Auto merge of #23485 - Manishearth:xrtest, r=asajeffrey

Basic XR Testing support

This adds support for the XRTest and FakeXRDeviceController APIs from https://github.com/immersive-web/webxr-test-api, and plugs them into the `mock` backend of rust-webvr.

Tested with [a modified webxr test page](https://github.com/immersive-web/webxr-test-api)

r? @jdm @asajeffrey

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8 files changed, 261 insertions, 1 deletions

diff --git a/components/script/dom/fakexrdevicecontroller.rs b/components/script/dom/fakexrdevicecontroller.rs
new file mode 100644
index 00000000000..3d051283155
--- /dev/null
+++ b/components/script/dom/fakexrdevicecontroller.rs
@@ -0,0 +1,104 @@
+/* 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/. */
+
+/* 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::FakeXRDeviceControllerBinding::{
+    self, FakeXRDeviceControllerMethods, FakeXRRigidTransform, FakeXRViewInit,
+};
+use crate::dom::bindings::codegen::Bindings::XRViewBinding::XREye;
+use crate::dom::bindings::error::{Error, Fallible};
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::globalscope::GlobalScope;
+use dom_struct::dom_struct;
+use webvr_traits::{MockVRControlMsg, WebVREyeParameters, WebVRMsg};
+
+#[dom_struct]
+pub struct FakeXRDeviceController {
+    reflector: Reflector,
+}
+
+impl FakeXRDeviceController {
+    pub fn new_inherited() -> FakeXRDeviceController {
+        FakeXRDeviceController {
+            reflector: Reflector::new(),
+        }
+    }
+
+    pub fn new(global: &GlobalScope) -> DomRoot<FakeXRDeviceController> {
+        reflect_dom_object(
+            Box::new(FakeXRDeviceController::new_inherited()),
+            global,
+            FakeXRDeviceControllerBinding::Wrap,
+        )
+    }
+
+    pub fn send_msg(&self, msg: MockVRControlMsg) {
+        self.global()
+            .as_window()
+            .webvr_thread()
+            .unwrap()
+            .send(WebVRMsg::MessageMockDisplay(msg))
+            .unwrap();
+    }
+}
+
+impl FakeXRDeviceControllerMethods for FakeXRDeviceController {
+    /// https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
+    fn SetViews(&self, views: Vec<FakeXRViewInit>) -> Fallible<()> {
+        if views.len() != 2 {
+            return Err(Error::NotSupported);
+        }
+
+        let (left, right) = match (views[0].eye, views[1].eye) {
+            (XREye::Left, XREye::Right) => (&views[0], &views[1]),
+            (XREye::Right, XREye::Left) => (&views[1], &views[0]),
+            _ => return Err(Error::NotSupported),
+        };
+
+        if left.projectionMatrix.len() != 16 ||
+            right.projectionMatrix.len() != 16 ||
+            left.viewOffset.position.len() != 4 ||
+            right.viewOffset.position.len() != 4
+        {
+            return Err(Error::Type("Incorrectly sized array".into()));
+        }
+
+        let mut proj_l = [0.; 16];
+        let mut proj_r = [0.; 16];
+        let v: Vec<_> = left.projectionMatrix.iter().map(|x| **x).collect();
+        proj_l.copy_from_slice(&v);
+        let v: Vec<_> = right.projectionMatrix.iter().map(|x| **x).collect();
+        proj_r.copy_from_slice(&v);
+
+        let mut params_l = WebVREyeParameters::default();
+        let mut params_r = WebVREyeParameters::default();
+        let v: Vec<_> = left.viewOffset.position.iter().map(|x| **x).collect();
+        params_l.offset.copy_from_slice(&v);
+        let v: Vec<_> = right.viewOffset.position.iter().map(|x| **x).collect();
+        params_r.offset.copy_from_slice(&v);
+
+        self.send_msg(MockVRControlMsg::SetProjectionMatrices(proj_l, proj_r));
+        self.send_msg(MockVRControlMsg::SetEyeParameters(params_l, params_r));
+        Ok(())
+    }
+
+    /// https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
+    fn SetViewerOrigin(&self, origin: &FakeXRRigidTransform) -> Fallible<()> {
+        if origin.position.len() != 4 || origin.orientation.len() != 4 {
+            return Err(Error::Type("Incorrectly sized array".into()));
+        }
+        let mut position = [0.; 3];
+        let mut orientation = [0.; 4];
+        let v: Vec<_> = origin.position.iter().map(|x| **x).collect();
+        position.copy_from_slice(&v[0..3]);
+        let v: Vec<_> = origin.orientation.iter().map(|x| **x).collect();
+        orientation.copy_from_slice(&v);
+        self.send_msg(MockVRControlMsg::SetViewerPose(position, orientation));
+        Ok(())
+    }
+}
diff --git a/components/script/dom/mod.rs b/components/script/dom/mod.rs
index 1dbc1383101..cf8d8a49389 100644
--- a/components/script/dom/mod.rs
+++ b/components/script/dom/mod.rs
@@ -301,6 +301,7 @@ pub mod eventsource;
 pub mod eventtarget;
 pub mod extendableevent;
 pub mod extendablemessageevent;
+pub mod fakexrdevicecontroller;
 pub mod file;
 pub mod filelist;
 pub mod filereader;
@@ -551,6 +552,7 @@ pub mod xrrigidtransform;
 pub mod xrsession;
 pub mod xrspace;
 pub mod xrstationaryreferencespace;
+pub mod xrtest;
 pub mod xrview;
 pub mod xrviewerpose;
 pub mod xrviewport;
diff --git a/components/script/dom/webidls/FakeXRDeviceController.webidl b/components/script/dom/webidls/FakeXRDeviceController.webidl
new file mode 100644
index 00000000000..cacdb2f9819
--- /dev/null
+++ b/components/script/dom/webidls/FakeXRDeviceController.webidl
@@ -0,0 +1,49 @@
+/* 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://github.com/immersive-web/webxr-test-api/
+
+[Exposed=Window, Pref="dom.webxr.test"]
+interface FakeXRDeviceController {
+  // Creates and attaches a XRFrameOfReference of the type specified to the device.
+  // void setFrameOfReference(XRFrameOfReferenceType,  FakeXRFrameOfReferenceInit);
+
+  // // Sets the values to be used for subsequent
+  // // requestAnimationFrame() callbacks.
+  [Throws] void setViews(sequence<FakeXRViewInit> views);
+
+  [Throws] void setViewerOrigin(FakeXRRigidTransform origin);
+
+  // Simulates the user activating the reset pose on a device.
+  // void simulateResetPose();
+
+  // Simulates the platform ending the sessions.
+  // void simulateForcedEndSessions();
+
+  // Simulates devices focusing and blurring sessions.
+  // void simulateBlurSession(XRSession);
+  // void simulateFocusSession(XRSession);
+
+  // void setBoundsGeometry(Array<FakeXRBoundsPoint> boundsCoodinates)l
+
+  // Promise<FakeXRInputSourceController>
+  //     simulateInputSourceConnection(FakeXRInputSourceInit);
+};
+
+dictionary FakeXRViewInit {
+  required XREye eye;
+  // https://immersive-web.github.io/webxr/#view-projection-matrix
+  required sequence<float> projectionMatrix;
+  // https://immersive-web.github.io/webxr/#view-offset
+  required FakeXRRigidTransform viewOffset;
+};
+
+dictionary FakeXRBoundsPoint {
+  double x; double z;
+};
+
+dictionary FakeXRRigidTransform {
+    required sequence<float> position;
+    required sequence<float> orientation;
+};
diff --git a/components/script/dom/webidls/XR.webidl b/components/script/dom/webidls/XR.webidl
index 4a6bca26a69..58732edd42b 100644
--- a/components/script/dom/webidls/XR.webidl
+++ b/components/script/dom/webidls/XR.webidl
@@ -28,3 +28,8 @@ dictionary XRSessionCreationOptions {
   XRSessionMode mode = "inline";
   // XRPresentationContext outputContext;
 };
+
+partial interface XR {
+  // https://github.com/immersive-web/webxr-test-api/
+  [SameObject, Pref="dom.webxr.test"] readonly attribute XRTest test;
+};
diff --git a/components/script/dom/webidls/XRTest.webidl b/components/script/dom/webidls/XRTest.webidl
new file mode 100644
index 00000000000..30c485321d4
--- /dev/null
+++ b/components/script/dom/webidls/XRTest.webidl
@@ -0,0 +1,25 @@
+/* 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://github.com/immersive-web/webxr-test-api/
+
+[Exposed=Window, Pref="dom.webxr.test"]
+interface XRTest {
+  // Simulates connecting a device to the system.
+  // Used to instantiate a fake device for use in tests.
+  Promise<FakeXRDeviceController> simulateDeviceConnection(FakeXRDeviceInit init);
+
+  // // Simulates a device being disconnected from the system.
+  // Promise<void> simulateDeviceDisconnection(XRDevice);
+
+  // // Simulates a user activation (aka user gesture) for the current scope.
+  // // The activation is only guaranteed to be valid in the provided function and only applies to WebXR
+  // // Device API methods.
+  // void simulateUserActivation(Function);
+};
+
+dictionary FakeXRDeviceInit {
+    // TODO: Subject to change to match spec changes.
+    required boolean supportsImmersive;
+};
diff --git a/components/script/dom/xr.rs b/components/script/dom/xr.rs
index 3ff67b0042c..1626ad4e00e 100644
--- a/components/script/dom/xr.rs
+++ b/components/script/dom/xr.rs
@@ -21,6 +21,7 @@ use crate::dom::promise::Promise;
 use crate::dom::vrdisplay::VRDisplay;
 use crate::dom::vrdisplayevent::VRDisplayEvent;
 use crate::dom::xrsession::XRSession;
+use crate::dom::xrtest::XRTest;
 use dom_struct::dom_struct;
 use ipc_channel::ipc::IpcSender;
 use profile_traits::ipc;
@@ -36,6 +37,7 @@ pub struct XR {
     gamepads: DomRefCell<Vec<Dom<Gamepad>>>,
     pending_immersive_session: Cell<bool>,
     active_immersive_session: MutNullableDom<VRDisplay>,
+    test: MutNullableDom<XRTest>,
 }
 
 impl XR {
@@ -46,6 +48,7 @@ impl XR {
             gamepads: DomRefCell::new(Vec::new()),
             pending_immersive_session: Cell::new(false),
             active_immersive_session: Default::default(),
+            test: Default::default(),
         }
     }
 
@@ -141,6 +144,11 @@ impl XRMethods for XR {
         session.xr_present(promise.clone());
         promise
     }
+
+    // https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
+    fn Test(&self) -> DomRoot<XRTest> {
+        self.test.or_init(|| XRTest::new(&self.global()))
+    }
 }
 
 impl XR {
diff --git a/components/script/dom/xrspace.rs b/components/script/dom/xrspace.rs
index 30f9246c354..171c0621dc8 100644
--- a/components/script/dom/xrspace.rs
+++ b/components/script/dom/xrspace.rs
@@ -99,7 +99,8 @@ impl XRSpace {
             orient[1] as f64,
             orient[2] as f64,
             orient[3] as f64,
-        );
+        )
+        .normalize();
         RigidTransform3D::new(rotation, translation)
     }
 
diff --git a/components/script/dom/xrtest.rs b/components/script/dom/xrtest.rs
new file mode 100644
index 00000000000..07fac9d6a89
--- /dev/null
+++ b/components/script/dom/xrtest.rs
@@ -0,0 +1,66 @@
+/* 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/. */
+
+/* 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::XRTestBinding::{
+    self, FakeXRDeviceInit, XRTestMethods,
+};
+use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::fakexrdevicecontroller::FakeXRDeviceController;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::promise::Promise;
+use dom_struct::dom_struct;
+use std::cell::Cell;
+use std::rc::Rc;
+use webvr_traits::WebVRMsg;
+
+#[dom_struct]
+pub struct XRTest {
+    reflector: Reflector,
+    session_started: Cell<bool>,
+}
+
+impl XRTest {
+    pub fn new_inherited() -> XRTest {
+        XRTest {
+            reflector: Reflector::new(),
+            session_started: Cell::new(false),
+        }
+    }
+
+    pub fn new(global: &GlobalScope) -> DomRoot<XRTest> {
+        reflect_dom_object(
+            Box::new(XRTest::new_inherited()),
+            global,
+            XRTestBinding::Wrap,
+        )
+    }
+}
+
+impl XRTestMethods for XRTest {
+    /// https://github.com/immersive-web/webxr-test-api/blob/master/explainer.md
+    fn SimulateDeviceConnection(&self, init: &FakeXRDeviceInit) -> Rc<Promise> {
+        let p = Promise::new(&self.global());
+
+        if !init.supportsImmersive || self.session_started.get() {
+            p.reject_native(&());
+            return p;
+        }
+
+        self.session_started.set(true);
+        self.global()
+            .as_window()
+            .webvr_thread()
+            .unwrap()
+            .send(WebVRMsg::CreateMockDisplay)
+            .unwrap();
+        p.resolve_native(&FakeXRDeviceController::new(&self.global()));
+
+        p
+    }
+}