Add Views::Inline

webxr-api/device.rs

@@ -42,12 +42,13 @@ pub trait DeviceAPI<Surface>: 'static {
 
     /// A resolution large enough to contain all the viewports.
     /// https://immersive-web.github.io/webxr/#native-webgl-framebuffer-resolution
-    fn recommended_framebuffer_resolution(&self) -> Size2D<i32, Viewport> {
+    fn recommended_framebuffer_resolution(&self) -> Option<Size2D<i32, Viewport>> {
         let viewport = match self.views() {
+            Views::Inline => return None,
             Views::Mono(view) => view.viewport,
             Views::Stereo(left, right) => left.viewport.union(&right.viewport),
         };
-        Size2D::new(viewport.max_x(), viewport.max_y())
+        Some(Size2D::new(viewport.max_x(), viewport.max_y()))
     }
 
     /// This method should block waiting for the next frame,

webxr-api/session.rs

@@ -84,7 +84,7 @@ impl Quitter {
 pub struct Session {
     floor_transform: RigidTransform3D<f32, Native, Floor>,
     views: Views,
-    resolution: Size2D<i32, Viewport>,
+    resolution: Option<Size2D<i32, Viewport>>,
     sender: Sender<SessionMsg>,
     environment_blend_mode: EnvironmentBlendMode,
     initial_inputs: Vec<InputSource>,
@@ -109,6 +109,7 @@ impl Session {
 
     pub fn recommended_framebuffer_resolution(&self) -> Size2D<i32, Viewport> {
         self.resolution
+            .expect("Inline XR sessions should not construct a framebuffer")
     }
 
     pub fn set_swap_chain(&mut self, swap_chain_id: Option<SwapChainId>) {

webxr-api/view.rs

@@ -87,6 +87,8 @@ impl<Eye> Default for View<Eye> {
 #[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>),
 }

webxr/headless/mod.rs

@@ -51,6 +51,7 @@ struct InputInfo {
 
 struct HeadlessDevice {
     data: Arc<Mutex<HeadlessDeviceData>>,
+    mode: SessionMode,
 }
 
 struct HeadlessDeviceData {
@@ -110,7 +111,7 @@ impl DiscoveryAPI<SwapChains> for HeadlessDiscovery {
             return Err(Error::NoMatchingDevice);
         }
         let data = self.data.clone();
-        xr.run_on_main_thread(move || Ok(HeadlessDevice { data }))
+        xr.run_on_main_thread(move || Ok(HeadlessDevice { data, mode }))
     }
 
     fn supports_session(&self, mode: SessionMode) -> bool {
@@ -124,7 +125,11 @@ impl DeviceAPI<Surface> for HeadlessDevice {
     }
 
     fn views(&self) -> Views {
-        self.data.lock().unwrap().views.clone()
+        if self.mode == SessionMode::Inline {
+            Views::Inline
+        } else {
+            self.data.lock().unwrap().views.clone()
+        }
     }
 
     fn wait_for_animation_frame(&mut self) -> Option<Frame> {