Merge webxr repository (#35228)

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

components/shared/webxr/view.rs

@@ -0,0 +1,170 @@
+/* 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 crate uses `euclid`'s typed units, and exposes different coordinate spaces.
+
+use euclid::Rect;
+use euclid::RigidTransform3D;
+use euclid::Transform3D;
+
+#[cfg(feature = "ipc")]
+use serde::{Deserialize, Serialize};
+
+use std::marker::PhantomData;
+
+/// The coordinate space of the viewer
+/// https://immersive-web.github.io/webxr/#dom-xrreferencespacetype-viewer
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Viewer {}
+
+/// The coordinate space of the floor
+/// https://immersive-web.github.io/webxr/#dom-xrreferencespacetype-local-floor
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Floor {}
+
+/// The coordinate space of the left eye
+/// https://immersive-web.github.io/webxr/#dom-xreye-left
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum LeftEye {}
+
+/// The coordinate space of the right eye
+/// https://immersive-web.github.io/webxr/#dom-xreye-right
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum RightEye {}
+
+/// The coordinate space of the left frustrum of a cubemap
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum CubeLeft {}
+
+/// The coordinate space of the right frustrum of a cubemap
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum CubeRight {}
+
+/// The coordinate space of the top frustrum of a cubemap
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum CubeTop {}
+
+/// The coordinate space of the bottom frustrum of a cubemap
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum CubeBottom {}
+
+/// The coordinate space of the back frustrum of a cubemap
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum CubeBack {}
+
+/// Pattern-match on eyes
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub struct SomeEye<Eye>(u8, PhantomData<Eye>);
+pub const LEFT_EYE: SomeEye<LeftEye> = SomeEye(0, PhantomData);
+pub const RIGHT_EYE: SomeEye<RightEye> = SomeEye(1, PhantomData);
+pub const VIEWER: SomeEye<Viewer> = SomeEye(2, PhantomData);
+pub const CUBE_LEFT: SomeEye<CubeLeft> = SomeEye(3, PhantomData);
+pub const CUBE_RIGHT: SomeEye<CubeRight> = SomeEye(4, PhantomData);
+pub const CUBE_TOP: SomeEye<CubeTop> = SomeEye(5, PhantomData);
+pub const CUBE_BOTTOM: SomeEye<CubeBottom> = SomeEye(6, PhantomData);
+pub const CUBE_BACK: SomeEye<CubeBack> = SomeEye(7, PhantomData);
+
+impl<Eye1, Eye2> PartialEq<SomeEye<Eye2>> for SomeEye<Eye1> {
+    fn eq(&self, rhs: &SomeEye<Eye2>) -> bool {
+        self.0 == rhs.0
+    }
+}
+
+/// The native 3D coordinate space of the device
+/// This is not part of the webvr specification.
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Native {}
+
+/// The normalized device coordinate space, where the display
+/// is from (-1,-1) to (1,1).
+// TODO: are we OK assuming that we can use the same coordinate system for all displays?
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Display {}
+
+/// The unnormalized device coordinate space, where the display
+/// is from (0,0) to (w,h), measured in pixels.
+// TODO: are we OK assuming that we can use the same coordinate system for all displays?
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Viewport {}
+
+/// The coordinate space of an input device
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Input {}
+
+/// The coordinate space of a secondary capture view
+#[derive(Clone, Copy, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Capture {}
+
+/// For each eye, the pose of that eye,
+/// its projection onto its display.
+/// For stereo displays, we have a `View<LeftEye>` and a `View<RightEye>`.
+/// For mono displays, we hagve a `View<Viewer>`
+/// https://immersive-web.github.io/webxr/#xrview
+#[derive(Clone, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub struct View<Eye> {
+    pub transform: RigidTransform3D<f32, Eye, Native>,
+    pub projection: Transform3D<f32, Eye, Display>,
+}
+
+impl<Eye> Default for View<Eye> {
+    fn default() -> Self {
+        View {
+            transform: RigidTransform3D::identity(),
+            projection: Transform3D::identity(),
+        }
+    }
+}
+
+impl<Eye> View<Eye> {
+    pub fn cast_unit<NewEye>(&self) -> View<NewEye> {
+        View {
+            transform: self.transform.cast_unit(),
+            projection: Transform3D::from_untyped(&self.projection.to_untyped()),
+        }
+    }
+}
+
+/// Whether a device is mono or stereo, and the views it supports.
+#[derive(Clone, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub enum Views {
+    /// Mono view for inline VR, viewport and projection matrices are calculated by client
+    Inline,
+    Mono(View<Viewer>),
+    Stereo(View<LeftEye>, View<RightEye>),
+    StereoCapture(View<LeftEye>, View<RightEye>, View<Capture>),
+    Cubemap(
+        View<Viewer>,
+        View<CubeLeft>,
+        View<CubeRight>,
+        View<CubeTop>,
+        View<CubeBottom>,
+        View<CubeBack>,
+    ),
+}
+
+/// A list of viewports per-eye in the order of fields in Views.
+///
+/// Not all must be in active use.
+#[derive(Clone, Debug)]
+#[cfg_attr(feature = "ipc", derive(Serialize, Deserialize))]
+pub struct Viewports {
+    pub viewports: Vec<Rect<i32, Viewport>>,
+}