On Wayland, Hide CSD for fullscreen windows (#1473)

CHANGELOG.md

@@ -7,6 +7,7 @@
 - On Wayland, Add HiDPI cursor support
 - On Web, add the ability to query "Light" or "Dark" system theme send `ThemeChanged` on change.
 - Fix `Event::to_static` returning `None` for user events.
+- On Wayland, Hide CSD for fullscreen windows.
 
 # 0.21.0 (2020-02-04)
 

src/platform_impl/linux/wayland/event_loop.rs

@@ -39,7 +39,10 @@ use crate::{
     window::{CursorIcon, WindowId as RootWindowId},
 };
 
-use super::{window::WindowStore, DeviceId, WindowId};
+use super::{
+    window::{DecorationsAction, WindowStore},
+    DeviceId, WindowId,
+};
 
 use smithay_client_toolkit::{
     output::OutputMgr,
@@ -713,6 +716,13 @@ impl<T> EventLoop<T> {
                 crate::window::WindowId(crate::platform_impl::WindowId::Wayland(window.wid));
             if let Some(frame) = window.frame {
                 if let Some((w, h)) = window.newsize {
+                    // Update decorations state
+                    match window.decorations_action {
+                        Some(DecorationsAction::Hide) => frame.set_decorate(false),
+                        Some(DecorationsAction::Show) => frame.set_decorate(true),
+                        None => (),
+                    }
+
                     // mutter (GNOME Wayland) relies on `set_geometry` to reposition window in case
                     // it overlaps mutter's `bounding box`, so we can't avoid this resize call,
                     // which calls `set_geometry` under the hood, for now.

src/platform_impl/linux/wayland/window.rs

@@ -41,6 +41,13 @@ pub struct Window {
     need_refresh: Arc<Mutex<bool>>,
     fullscreen: Arc<Mutex<bool>>,
     cursor_grab_changed: Arc<Mutex<Option<bool>>>, // Update grab state
+    decorated: Arc<Mutex<bool>>,
+}
+
+#[derive(Clone, Copy, Debug)]
+pub enum DecorationsAction {
+    Hide,
+    Show,
 }
 
 impl Window {
@@ -69,6 +76,9 @@ impl Window {
 
         let window_store = evlp.store.clone();
 
+        let decorated = Arc::new(Mutex::new(attributes.decorations));
+        let pending_decorations_action = Arc::new(Mutex::new(None));
+
         let my_surface = surface.clone();
         let mut frame = SWindow::<ConceptFrame>::init_from_env(
             &evlp.env,
@@ -83,7 +93,23 @@ impl Window {
                         if window.surface.as_ref().equals(&my_surface.as_ref()) {
                             window.newsize = new_size;
                             *(window.need_refresh.lock().unwrap()) = true;
-                            *(window.fullscreen.lock().unwrap()) = is_fullscreen;
+                            {
+                                // Get whether we're in fullscreen
+                                let mut fullscreen = window.fullscreen.lock().unwrap();
+                                // Fullscreen state was changed, so update decorations
+                                if *fullscreen != is_fullscreen {
+                                    let decorated = { *window.decorated.lock().unwrap() };
+                                    if decorated {
+                                        *window.pending_decorations_action.lock().unwrap() =
+                                            if is_fullscreen {
+                                                Some(DecorationsAction::Hide)
+                                            } else {
+                                                Some(DecorationsAction::Show)
+                                            };
+                                    }
+                                }
+                                *fullscreen = is_fullscreen;
+                            }
                             *(window.need_frame_refresh.lock().unwrap()) = true;
                             return;
                         }
@@ -174,6 +200,8 @@ impl Window {
             frame: Arc::downgrade(&frame),
             current_dpi: 1,
             new_dpi: None,
+            decorated: decorated.clone(),
+            pending_decorations_action: pending_decorations_action.clone(),
         });
         evlp.evq.borrow_mut().sync_roundtrip().unwrap();
 
@@ -189,6 +217,7 @@ impl Window {
             cursor_manager,
             fullscreen,
             cursor_grab_changed,
+            decorated,
         })
     }
 
@@ -277,6 +306,7 @@ impl Window {
     }
 
     pub fn set_decorations(&self, decorate: bool) {
+        *(self.decorated.lock().unwrap()) = decorate;
         self.frame.lock().unwrap().set_decorate(decorate);
         *(self.need_frame_refresh.lock().unwrap()) = true;
     }
@@ -409,6 +439,8 @@ struct InternalWindow {
     frame: Weak<Mutex<SWindow<ConceptFrame>>>,
     current_dpi: i32,
     new_dpi: Option<i32>,
+    decorated: Arc<Mutex<bool>>,
+    pending_decorations_action: Arc<Mutex<Option<DecorationsAction>>>,
 }
 
 pub struct WindowStore {
@@ -425,6 +457,7 @@ pub struct WindowStoreForEach<'a> {
     pub surface: &'a wl_surface::WlSurface,
     pub wid: WindowId,
     pub frame: Option<&'a mut SWindow<ConceptFrame>>,
+    pub decorations_action: Option<DecorationsAction>,
 }
 
 impl WindowStore {
@@ -482,6 +515,7 @@ impl WindowStore {
             let opt_arc = window.frame.upgrade();
             let mut opt_mutex_lock = opt_arc.as_ref().map(|m| m.lock().unwrap());
             let mut size = { *window.size.lock().unwrap() };
+            let decorations_action = { window.pending_decorations_action.lock().unwrap().take() };
             f(WindowStoreForEach {
                 newsize: window.newsize.take(),
                 size: &mut size,
@@ -492,6 +526,7 @@ impl WindowStore {
                 surface: &window.surface,
                 wid: make_wid(&window.surface),
                 frame: opt_mutex_lock.as_mut().map(|m| &mut **m),
+                decorations_action,
             });
             *window.size.lock().unwrap() = size;
             if let Some(dpi) = window.new_dpi.take() {