Auto merge of #24362 - Manishearth:input-selections, r=asajeffrey

Support input tracking loss and selection events in XR

Fixes https://github.com/servo/servo/issues/24192

Requires https://github.com/servo/webxr/pull/65

r? @jdm @asajeffrey

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7 files changed, 181 insertions, 9 deletions

diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index d6a6c30b823..598832403e0 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -549,6 +549,7 @@ pub mod xmlserializer;
 pub mod xr;
 pub mod xrframe;
 pub mod xrinputsource;
+pub mod xrinputsourceevent;
 pub mod xrpose;
 pub mod xrreferencespace;
 pub mod xrrenderstate;
diff --git a/components/script/dom/webidls/XRInputSourceEvent.webidl b/components/script/dom/webidls/XRInputSourceEvent.webidl
new file mode 100644
index 00000000000..f1ffbf2a799
--- /dev/null
+++ b/components/script/dom/webidls/XRInputSourceEvent.webidl
@@ -0,0 +1,17 @@
+/* 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/. */
+
+// https://immersive-web.github.io/webxr/#xrinputsourceevent-interface
+
+[SecureContext, Exposed=Window, Pref="dom.webxr.enabled"]
+interface XRInputSourceEvent : Event {
+  [Throws] constructor(DOMString type, XRInputSourceEventInit eventInitDict);
+  [SameObject] readonly attribute XRFrame frame;
+  [SameObject] readonly attribute XRInputSource inputSource;
+};
+
+dictionary XRInputSourceEventInit : EventInit {
+  required XRFrame frame;
+  required XRInputSource inputSource;
+};
diff --git a/components/script/dom/webidls/XRSession.webidl b/components/script/dom/webidls/XRSession.webidl
index 6d946ccef55..820ef11dc70 100644
--- a/components/script/dom/webidls/XRSession.webidl
+++ b/components/script/dom/webidls/XRSession.webidl
@@ -39,8 +39,8 @@ interface XRSession : EventTarget {
   // attribute EventHandler onblur;
   // attribute EventHandler onfocus;
   attribute EventHandler onend;
-  // attribute EventHandler onselect;
+  attribute EventHandler onselect;
   // attribute EventHandler oninputsourceschange;
-  // attribute EventHandler onselectstart;
-  // attribute EventHandler onselectend;
+  attribute EventHandler onselectstart;
+  attribute EventHandler onselectend;
 };
diff --git a/components/script/dom/xrframe.rs b/components/script/dom/xrframe.rs
index 29572c02300..6c67d896f81 100644
--- a/components/script/dom/xrframe.rs
+++ b/components/script/dom/xrframe.rs
@@ -93,8 +93,16 @@ impl XRFrameMethods for XRFrame {
         if !self.active.get() {
             return Err(Error::InvalidState);
         }
-        let space = space.get_pose(&self.data);
-        let relative_to = relative_to.get_pose(&self.data);
+        let space = if let Some(space) = space.get_pose(&self.data) {
+            space
+        } else {
+            return Ok(None);
+        };
+        let relative_to = if let Some(r) = relative_to.get_pose(&self.data) {
+            r
+        } else {
+            return Ok(None);
+        };
         let pose = relative_to.inverse().pre_transform(&space);
         Ok(Some(XRPose::new(&self.global(), pose)))
     }
diff --git a/components/script/dom/xrinputsourceevent.rs b/components/script/dom/xrinputsourceevent.rs
new file mode 100644
index 00000000000..aa177f1df9a
--- /dev/null
+++ b/components/script/dom/xrinputsourceevent.rs
@@ -0,0 +1,90 @@
+/* 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::EventBinding::EventBinding::EventMethods;
+use crate::dom::bindings::codegen::Bindings::XRInputSourceEventBinding::{
+    self, XRInputSourceEventMethods,
+};
+use crate::dom::bindings::error::Fallible;
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject};
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::event::Event;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::window::Window;
+use crate::dom::xrframe::XRFrame;
+use crate::dom::xrinputsource::XRInputSource;
+use dom_struct::dom_struct;
+use servo_atoms::Atom;
+
+#[dom_struct]
+pub struct XRInputSourceEvent {
+    event: Event,
+    frame: Dom<XRFrame>,
+    source: Dom<XRInputSource>,
+}
+
+impl XRInputSourceEvent {
+    #[allow(unrooted_must_root)]
+    fn new_inherited(frame: &XRFrame, source: &XRInputSource) -> XRInputSourceEvent {
+        XRInputSourceEvent {
+            event: Event::new_inherited(),
+            frame: Dom::from_ref(frame),
+            source: Dom::from_ref(source),
+        }
+    }
+
+    pub fn new(
+        global: &GlobalScope,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        frame: &XRFrame,
+        source: &XRInputSource,
+    ) -> DomRoot<XRInputSourceEvent> {
+        let trackevent = reflect_dom_object(
+            Box::new(XRInputSourceEvent::new_inherited(frame, source)),
+            global,
+            XRInputSourceEventBinding::Wrap,
+        );
+        {
+            let event = trackevent.upcast::<Event>();
+            event.init_event(type_, bubbles, cancelable);
+        }
+        trackevent
+    }
+
+    pub fn Constructor(
+        window: &Window,
+        type_: DOMString,
+        init: &XRInputSourceEventBinding::XRInputSourceEventInit,
+    ) -> Fallible<DomRoot<XRInputSourceEvent>> {
+        Ok(XRInputSourceEvent::new(
+            &window.global(),
+            Atom::from(type_),
+            init.parent.bubbles,
+            init.parent.cancelable,
+            &init.frame,
+            &init.inputSource,
+        ))
+    }
+}
+
+impl XRInputSourceEventMethods for XRInputSourceEvent {
+    // https://immersive-web.github.io/webxr/#dom-xrinputsourceeventinit-frame
+    fn Frame(&self) -> DomRoot<XRFrame> {
+        DomRoot::from_ref(&*self.frame)
+    }
+
+    // https://immersive-web.github.io/webxr/#dom-xrinputsourceeventinit-inputsource
+    fn InputSource(&self) -> DomRoot<XRInputSource> {
+        DomRoot::from_ref(&*self.source)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-event-istrusted
+    fn IsTrusted(&self) -> bool {
+        self.event.IsTrusted()
+    }
+}
diff --git a/components/script/dom/xrsession.rs b/components/script/dom/xrsession.rs
index dacfc373540..e7a3fab4677 100644
--- a/components/script/dom/xrsession.rs
+++ b/components/script/dom/xrsession.rs
@@ -33,6 +33,7 @@ use crate::dom::promise::Promise;
 use crate::dom::webglframebuffer::WebGLFramebufferAttachmentRoot;
 use crate::dom::xrframe::XRFrame;
 use crate::dom::xrinputsource::XRInputSource;
+use crate::dom::xrinputsourceevent::XRInputSourceEvent;
 use crate::dom::xrreferencespace::XRReferenceSpace;
 use crate::dom::xrrenderstate::XRRenderState;
 use crate::dom::xrsessionevent::XRSessionEvent;
@@ -48,7 +49,7 @@ use profile_traits::ipc;
 use std::cell::Cell;
 use std::mem;
 use std::rc::Rc;
-use webxr_api::{self, Event as XREvent, Frame, Session};
+use webxr_api::{self, Event as XREvent, Frame, SelectEvent, Session};
 
 #[dom_struct]
 pub struct XRSession {
@@ -170,6 +171,52 @@ impl XRSession {
                 let event = XRSessionEvent::new(&self.global(), atom!("end"), false, false, self);
                 event.upcast::<Event>().fire(self.upcast());
             },
+            XREvent::Select(input, kind, frame) => {
+                // https://immersive-web.github.io/webxr/#primary-action
+                let source = self
+                    .input_sources
+                    .borrow_mut()
+                    .iter()
+                    .find(|s| s.id() == input)
+                    .map(|x| DomRoot::from_ref(&**x));
+                if let Some(source) = source {
+                    let frame = XRFrame::new(&self.global(), self, frame);
+                    frame.set_active(true);
+                    if kind == SelectEvent::Start {
+                        let event = XRInputSourceEvent::new(
+                            &self.global(),
+                            atom!("selectstart"),
+                            false,
+                            false,
+                            &frame,
+                            &source,
+                        );
+                        event.upcast::<Event>().fire(self.upcast());
+                    } else {
+                        if kind == SelectEvent::Select {
+                            let event = XRInputSourceEvent::new(
+                                &self.global(),
+                                atom!("select"),
+                                false,
+                                false,
+                                &frame,
+                                &source,
+                            );
+                            event.upcast::<Event>().fire(self.upcast());
+                        }
+                        let event = XRInputSourceEvent::new(
+                            &self.global(),
+                            atom!("selectend"),
+                            false,
+                            false,
+                            &frame,
+                            &source,
+                        );
+                        event.upcast::<Event>().fire(self.upcast());
+                    }
+                    frame.set_active(false);
+                }
+            },
             _ => (), // XXXManishearth TBD
         }
     }
@@ -244,6 +291,15 @@ impl XRSessionMethods for XRSession {
     /// https://immersive-web.github.io/webxr/#eventdef-xrsession-end
     event_handler!(end, GetOnend, SetOnend);
 
+    /// https://immersive-web.github.io/webxr/#eventdef-xrsession-select
+    event_handler!(select, GetOnselect, SetOnselect);
+
+    /// https://immersive-web.github.io/webxr/#eventdef-xrsession-selectstart
+    event_handler!(selectstart, GetOnselectstart, SetOnselectstart);
+
+    /// https://immersive-web.github.io/webxr/#eventdef-xrsession-selectend
+    event_handler!(selectend, GetOnselectend, SetOnselectend);
+
     /// https://immersive-web.github.io/webxr/#dom-xrsession-mode
     fn Mode(&self) -> XRSessionMode {
         XRSessionMode::Immersive_vr
diff --git a/components/script/dom/xrspace.rs b/components/script/dom/xrspace.rs
index 6fa00d1cffe..ce68e786927 100644
--- a/components/script/dom/xrspace.rs
+++ b/components/script/dom/xrspace.rs
@@ -57,9 +57,9 @@ 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: &Frame) -> ApiPose {
+    pub fn get_pose(&self, base_pose: &Frame) -> Option<ApiPose> {
         if let Some(reference) = self.downcast::<XRReferenceSpace>() {
-            reference.get_pose(base_pose)
+            Some(reference.get_pose(base_pose))
         } else if let Some(source) = self.input_source.get() {
             // XXXManishearth we should be able to request frame information
             // for inputs when necessary instead of always loading it
@@ -72,7 +72,7 @@ impl XRSpace {
                 .iter()
                 .find(|i| i.id == id)
                 .expect("no input found");
-            cast_transform(frame.target_ray_origin)
+            frame.target_ray_origin.map(cast_transform)
         } else {
             unreachable!()
         }