
70use crate::dom::xrreferencespaceevent::XRReferenceSpaceEvent;
71use crate::dom::xrrenderstate::XRRenderState;
72use crate::dom::xrrigidtransform::XRRigidTransform;
73use crate::dom::xrsessionevent::XRSessionEvent;
74use crate::dom::xrspace::XRSpace;
75
76#[dom_struct]
77pub(crate) struct XRSession {
78    eventtarget: EventTarget,
79    blend_mode: XREnvironmentBlendMode,
80    mode: XRSessionMode,
81    visibility_state: Cell<XRVisibilityState>,
82    viewer_space: MutNullableDom<XRSpace>,
83    #[no_trace]
84    session: DomRefCell<Session>,
85    frame_requested: Cell<bool>,
86    pending_render_state: MutNullableDom<XRRenderState>,
87    active_render_state: MutDom<XRRenderState>,
88    /// Cached projection matrix for inline sessions
89    #[no_trace]
90    inline_projection_matrix: DomRefCell<Transform3D<f32, Viewer, Display>>,
91
92    next_raf_id: Cell<i32>,
93    #[ignore_malloc_size_of = "closures are hard"]
94    raf_callback_list: DomRefCell<Vec<(i32, Option<Rc<XRFrameRequestCallback>>)>>,
95    #[ignore_malloc_size_of = "closures are hard"]
96    current_raf_callback_list: DomRefCell<Vec<(i32, Option<Rc<XRFrameRequestCallback>>)>>,
97    input_sources: Dom<XRInputSourceArray>,
98    // Any promises from calling end()
99    #[conditional_malloc_size_of]
100    end_promises: DomRefCell<Vec<Rc<Promise>>>,
101    /// <https://immersive-web.github.io/webxr/#ended>
102    ended: Cell<bool>,
103    #[no_trace]
104    next_hit_test_id: Cell<HitTestId>,
105    #[ignore_malloc_size_of = "Promise"]
106    pending_hit_test_promises:
107        DomRefCell<HashMapTracedValues<HitTestId, Rc<Promise>, FxBuildHasher>>,
108    /// Opaque framebuffers need to know the session is "outside of a requestAnimationFrame"
109    /// <https://immersive-web.github.io/webxr/#opaque-framebuffer>
110    outside_raf: Cell<bool>,
111    #[no_trace]
112    input_frames: DomRefCell<HashMap<InputId, InputFrame>>,
113    framerate: Cell<f32>,
114    #[conditional_malloc_size_of]
115    update_framerate_promise: DomRefCell<Option<Rc<Promise>>>,
116    reference_spaces: DomRefCell<Vec<Dom<XRReferenceSpace>>>,
117}
118
119impl XRSession {
120    fn new_inherited(
121        session: Session,
122        render_state: &XRRenderState,
123        input_sources: &XRInputSourceArray,
124        mode: XRSessionMode,
125    ) -> XRSession {
126        XRSession {
127            eventtarget: EventTarget::new_inherited(),
128            blend_mode: session.environment_blend_mode().convert(),
129            mode,
130            visibility_state: Cell::new(XRVisibilityState::Visible),
131            viewer_space: Default::default(),
132            session: DomRefCell::new(session),
133            frame_requested: Cell::new(false),
134            pending_render_state: MutNullableDom::new(None),
135            active_render_state: MutDom::new(render_state),
136            inline_projection_matrix: Default::default(),
137
138            next_raf_id: Cell::new(0),
139            raf_callback_list: DomRefCell::new(vec![]),
140            current_raf_callback_list: DomRefCell::new(vec![]),
141            input_sources: Dom::from_ref(input_sources),
142            end_promises: DomRefCell::new(vec![]),
143            ended: Cell::new(false),
144            next_hit_test_id: Cell::new(HitTestId(0)),
145            pending_hit_test_promises: DomRefCell::new(HashMapTracedValues::new_fx()),
146            outside_raf: Cell::new(true),
147            input_frames: DomRefCell::new(HashMap::new()),
148            framerate: Cell::new(0.0),
149            update_framerate_promise: DomRefCell::new(None),
150            reference_spaces: DomRefCell::new(Vec::new()),
151        }
152    }
153
154    pub(crate) fn new(
155        cx: &mut JSContext,
156        window: &Window,
157        session: Session,
158        mode: XRSessionMode,
159        frame_receiver: IpcReceiver<Frame>,
160    ) -> DomRoot<XRSession> {
161        let ivfov = if mode == XRSessionMode::Inline {
162            Some(FRAC_PI_2)
163        } else {
164            None
165        };
166        let render_state = XRRenderState::new(cx, window, 0.1, 1000.0, ivfov, None, Vec::new());
167        let input_sources = XRInputSourceArray::new(cx, window);
168        let ret = reflect_dom_object_with_cx(
169            Box::new(XRSession::new_inherited(
170                session,
171                &render_state,
172                &input_sources,
173                mode,
174            )),
175            window,
176            cx,
177        );
178        ret.attach_event_handler();
179        ret.setup_raf_loop(frame_receiver);
180        ret
181    }
182
183    pub(crate) fn with_session<R, F: FnOnce(&Session) -> R>(&self, with: F) -> R {
184        let session = self.session.borrow();
185        with(&session)
186    }
187
188    pub(crate) fn is_ended(&self) -> bool {
189        self.ended.get()
190    }
191
192    pub(crate) fn is_immersive(&self) -> bool {
193        self.mode != XRSessionMode::Inline
194    }
195
196    // https://immersive-web.github.io/layers/#feature-descriptor-layers
197    pub(crate) fn has_layers_feature(&self) -> bool {
198        // We do not support creating layers other than projection layers
199        // https://github.com/servo/servo/issues/27493
200        false
201    }
202
203    fn setup_raf_loop(&self, frame_receiver: IpcReceiver<Frame>) {
204        let this = Trusted::new(self);
205        let global = self.global();
206        let task_source = global
207            .task_manager()
208            .dom_manipulation_task_source()
209            .to_sendable();
210        ROUTER.add_typed_route(
211            frame_receiver,
212            Box::new(move |message| {
213                let frame: Frame = message.unwrap();
214                let time = CrossProcessInstant::now();
215                let this = this.clone();
216                task_source.queue(task!(xr_raf_callback: move |cx| {
217                    this.root().raf_callback(cx, frame, time);
218                }));
219            }),
220        );
221
222        self.session.borrow_mut().start_render_loop();
223    }
224
225    pub(crate) fn is_outside_raf(&self) -> bool {
226        self.outside_raf.get()
227    }
228
229    fn attach_event_handler(&self) {
230        let this = Trusted::new(self);
231        let global = self.global();
232        let task_source = global
233            .task_manager()
234            .dom_manipulation_task_source()
235            .to_sendable();
236        let callback =
237            ProfileGenericCallback::new(global.time_profiler_chan().clone(), move |message| {
238                let this = this.clone();
239                task_source.queue(task!(xr_event_callback: move |cx| {
240                    this.root().event_callback(cx, message.unwrap());
241                }))
242            })
243            .expect("Could not create callback");
244
245        // request animation frame
246        self.session.borrow_mut().set_event_dest(callback);
247    }
248
249    // Must be called after the promise for session creation is resolved
250    // https://github.com/immersive-web/webxr/issues/961
251    //
252    // This enables content that assumes all input sources are accompanied
253    // by an inputsourceschange event to work properly. Without
254    pub(crate) fn setup_initial_inputs(&self) {
255        let initial_inputs = self.session.borrow().initial_inputs().to_owned();
256
257        if initial_inputs.is_empty() {
258            // do not fire an empty event
259            return;
260        }
261
262        let this = Trusted::new(self);
263        // Queue a task so that it runs after resolve()'s microtasks complete
264        // so that content has a chance to attach a listener for inputsourceschange
265        self.global()
266            .task_manager()
267            .dom_manipulation_task_source()
268            .queue(task!(session_initial_inputs: move |cx| {
269                let this = this.root();
270                this.input_sources.add_input_sources(cx, &this, &initial_inputs);
271            }));
272    }
273
274    fn event_callback(&self, cx: &mut JSContext, event: XREvent) {
275        match event {
276            XREvent::SessionEnd => {
277                // https://immersive-web.github.io/webxr/#shut-down-the-session
278                // Step 2
279                self.ended.set(true);
280                // Step 3-4
281                self.global()
282                    .as_window()
283                    .Navigator()
284                    .Xr(cx)
285                    .end_session(self);
286                // Step 5: We currently do not have any such promises
287                // Step 6 is happening n the XR session
288                // https://immersive-web.github.io/webxr/#dom-xrsession-end step 3
289                for promise in self.end_promises.borrow_mut().drain(..) {
290                    promise.resolve_native(cx, &());
291                }
292                // Step 7
293                let event = XRSessionEvent::new(
294                    cx,
295                    self.global().as_window(),
296                    atom!("end"),
297                    false,
298                    false,
299                    self,
300                );
301                event.upcast::<Event>().fire(cx, self.upcast());
302            },
303            XREvent::Select(input, kind, ty, frame) => {
304                use stylo_atoms::Atom;
305                const START_ATOMS: [Atom; 2] = [atom!("selectstart"), atom!("squeezestart")];
306                const EVENT_ATOMS: [Atom; 2] = [atom!("select"), atom!("squeeze")];
307                const END_ATOMS: [Atom; 2] = [atom!("selectend"), atom!("squeezeend")];
308
309                // https://immersive-web.github.io/webxr/#primary-action
310                let source = self.input_sources.find(input);
311                let atom_index = if kind == SelectKind::Squeeze { 1 } else { 0 };
312                if let Some(source) = source {
313                    let frame = XRFrame::new(cx, self.global().as_window(), self, frame);
314                    frame.set_active(true);
315                    if ty == SelectEvent::Start {
316                        let event = XRInputSourceEvent::new(
317                            cx,
318                            self.global().as_window(),
319                            START_ATOMS[atom_index].clone(),
320                            false,
321                            false,
322                            &frame,
323                            &source,
324                        );
325                        event.upcast::<Event>().fire(cx, self.upcast());
326                    } else {
327                        if ty == SelectEvent::Select {
328                            let event = XRInputSourceEvent::new(
329                                cx,
330                                self.global().as_window(),
331                                EVENT_ATOMS[atom_index].clone(),
332                                false,
333                                false,
334                                &frame,
335                                &source,
336                            );
337                            event.upcast::<Event>().fire(cx, self.upcast());
338                        }
339                        let event = XRInputSourceEvent::new(
340                            cx,
341                            self.global().as_window(),
342                            END_ATOMS[atom_index].clone(),
343                            false,
344                            false,
345                            &frame,
346                            &source,
347                        );
348                        event.upcast::<Event>().fire(cx, self.upcast());
349                    }
350                    frame.set_active(false);
351                }
352            },
353            XREvent::VisibilityChange(v) => {
354                let v = match v {
355                    Visibility::Visible => XRVisibilityState::Visible,
356                    Visibility::VisibleBlurred => XRVisibilityState::Visible_blurred,
357                    Visibility::Hidden => XRVisibilityState::Hidden,
358                };
359                self.visibility_state.set(v);
360                let event = XRSessionEvent::new(
361                    cx,
362                    self.global().as_window(),
363                    atom!("visibilitychange"),
364                    false,
365                    false,
366                    self,
367                );
368                event.upcast::<Event>().fire(cx, self.upcast());
369                // The page may be visible again, dirty the layers
370                // This also wakes up the event loop if necessary
371                self.dirty_layers();
372            },
373            XREvent::AddInput(info) => {
374                self.input_sources.add_input_sources(cx, self, &[info]);
375            },
376            XREvent::RemoveInput(id) => {
377                self.input_sources.remove_input_source(cx, self, id);
378            },
379            XREvent::UpdateInput(id, source) => {
380                self.input_sources
381                    .add_remove_input_source(cx, self, id, source);
382            },
383            XREvent::InputChanged(id, frame) => {
384                self.input_frames.borrow_mut().insert(id, frame);
385            },
386            XREvent::ReferenceSpaceChanged(base_space, transform) => {
387                self.reference_spaces
388                    .borrow()
389                    .iter()
390                    .filter(|space| {
391                        let base = match space.ty() {
392                            XRReferenceSpaceType::Local => webxr_api::BaseSpace::Local,
393                            XRReferenceSpaceType::Viewer => webxr_api::BaseSpace::Viewer,
394                            XRReferenceSpaceType::Local_floor => webxr_api::BaseSpace::Floor,
395                            XRReferenceSpaceType::Bounded_floor => {
396                                webxr_api::BaseSpace::BoundedFloor
397                            },
398                            _ => panic!("unsupported reference space found"),
399                        };
400                        base == base_space
401                    })
402                    .for_each(|space| {
403                        let offset =
404                            XRRigidTransform::new(cx, self.global().as_window(), transform);
405                        let event = XRReferenceSpaceEvent::new(
406                            cx,
407                            self.global().as_window(),
408                            atom!("reset"),
409                            false,
410                            false,
411                            space,
412                            Some(&*offset),
413                        );
414                        event.upcast::<Event>().fire(cx, space.upcast());
415                    });
416            },
417        }
418    }
419
420    /// <https://immersive-web.github.io/webxr/#xr-animation-frame>
421    fn raf_callback(&self, cx: &mut JSContext, mut frame: Frame, time: CrossProcessInstant) {
422        debug!("WebXR RAF callback {:?}", frame);
423
424        // Step 1-2 happen in the xebxr device thread
425
426        // Step 3
427        if let Some(pending) = self.pending_render_state.take() {
428            // https://immersive-web.github.io/webxr/#apply-the-pending-render-state
429            // (Steps 1-4 are implicit)
430            // Step 5
431            self.active_render_state.set(&pending);
432            // Step 6-7: XXXManishearth handle inlineVerticalFieldOfView
433
434            if !self.is_immersive() {
435                self.update_inline_projection_matrix()
436            }
437        }
438
439        // TODO: how does this fit the webxr spec?
440        for event in frame.events.drain(..) {
441            self.handle_frame_event(cx, event);
442        }
443
444        // Step 4
445        // TODO: what should this check be?
446        // This is checking that the new render state has the same
447        // layers as the frame.
448        // Related to https://github.com/immersive-web/webxr/issues/1051
449        if !self
450            .active_render_state
451            .get()
452            .has_sub_images(&frame.sub_images[..])
453        {
454            // If the frame has different layers than the render state,
455            // we just return early, drawing a blank frame.
456            // This can result in flickering when the render state is changed.
457            // TODO: it would be better to not render anything until the next frame.
458            warn!("Rendering blank XR frame");
459            self.session.borrow_mut().render_animation_frame();
460            return;
461        }
462
463        // Step 5: XXXManishearth handle inline session
464
465        // Step 6-7
466        {
467            let mut current = self.current_raf_callback_list.borrow_mut();
468            assert!(current.is_empty());
469            mem::swap(&mut *self.raf_callback_list.borrow_mut(), &mut current);
470        }
471
472        let time = self.global().performance().to_dom_high_res_time_stamp(time);
473        let frame = XRFrame::new(cx, self.global().as_window(), self, frame);
474
475        // Step 8-9
476        frame.set_active(true);
477        frame.set_animation_frame(true);
478
479        // Step 10
480        self.apply_frame_updates(&frame);
481
482        // TODO: how does this fit with the webxr and xr layers specs?
483        self.layers_begin_frame(cx, &frame);
484
485        // Step 11-12
486        self.outside_raf.set(false);
487        let len = self.current_raf_callback_list.borrow().len();
488        for i in 0..len {
489            let callback = self.current_raf_callback_list.borrow()[i].1.clone();
490            if let Some(callback) = callback {
491                let _ = callback.Call__(cx, time, &frame, ExceptionHandling::Report);
492            }
493        }
494        self.outside_raf.set(true);
495        *self.current_raf_callback_list.borrow_mut() = vec![];
496
497        // TODO: how does this fit with the webxr and xr layers specs?
498        self.layers_end_frame(&frame);
499
500        // Step 13
501        frame.set_active(false);
502
503        // TODO: how does this fit the webxr spec?
504        self.session.borrow_mut().render_animation_frame();
505    }
506
507    fn update_inline_projection_matrix(&self) {
508        debug_assert!(!self.is_immersive());
509        let render_state = self.active_render_state.get();
510        let size = if let Some(base) = render_state.GetBaseLayer() {
511            base.size()
512        } else {
513            return;
514        };
515        let mut clip_planes = util::ClipPlanes::default();
516        let near = *render_state.DepthNear() as f32;
517        let far = *render_state.DepthFar() as f32;
518        clip_planes.update(near, far);
519        let top = *render_state
520            .GetInlineVerticalFieldOfView()
521            .expect("IVFOV should be non null for inline sessions") /
522            2.;
523        let top = near * top.tan() as f32;
524        let bottom = top;
525        let left = top * size.width as f32 / size.height as f32;
526        let right = left;
527        let matrix = util::frustum_to_projection_matrix(left, right, top, bottom, clip_planes);
528        *self.inline_projection_matrix.borrow_mut() = matrix;
529    }
530
531    /// Constructs a View suitable for inline sessions using the inlineVerticalFieldOfView and canvas size
532    pub(crate) fn inline_view(&self) -> View<Viewer> {
533        debug_assert!(!self.is_immersive());
534        View {
535            // Inline views have no offset
536            transform: RigidTransform3D::identity(),
537            projection: *self.inline_projection_matrix.borrow(),
538        }
539    }
540
541    pub(crate) fn session_id(&self) -> SessionId {
542        self.session.borrow().id()
543    }
544
545    pub(crate) fn dirty_layers(&self) {
546        if let Some(layer) = self.RenderState().GetBaseLayer() {
547            layer.context().mark_as_dirty();
548        }
549    }
550
551    // TODO: how does this align with the layers spec?
552    fn layers_begin_frame(&self, cx: &mut JSContext, frame: &XRFrame) {
553        if let Some(layer) = self.active_render_state.get().GetBaseLayer() {
554            layer.begin_frame(cx, frame);
555        }
556        self.active_render_state.get().with_layers(|layers| {
557            for layer in layers {
558                layer.begin_frame(cx, frame);
559            }
560        });
561    }
562
563    // TODO: how does this align with the layers spec?
564    fn layers_end_frame(&self, frame: &XRFrame) {
565        if let Some(layer) = self.active_render_state.get().GetBaseLayer() {
566            layer.end_frame(frame);
567        }
568        self.active_render_state.get().with_layers(|layers| {
569            for layer in layers {
570                layer.end_frame(frame);
571            }
572        });
573    }
574
575    /// <https://immersive-web.github.io/webxr/#xrframe-apply-frame-updates>
576    fn apply_frame_updates(&self, _frame: &XRFrame) {
577        // <https://www.w3.org/TR/webxr-gamepads-module-1/#xrframe-apply-gamepad-frame-updates>
578        for (id, frame) in self.input_frames.borrow_mut().drain() {
579            let source = self.input_sources.find(id);
580            if let Some(source) = source {
581                source.update_gamepad_state(frame);
582            }
583        }
584    }
585
586    fn handle_frame_event(&self, cx: &mut JSContext, event: FrameUpdateEvent) {
587        match event {
588            FrameUpdateEvent::HitTestSourceAdded(id) => {
589                if let Some(promise) = self.pending_hit_test_promises.borrow_mut().remove(&id) {
590                    let hit_test_source =
591                        XRHitTestSource::new(cx, self.global().as_window(), id, self);
592                    promise.resolve_native(cx, &hit_test_source);
593                } else {
594                    warn!(
595                        "received hit test add request for unknown hit test {:?}",
596                        id
597                    )
598                }
599            },
600            _ => self.session.borrow_mut().apply_event(event),
601        }
602    }
603
604    /// <https://www.w3.org/TR/webxr/#apply-the-nominal-frame-rate>
605    fn apply_nominal_framerate(&self, cx: &mut JSContext, rate: f32) {
606        if self.framerate.get() == rate || self.ended.get() {
607            return;
608        }
609
610        self.framerate.set(rate);
611
612        let event = XRSessionEvent::new(
613            cx,
614            self.global().as_window(),
615            Atom::from("frameratechange"),
616            false,
617            false,
618            self,
619        );
620        event.upcast::<Event>().fire(cx, self.upcast());
621    }
622}
623
624impl XRSessionMethods<crate::DomTypeHolder> for XRSession {
625    // https://immersive-web.github.io/webxr/#eventdef-xrsession-end
626    event_handler!(end, GetOnend, SetOnend);
627
628    // https://immersive-web.github.io/webxr/#eventdef-xrsession-select
629    event_handler!(select, GetOnselect, SetOnselect);
630
631    // https://immersive-web.github.io/webxr/#eventdef-xrsession-selectstart
632    event_handler!(selectstart, GetOnselectstart, SetOnselectstart);
633
634    // https://immersive-web.github.io/webxr/#eventdef-xrsession-selectend
635    event_handler!(selectend, GetOnselectend, SetOnselectend);
636
637    // https://immersive-web.github.io/webxr/#eventdef-xrsession-squeeze
638    event_handler!(squeeze, GetOnsqueeze, SetOnsqueeze);
639
640    // https://immersive-web.github.io/webxr/#eventdef-xrsession-squeezestart
641    event_handler!(squeezestart, GetOnsqueezestart, SetOnsqueezestart);
642
643    // https://immersive-web.github.io/webxr/#eventdef-xrsession-squeezeend
644    event_handler!(squeezeend, GetOnsqueezeend, SetOnsqueezeend);
645
646    // https://immersive-web.github.io/webxr/#eventdef-xrsession-visibilitychange
647    event_handler!(
648        visibilitychange,
649        GetOnvisibilitychange,
650        SetOnvisibilitychange
651    );
652
653    // https://immersive-web.github.io/webxr/#eventdef-xrsession-inputsourceschange
654    event_handler!(
655        inputsourceschange,
656        GetOninputsourceschange,
657        SetOninputsourceschange
658    );
659
660    // https://www.w3.org/TR/webxr/#dom-xrsession-onframeratechange
661    event_handler!(frameratechange, GetOnframeratechange, SetOnframeratechange);
662
663    /// <https://immersive-web.github.io/webxr/#dom-xrsession-renderstate>
664    fn RenderState(&self) -> DomRoot<XRRenderState> {
665        self.active_render_state.get()
666    }
667
668    /// <https://immersive-web.github.io/webxr/#dom-xrsession-updaterenderstate>
669    fn UpdateRenderState(&self, cx: &mut JSContext, init: &XRRenderStateInit) -> ErrorResult {
670        // Step 2
671        if self.ended.get() {
672            return Err(Error::InvalidState(None));
673        }
674        // Step 3:
675        if let Some(Some(ref layer)) = init.baseLayer &&
676            Dom::from_ref(layer.session()) != Dom::from_ref(self)
677        {
678            return Err(Error::InvalidState(None));
679        }
680
681        // Step 4:
682        if init.inlineVerticalFieldOfView.is_some() && self.is_immersive() {
683            return Err(Error::InvalidState(None));
684        }
685
686        // https://immersive-web.github.io/layers/#updaterenderstatechanges
687        // Step 1.
688        if init.baseLayer.is_some() && (self.has_layers_feature() || init.layers.is_some()) {
689            return Err(Error::NotSupported(None));
690        }
691
692        if let Some(Some(ref layers)) = init.layers {
693            // Step 2
694            for layer in layers {
695                let count = layers
696                    .iter()
697                    .filter(|other| other.layer_id() == layer.layer_id())
698                    .count();
699                if count > 1 {
700                    return Err(Error::Type(c"Duplicate entry in WebXR layers".to_owned()));
701                }
702            }
703
704            // Step 3
705            for layer in layers {
706                if layer.session() != self {
707                    return Err(Error::Type(
708                        c"Layer from different session in WebXR layers".to_owned(),
709                    ));
710                }
711            }
712        }
713
714        // Step 4-5
715        let pending = self
716            .pending_render_state
717            .or_init(|| self.active_render_state.get().clone_object(cx));
718
719        // Step 6
720        if let Some(ref layers) = init.layers {
721            let layers = layers.as_deref().unwrap_or_default();
722            pending.set_base_layer(None);
723            pending.set_layers(layers.iter().map(|x| &**x).collect());
724            let layers = layers
725                .iter()
726                .filter_map(|layer| {
727                    let context_id = WebXRContextId::from(layer.context_id());
728                    let layer_id = layer.layer_id()?;
729                    Some((context_id, layer_id))
730                })
731                .collect();
732            self.session.borrow_mut().set_layers(layers);
733        }
734
735        // End of https://immersive-web.github.io/layers/#updaterenderstatechanges
736
737        if let Some(near) = init.depthNear {
738            let mut near = *near;
739            // Step 8 from #apply-the-pending-render-state
740            // this may need to be changed if backends wish to impose
741            // further constraints
742            if near < 0. {
743                near = 0.;
744            }
745            pending.set_depth_near(near);
746        }
747        if let Some(far) = init.depthFar {
748            let mut far = *far;
749            // Step 9 from #apply-the-pending-render-state
750            // this may need to be changed if backends wish to impose
751            // further constraints
752            // currently the maximum is infinity, so just check that
753            // the value is non-negative
754            if far < 0. {
755                far = 0.;
756            }
757            pending.set_depth_far(far);
758        }
759        if let Some(fov) = init.inlineVerticalFieldOfView {
760            let mut fov = *fov;
761            // Step 10 from #apply-the-pending-render-state
762            // this may need to be changed if backends wish to impose
763            // further constraints
764            if fov < 0. {
765                fov = 0.0001;
766            } else if fov > PI {
767                fov = PI - 0.0001;
768            }
769            pending.set_inline_vertical_fov(fov);
770        }
771        if let Some(ref layer) = init.baseLayer {
772            pending.set_base_layer(layer.as_deref());
773            pending.set_layers(Vec::new());
774            let layers = layer
775                .iter()
776                .filter_map(|layer| {
777                    let context_id = WebXRContextId::from(layer.context_id());
778                    let layer_id = layer.layer_id()?;
779                    Some((context_id, layer_id))
780                })
781                .collect();
782            self.session.borrow_mut().set_layers(layers);
783        }
784
785        if init.depthFar.is_some() || init.depthNear.is_some() {
786            self.session
787                .borrow_mut()
788                .update_clip_planes(*pending.DepthNear() as f32, *pending.DepthFar() as f32);
789        }
790
791        Ok(())
792    }
793
794    /// <https://immersive-web.github.io/webxr/#dom-xrsession-requestanimationframe>
795    fn RequestAnimationFrame(&self, callback: Rc<XRFrameRequestCallback>) -> i32 {
796        // queue up RAF callback, obtain ID
797        let raf_id = self.next_raf_id.get();
798        self.next_raf_id.set(raf_id + 1);
799        self.raf_callback_list
800            .borrow_mut()
801            .push((raf_id, Some(callback)));
802
803        raf_id
804    }
805
806    /// <https://immersive-web.github.io/webxr/#dom-xrsession-cancelanimationframe>
807    fn CancelAnimationFrame(&self, frame: i32) {
808        let mut list = self.raf_callback_list.borrow_mut();
809        if let Some(pair) = list.iter_mut().find(|pair| pair.0 == frame) {
810            pair.1 = None;
811        }
812
813        let mut list = self.current_raf_callback_list.borrow_mut();
814        if let Some(pair) = list.iter_mut().find(|pair| pair.0 == frame) {
815            pair.1 = None;
816        }
817    }
818
819    /// <https://immersive-web.github.io/webxr/#dom-xrsession-environmentblendmode>
820    fn EnvironmentBlendMode(&self) -> XREnvironmentBlendMode {
821        self.blend_mode
822    }
823
824    /// <https://immersive-web.github.io/webxr/#dom-xrsession-visibilitystate>
825    fn VisibilityState(&self) -> XRVisibilityState {
826        self.visibility_state.get()
827    }
828
829    /// <https://immersive-web.github.io/webxr/#dom-xrsession-requestreferencespace>
830    fn RequestReferenceSpace(
831        &self,
832        cx: &mut CurrentRealm,
833        ty: XRReferenceSpaceType,
834    ) -> Rc<Promise> {
835        let p = Promise::new_in_realm(cx);
836
837        // https://immersive-web.github.io/webxr/#create-a-reference-space
838
839        // XXXManishearth reject based on session type
840        // https://github.com/immersive-web/webxr/blob/master/spatial-tracking-explainer.md#practical-usage-guidelines
841
842        if !self.is_immersive() &&
843            (ty == XRReferenceSpaceType::Bounded_floor || ty == XRReferenceSpaceType::Unbounded)
844        {
845            p.reject_error(cx, Error::NotSupported(None));
846            return p;
847        }
848
849        match ty {
850            XRReferenceSpaceType::Unbounded => {
851                // XXXmsub2 figure out how to support this
852                p.reject_error(cx, Error::NotSupported(None))
853            },
854            ty => {
855                if ty != XRReferenceSpaceType::Viewer &&
856                    (!self.is_immersive() || ty != XRReferenceSpaceType::Local)
857                {
858                    let s = ty.as_str();
859                    if !self
860                        .session
861                        .borrow()
862                        .granted_features()
863                        .iter()
864                        .any(|f| *f == s)
865                    {
866                        p.reject_error(cx, Error::NotSupported(None));
867                        return p;
868                    }
869                }
870                if ty == XRReferenceSpaceType::Bounded_floor {
871                    let space = XRBoundedReferenceSpace::new(cx, self.global().as_window(), self);
872                    self.reference_spaces
873                        .borrow_mut()
874                        .push(Dom::from_ref(space.reference_space()));
875                    p.resolve_native(cx, &space);
876                } else {
877                    let space = XRReferenceSpace::new(cx, self.global().as_window(), self, ty);
878                    self.reference_spaces
879                        .borrow_mut()
880                        .push(Dom::from_ref(&*space));
881                    p.resolve_native(cx, &space);
882                }
883            },
884        }
885        p
886    }
887
888    /// <https://immersive-web.github.io/webxr/#dom-xrsession-inputsources>
889    fn InputSources(&self) -> DomRoot<XRInputSourceArray> {
890        DomRoot::from_ref(&*self.input_sources)
891    }
892
893    /// <https://immersive-web.github.io/webxr/#dom-xrsession-end>
894    fn End(&self, cx: &mut CurrentRealm) -> Rc<Promise> {
895        let p = Promise::new_in_realm(cx);
896        if self.ended.get() && self.end_promises.borrow().is_empty() {
897            // If the session has completely ended and all end promises have been resolved,
898            // don't queue up more end promises
899            //
900            // We need to check for end_promises being empty because `ended` is set
901            // before everything has been completely shut down, and we do not want to
902            // prematurely resolve the promise then
903            //
904            // However, if end_promises is empty, then all end() promises have already resolved,
905            // so the session has completely shut down and we should not queue up more promises
906            p.resolve_native(cx, &());
907            return p;
908        }
909        self.end_promises.borrow_mut().push(p.clone());
910        // This is duplicated in event_callback since this should
911        // happen ASAP for end() but can happen later if the device
912        // shuts itself down
913        self.ended.set(true);
914        self.global()
915            .as_window()
916            .Navigator()
917            .Xr(cx)
918            .end_session(self);
919        self.session.borrow_mut().end_session();
920        // Disconnect any still-attached XRInputSources
921        for source in 0..self.input_sources.Length() {
922            self.input_sources
923                .remove_input_source(cx, self, InputId(source));
924        }
925        p
926    }
927
928    /// <https://immersive-web.github.io/hit-test/#dom-xrsession-requesthittestsource>
929    fn RequestHitTestSource(
930        &self,
931        cx: &mut CurrentRealm,
932        options: &XRHitTestOptionsInit,
933    ) -> Rc<Promise> {
934        let p = Promise::new_in_realm(cx);
935
936        if !self
937            .session
938            .borrow()
939            .granted_features()
940            .iter()
941            .any(|f| f == "hit-test")
942        {
943            p.reject_error(cx, Error::NotSupported(None));
944            return p;
945        }
946
947        let id = self.next_hit_test_id.get();
948        self.next_hit_test_id.set(HitTestId(id.0 + 1));
949
950        let space = options.space.space();
951        let ray = if let Some(ref ray) = options.offsetRay {
952            ray.ray()
953        } else {
954            Ray {
955                origin: Vector3D::new(0., 0., 0.),
956                direction: Vector3D::new(0., 0., -1.),
957            }
958        };
959
960        let mut types = EntityTypes::default();
961
962        if let Some(ref tys) = options.entityTypes {
963            for ty in tys {
964                match ty {
965                    XRHitTestTrackableType::Point => types.point = true,
966                    XRHitTestTrackableType::Plane => types.plane = true,
967                    XRHitTestTrackableType::Mesh => types.mesh = true,
968                }
969            }
970        } else {
971            types.plane = true;
972        }
973
974        let source = HitTestSource {
975            id,
976            space,
977            ray,
978            types,
979        };
980        self.pending_hit_test_promises
981            .borrow_mut()
982            .insert(id, p.clone());
983
984        self.session.borrow().request_hit_test(source);
985
986        p
987    }
988
989    /// <https://www.w3.org/TR/webxr-ar-module-1/#dom-xrsession-interactionmode>
990    fn InteractionMode(&self) -> XRInteractionMode {
991        // Until Servo supports WebXR sessions on mobile phones or similar non-XR devices,
992        // this should always be world space
993        XRInteractionMode::World_space
994    }
995
996    /// <https://www.w3.org/TR/webxr/#dom-xrsession-framerate>
997    fn GetFrameRate(&self) -> Option<Finite<f32>> {
998        let session = self.session.borrow();
999        if self.mode == XRSessionMode::Inline || session.supported_frame_rates().is_empty() {
1000            None
1001        } else {
1002            Finite::new(self.framerate.get())
1003        }
1004    }
1005
1006    /// <https://www.w3.org/TR/webxr/#dom-xrsession-supportedframerates>
1007    fn GetSupportedFrameRates(
1008        &self,
1009        cx: &mut JSContext,
1010    ) -> Option<RootedTraceableBox<HeapFloat32Array>> {
1011        let session = self.session.borrow();
1012        if self.mode == XRSessionMode::Inline || session.supported_frame_rates().is_empty() {
1013            None
1014        } else {
1015            let framerates = session.supported_frame_rates();
1016            rooted!(&in(cx) let mut array = ptr::null_mut::<JSObject>());
1017            Some(
1018                create_buffer_source(cx, framerates, array.handle_mut())
1019                    .expect("Failed to construct supported frame rates array"),
1020            )
1021        }
1022    }
1023
1024    /// <https://www.w3.org/TR/webxr/#dom-xrsession-enabledfeatures>
1025    fn EnabledFeatures(&self, cx: &mut JSContext, retval: MutableHandleValue) {
1026        let session = self.session.borrow();
1027        let features = session.granted_features();
1028        to_frozen_array(cx, features, retval)
1029    }
1030
1031    /// <https://www.w3.org/TR/webxr/#dom-xrsession-issystemkeyboardsupported>
1032    fn IsSystemKeyboardSupported(&self) -> bool {
1033        // Support for this only exists on Meta headsets (no desktop support)
1034        // so this will always be false until that changes
1035        false
1036    }
1037
1038    /// <https://www.w3.org/TR/webxr/#dom-xrsession-updatetargetframerate>
1039    fn UpdateTargetFrameRate(&self, cx: &mut CurrentRealm, rate: Finite<f32>) -> Rc<Promise> {
1040        let promise = Promise::new_in_realm(cx);
1041        {
1042            let session = self.session.borrow();
1043            let supported_frame_rates = session.supported_frame_rates();
1044
1045            if self.mode == XRSessionMode::Inline ||
1046                supported_frame_rates.is_empty() ||
1047                self.ended.get()
1048            {
1049                promise.reject_error(cx, Error::InvalidState(None));
1050                return promise;
1051            }
1052
1053            if !supported_frame_rates.contains(&*rate) {
1054                promise.reject_error(cx, Error::Type(c"Provided framerate not supported".into()));
1055                return promise;
1056            }
1057        }
1058
1059        *self.update_framerate_promise.borrow_mut() = Some(promise.clone());
1060
1061        let this = Trusted::new(self);
1062        let global = self.global();
1063        let task_source = global
1064            .task_manager()
1065            .dom_manipulation_task_source()
1066            .to_sendable();
1067
1068        let callback =
1069            ProfileGenericCallback::new(global.time_profiler_chan().clone(), move |message| {
1070                let this = this.clone();
1071                task_source.queue(task!(update_session_framerate: move |cx| {
1072                    let session = this.root();
1073                    session.apply_nominal_framerate(cx, message.unwrap());
1074                    if let Some(promise) = session.update_framerate_promise.borrow_mut().take() {
1075                        promise.resolve_native(cx, &());
1076                    };
1077                }));
1078            })
1079            .expect("Could not create callback");
1080
1081        self.session.borrow_mut().update_frame_rate(*rate, callback);
1082
1083        promise
1084    }
1085}
1086
1087// The pose of an object in native-space. Should never be exposed.
1088pub(crate) type ApiPose = RigidTransform3D<f32, ApiSpace, webxr_api::Native>;
1089// A transform between objects in some API-space
1090pub(crate) type ApiRigidTransform = RigidTransform3D<f32, ApiSpace, ApiSpace>;
1091
1092#[derive(Clone, Copy)]
1093pub(crate) struct BaseSpace;
1094
1095pub(crate) type BaseTransform = RigidTransform3D<f32, webxr_api::Native, BaseSpace>;
1096
1097#[expect(unsafe_code)]
1098pub(crate) fn cast_transform<T, U, V, W>(
1099    transform: RigidTransform3D<f32, T, U>,
1100) -> RigidTransform3D<f32, V, W> {
1101    unsafe { mem::transmute(transform) }
1102}
1103
1104impl Convert<XREnvironmentBlendMode> for EnvironmentBlendMode {
1105    fn convert(self) -> XREnvironmentBlendMode {
1106        match self {
1107            EnvironmentBlendMode::Opaque => XREnvironmentBlendMode::Opaque,
1108            EnvironmentBlendMode::AlphaBlend => XREnvironmentBlendMode::Alpha_blend,
1109            EnvironmentBlendMode::Additive => XREnvironmentBlendMode::Additive,
1110        }
1111    }
1112}
script/dom/webxr/xrsession.rs

script/dom/webxr/
xrsession.rs
