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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1 files changed, 104 insertions, 0 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(())
+    }
+}