Track displayed surface visibility for idle inhibition

compositor/src/backends/direct.rs

@@ -289,6 +289,9 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
                     });
                 }
 
+                state.display_presentation.clear();
+                state.refresh_idle_inhibition();
+
                 libinput_context.suspend();
                 tracing::info!("direct session paused");
             }
@@ -594,6 +597,18 @@ fn open_primary_device(
                         }
                     }
 
+                    if retired {
+                        if let Some(output) = state
+                            .direct_backend
+                            .as_ref()
+                            .and_then(|backend| backend.devices.get(&node))
+                            .and_then(|device| device.outputs.get(&crtc))
+                        {
+                            state.display_presentation.presented(&output.output);
+                        }
+                        state.refresh_idle_inhibition();
+                    }
+
                     state.record_drm_presentation(node, crtc, metadata.time, metadata.sequence);
                     tracing::trace!(?node, ?crtc, sequence = metadata.sequence, "page flip");
                     let active = state.direct_backend.as_ref().is_some_and(|backend| backend.active);
@@ -661,6 +676,7 @@ pub(crate) fn sleep_locked_outputs(state: &mut Ferese) {
                 Ok(()) => {
                     cancel_output_timers(&state.loop_handle, output);
                     output.power_off = true;
+                    state.display_presentation.remove_output(&output.output);
                 }
 
                 Err(error) => {
@@ -669,6 +685,7 @@ pub(crate) fn sleep_locked_outputs(state: &mut Ferese) {
             }
         }
     }
+    state.refresh_idle_inhibition();
 }
 
 pub(crate) fn wake_locked_outputs(state: &mut Ferese) {
@@ -983,8 +1000,10 @@ fn render_output(
                 &result.states,
                 Kind::Vsync | Kind::HwClock | Kind::HwCompletion,
             );
+            let visibility = result.states.clone();
             drop(result);
             output.surface.queue_frame(presentation)?;
+            state.display_presentation.queued(&output.output, &visibility);
             output.primary_commit = primary_commit;
             output
                 .render_metrics

compositor/src/display_presentation.rs

@@ -0,0 +1,142 @@
+//! Visibility of client content on displayed outputs, independent of capture.
+use std::collections::{HashMap, HashSet};
+
+use smithay::backend::renderer::element::{Id, RenderElementPresentationState, RenderElementStates};
+use smithay::output::Output;
+
+#[derive(Default)]
+struct OutputPresentation {
+    displayed: HashSet<Id>,
+    queued: Option<HashSet<Id>>,
+}
+
+#[derive(Default)]
+pub(crate) struct DisplayPresentation {
+    outputs: HashMap<Output, OutputPresentation>,
+}
+
+fn visible(states: &RenderElementStates) -> HashSet<Id> {
+    states
+        .states
+        .iter()
+        .filter_map(|(id, state)| {
+            (state.visible_area > 0 && state.presentation_state != RenderElementPresentationState::Skipped)
+                .then(|| id.clone())
+        })
+        .collect()
+}
+
+impl DisplayPresentation {
+    // Call only after a successful submission, never from an offscreen capture.
+    pub fn queued(&mut self, output: &Output, states: &RenderElementStates) {
+        self.outputs.entry(output.clone()).or_default().queued = Some(visible(states));
+    }
+
+    pub fn presented(&mut self, output: &Output) {
+        if let Some(record) = self.outputs.get_mut(output)
+            && let Some(queued) = record.queued.take()
+        {
+            record.displayed = queued;
+        }
+    }
+
+    pub fn visible(&self, surface: &Id) -> bool {
+        self.outputs.values().any(|record| record.displayed.contains(surface))
+    }
+
+    pub fn remove_surface(&mut self, surface: &Id) {
+        for record in self.outputs.values_mut() {
+            record.displayed.remove(surface);
+            if let Some(queued) = &mut record.queued {
+                queued.remove(surface);
+            }
+        }
+    }
+
+    pub fn remove_output(&mut self, output: &Output) {
+        self.outputs.remove(output);
+    }
+
+    pub fn clear(&mut self) {
+        self.outputs.clear();
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use smithay::backend::renderer::element::RenderElementState;
+    use smithay::output::{PhysicalProperties, Subpixel};
+
+    use super::*;
+
+    fn output(name: &str) -> Output {
+        Output::new(
+            name.into(),
+            PhysicalProperties {
+                size: (0, 0).into(),
+                subpixel: Subpixel::Unknown,
+                make: "test".into(),
+                model: "test".into(),
+            },
+        )
+    }
+
+    fn scene(id: &Id) -> RenderElementStates {
+        let mut states = RenderElementStates::default();
+        states.states.insert(
+            id.clone(),
+            RenderElementState {
+                visible_area: 20,
+                presentation_state: RenderElementPresentationState::ZeroCopy,
+            },
+        );
+        states
+    }
+
+    #[test]
+    fn visibility_changes_only_when_a_submission_is_presented() {
+        let mut record = DisplayPresentation::default();
+        let output = output("a");
+        let id = Id::new();
+        record.queued(&output, &scene(&id));
+        assert!(!record.visible(&id));
+        record.presented(&output);
+        assert!(record.visible(&id));
+
+        record.queued(&output, &RenderElementStates::default());
+        assert!(record.visible(&id));
+        record.presented(&output);
+        assert!(!record.visible(&id));
+    }
+
+    #[test]
+    fn outputs_are_independent_and_removal_cannot_resurrect_a_surface() {
+        let mut record = DisplayPresentation::default();
+        let a = output("a");
+        let b = output("b");
+        let id = Id::new();
+        for output in [&a, &b] {
+            record.queued(output, &scene(&id));
+            record.presented(output);
+        }
+        record.remove_output(&a);
+        assert!(record.visible(&id));
+        record.queued(&b, &scene(&id));
+        record.remove_surface(&id);
+        record.presented(&b);
+        assert!(!record.visible(&id));
+        record.clear();
+        assert!(!record.visible(&id));
+    }
+
+    #[test]
+    fn occluded_and_skipped_content_do_not_count_as_visible() {
+        let id = Id::new();
+        let mut states = scene(&id);
+        states.states.get_mut(&id).unwrap().visible_area = 0;
+        assert!(visible(&states).is_empty());
+        states.states.get_mut(&id).unwrap().visible_area = 20;
+        states.states.get_mut(&id).unwrap().presentation_state = RenderElementPresentationState::Skipped;
+        assert!(visible(&states).is_empty());
+    }
+}

compositor/src/handlers/compositor.rs

@@ -71,12 +71,31 @@ impl CompositorHandler for Ferese {
                 self.record_client_commit(&window);
             }
         }
+        if !is_sync_subsurface(surface) {
+            let mut surfaces = Vec::new();
+            smithay::desktop::utils::with_surfaces_surface_tree(surface, |surface, _| surfaces.push(surface.clone()));
+            for surface in surfaces {
+                let mapped = smithay::backend::renderer::utils::with_renderer_surface_state(&surface, |state| {
+                    state.buffer().is_some()
+                })
+                .unwrap_or(false);
+                if !mapped {
+                    smithay::desktop::utils::with_surfaces_surface_tree(&surface, |child, _| {
+                        self.display_presentation.remove_surface(&child.into());
+                    });
+                }
+            }
+            self.refresh_idle_inhibition();
+        }
+
         layer_shell::handle_commit(self, surface);
         xdg_shell::handle_commit(&mut self.popups, &mut self.space, surface);
         crate::backends::direct::render_surface(self, surface);
     }
 
     fn destroyed(&mut self, surface: &WlSurface) {
+        self.display_presentation.remove_surface(&surface.into());
+
         if self.session_lock.active {
             self.session_lock
                 .surfaces

compositor/src/handlers/mod.rs

@@ -96,7 +96,7 @@ impl IdleInhibitHandler for Ferese {
     fn inhibit(&mut self, surface: WlSurface) {
         let count = self.idle_inhibitors.entry(surface).or_default();
         *count = count.saturating_add(1);
-        self.idle_notifier_state.set_is_inhibited(true);
+        self.refresh_idle_inhibition();
     }
 
     fn uninhibit(&mut self, surface: WlSurface) {

compositor/src/main.rs

@@ -5,6 +5,7 @@ mod config;
 mod cursor;
 mod daemon;
 mod dimming;
+mod display_presentation;
 mod effects;
 mod floating;
 mod frame_scheduler;

compositor/src/portal_session.rs

@@ -235,8 +235,12 @@ impl PortalSession {
 
 impl crate::Ferese {
     pub(crate) fn refresh_idle_inhibition(&mut self) {
-        self.idle_notifier_state
-            .set_is_inhibited(!self.idle_inhibitors.is_empty() || self.portal_session.idle_inhibited());
+        self.idle_notifier_state.set_is_inhibited(
+            self.idle_inhibitors
+                .keys()
+                .any(|surface| self.display_presentation.visible(&surface.into()))
+                || self.portal_session.idle_inhibited(),
+        );
     }
 
     pub(crate) fn end_portal_session(&mut self) {

compositor/src/session_lock.rs

@@ -236,6 +236,8 @@ impl SessionLockHandler for Ferese {
         }
         self.cancel_logout_confirmation();
         self.session_lock.active = true;
+        self.display_presentation.clear();
+        self.refresh_idle_inhibition();
         self.session_lock.idle_since = Some(Instant::now());
         match self
             .loop_handle
@@ -302,6 +304,8 @@ impl SessionLockHandler for Ferese {
         }
         let sleeping = self.session_lock.sleeping;
         self.session_lock = Lock::default();
+        self.display_presentation.clear();
+        self.refresh_idle_inhibition();
         if sleeping {
             crate::backends::direct::wake_locked_outputs(self);
         }

compositor/src/state.rs

@@ -334,6 +334,7 @@ pub struct Ferese {
     output_identity_ids: HashMap<String, OutputId>,
     pub(crate) windows: WindowRegistry<Window>,
     pub(crate) render: crate::render::RenderResources,
+    pub(crate) display_presentation: crate::display_presentation::DisplayPresentation,
     pub(crate) nested_backend: Option<NestedBackend>,
     pub(crate) wallpaper: WallpaperState,
     window_stack: WindowStack,
@@ -561,6 +562,7 @@ impl Ferese {
             output_identity_ids: HashMap::new(),
             windows: WindowRegistry::default(),
             render: Default::default(),
+            display_presentation: Default::default(),
             nested_backend: None,
             wallpaper: WallpaperState::with_wakeup(config.wallpaper, Some(event_loop.get_signal())),
             window_stack: WindowStack::default(),

compositor/src/state/layout.rs

@@ -44,8 +44,13 @@ impl Ferese {
                 geometry.settle_presentation();
             }
 
+            window.with_surfaces(|surface, _| {
+                self.display_presentation.remove_surface(&surface.into());
+            });
             self.space.unmap_elem(&window);
         }
+        self.refresh_idle_inhibition();
+
         changed
     }
 

compositor/src/state/outputs.rs

@@ -53,6 +53,9 @@ impl Ferese {
     }
 
     pub fn unregister_output(&mut self, output: &Output) {
+        self.display_presentation.remove_output(output);
+        self.refresh_idle_inhibition();
+
         let Some(output_id) = self.output_ids.remove(output) else {
             return;
         };

compositor/src/winit.rs

@@ -183,6 +183,10 @@ pub fn init(event_loop: &mut EventLoop<Ferese>, state: &mut Ferese) -> Result<()
                         state.loop_signal.stop();
                         return;
                     }
+                    state.display_presentation.queued(&output, &rendered_states);
+                    state.display_presentation.presented(&output);
+                    state.refresh_idle_inhibition();
+
                     if state.session_lock.active {
                         state.lock_frame_presented(&output);
                     }