Filter out webidl files based on special comments, and feature-gate webxr interfaces. (#34348)

* Filter out webidl files based on skip-if directives.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* script: Don't build XR functionality without webxr feature.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* Fix tidy.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* script: Adjust imports for file movement.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* Fix clippy.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* Formatting.

Signed-off-by: Josh Matthews <josh@joshmatthews.net>

* Clean up webxr module import.

Co-authored-by: Samson <16504129+sagudev@users.noreply.github.com>
Signed-off-by: Josh Matthews <josh@joshmatthews.net>

---------

Signed-off-by: Josh Matthews <josh@joshmatthews.net>
Co-authored-by: Samson <16504129+sagudev@users.noreply.github.com>

components/script/dom/webxr/xrview.rs

@@ -0,0 +1,137 @@
+/* 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 std::cell::Cell;
+
+use dom_struct::dom_struct;
+use euclid::RigidTransform3D;
+use js::typedarray::{Float32, Float32Array};
+use webxr_api::{ApiSpace, View};
+
+use crate::dom::bindings::buffer_source::HeapBufferSource;
+use crate::dom::bindings::codegen::Bindings::XRViewBinding::{XREye, XRViewMethods};
+use crate::dom::bindings::num::Finite;
+use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::xrrigidtransform::XRRigidTransform;
+use crate::dom::xrsession::{cast_transform, BaseSpace, BaseTransform, XRSession};
+use crate::script_runtime::{CanGc, JSContext};
+
+#[dom_struct]
+pub struct XRView {
+    reflector_: Reflector,
+    session: Dom<XRSession>,
+    eye: XREye,
+    viewport_index: usize,
+    #[ignore_malloc_size_of = "mozjs"]
+    proj: HeapBufferSource<Float32>,
+    #[ignore_malloc_size_of = "defined in rust-webxr"]
+    #[no_trace]
+    view: View<ApiSpace>,
+    transform: Dom<XRRigidTransform>,
+    requested_viewport_scale: Cell<f64>,
+}
+
+impl XRView {
+    fn new_inherited(
+        session: &XRSession,
+        transform: &XRRigidTransform,
+        eye: XREye,
+        viewport_index: usize,
+        view: View<ApiSpace>,
+    ) -> XRView {
+        XRView {
+            reflector_: Reflector::new(),
+            session: Dom::from_ref(session),
+            eye,
+            viewport_index,
+            proj: HeapBufferSource::default(),
+            view,
+            transform: Dom::from_ref(transform),
+            requested_viewport_scale: Cell::new(1.0),
+        }
+    }
+
+    pub fn new<V: Copy>(
+        global: &GlobalScope,
+        session: &XRSession,
+        view: &View<V>,
+        eye: XREye,
+        viewport_index: usize,
+        to_base: &BaseTransform,
+        can_gc: CanGc,
+    ) -> DomRoot<XRView> {
+        let transform: RigidTransform3D<f32, V, BaseSpace> = view.transform.then(to_base);
+        let transform = XRRigidTransform::new(global, cast_transform(transform), can_gc);
+
+        reflect_dom_object(
+            Box::new(XRView::new_inherited(
+                session,
+                &transform,
+                eye,
+                viewport_index,
+                view.cast_unit(),
+            )),
+            global,
+        )
+    }
+
+    pub fn session(&self) -> &XRSession {
+        &self.session
+    }
+
+    pub fn viewport_index(&self) -> usize {
+        self.viewport_index
+    }
+}
+
+impl XRViewMethods<crate::DomTypeHolder> for XRView {
+    /// <https://immersive-web.github.io/webxr/#dom-xrview-eye>
+    fn Eye(&self) -> XREye {
+        self.eye
+    }
+
+    /// <https://immersive-web.github.io/webxr/#dom-xrview-projectionmatrix>
+    fn ProjectionMatrix(&self, _cx: JSContext) -> Float32Array {
+        if !self.proj.is_initialized() {
+            let cx = GlobalScope::get_cx();
+            // row_major since euclid uses row vectors
+            let proj = self.view.projection.to_array();
+            self.proj
+                .set_data(cx, &proj)
+                .expect("Failed to set projection matrix.")
+        }
+        self.proj
+            .get_buffer()
+            .expect("Failed to get projection matrix.")
+    }
+
+    /// <https://immersive-web.github.io/webxr/#dom-xrview-transform>
+    fn Transform(&self) -> DomRoot<XRRigidTransform> {
+        DomRoot::from_ref(&self.transform)
+    }
+
+    /// <https://www.w3.org/TR/webxr/#dom-xrview-recommendedviewportscale>
+    fn GetRecommendedViewportScale(&self) -> Option<Finite<f64>> {
+        // Just return 1.0 since we currently will always use full-sized viewports
+        Finite::new(1.0)
+    }
+
+    /// <https://www.w3.org/TR/webxr/#dom-xrview-requestviewportscale>
+    fn RequestViewportScale(&self, scale: Option<Finite<f64>>) {
+        if let Some(scale) = scale {
+            if *scale > 0.0 {
+                let clamped_scale = scale.clamp(0.0, 1.0);
+                self.requested_viewport_scale.set(clamped_scale);
+            }
+        }
+    }
+
+    /// <https://www.w3.org/TR/webxr-ar-module-1/#dom-xrview-isfirstpersonobserver>
+    fn IsFirstPersonObserver(&self) -> bool {
+        // Servo is not currently supported anywhere that supports this, so return false
+        false
+    }
+}