On Wayland, improve initial user size handling

Keep the user provided size in the original values and convert only
when we're getting a `configure` event. On some compositors will
have a scale available, so it'll work, however with some we'll
still have old 'pick 1` as default.

Also configure_bounds when compositor tells the user to pick the size,
that will ensure that initial `with_inner_size` won't grow beyond the
working area.

Fixes rust-windowing#3187.

CHANGELOG.md

@@ -11,7 +11,10 @@ Unreleased` header.
 
 # Unreleased
 
+- On Wayland, apply correct scale to `PhysicalSize` passed in `WindowBuilder::with_inner_size` when possible.
 - On Wayland, fix `RedrawRequsted` being always sent without decorations and `sctk-adwaita` feature.
+- On Wayland, ignore resize requests when the window is fully tiled.
+- On Wayland, use `configure_bounds` to constrain `with_inner_size` when compositor wants users to pick size.
 - On Windows, fix deadlock when accessing the state during `Cursor{Enter,Leave}`.
 - On macOS, fix deadlock when entering a nested event loop from an event handler.
 

src/platform_impl/linux/wayland/event_loop/mod.rs

@@ -393,7 +393,7 @@ impl<T: 'static> EventLoop<T> {
                     self.with_state(|state| {
                         let windows = state.windows.get_mut();
                         let mut window = windows.get(&window_id).unwrap().lock().unwrap();
-                        window.resize(new_logical_size);
+                        window.request_inner_size(new_logical_size.into());
                     });
                 }
 

src/platform_impl/linux/wayland/window/mod.rs

@@ -97,11 +97,9 @@ impl Window {
             .map(|activation_state| activation_state.global().clone());
         let display = event_loop_window_target.connection.display();
 
-        // XXX The initial scale factor must be 1, but it might cause sizing issues on HiDPI.
-        let size: LogicalSize<u32> = attributes
+        let size: Size = attributes
             .inner_size
-            .map(|size| size.to_logical::<u32>(1.))
-            .unwrap_or((800, 600).into());
+            .unwrap_or(LogicalSize::new(800., 600.).into());
 
         // We prefer server side decorations, however to not have decorations we ask for client
         // side decorations instead.
@@ -141,7 +139,8 @@ impl Window {
         // Set the window title.
         window_state.set_title(attributes.title);
 
-        // Set the min and max sizes.
+        // Set the min and max sizes. We must set the hints upon creating a window, so
+        // we use the default `1.` scaling...
         let min_size = attributes.min_inner_size.map(|size| size.to_logical(1.));
         let max_size = attributes.max_inner_size.map(|size| size.to_logical(1.));
         window_state.set_min_inner_size(min_size);
@@ -315,12 +314,9 @@ impl Window {
     #[inline]
     pub fn request_inner_size(&self, size: Size) -> Option<PhysicalSize<u32>> {
         let mut window_state = self.window_state.lock().unwrap();
-        let scale_factor = window_state.scale_factor();
-        window_state.resize(size.to_logical::<u32>(scale_factor));
-
+        let new_size = window_state.request_inner_size(size);
         self.request_redraw();
-
-        Some(window_state.inner_size().to_physical(scale_factor))
+        Some(new_size)
     }
 
     /// Set the minimum inner size for the window.

src/platform_impl/linux/wayland/window/state.rs

@@ -28,7 +28,7 @@ use sctk::shm::Shm;
 use sctk::subcompositor::SubcompositorState;
 use wayland_protocols_plasma::blur::client::org_kde_kwin_blur::OrgKdeKwinBlur;
 
-use crate::dpi::{LogicalPosition, LogicalSize};
+use crate::dpi::{LogicalPosition, LogicalSize, PhysicalSize, Size};
 use crate::error::{ExternalError, NotSupportedError};
 use crate::event::WindowEvent;
 use crate::platform_impl::wayland::event_loop::sink::EventSink;
@@ -133,6 +133,10 @@ pub struct WindowState {
     /// sends `None` for the new size in the configure.
     stateless_size: LogicalSize<u32>,
 
+    /// Initial window size provided by the user. Removed on the first
+    /// configure.
+    initial_size: Option<Size>,
+
     /// The state of the frame callback.
     frame_callback_state: FrameCallbackState,
 
@@ -153,7 +157,7 @@ impl WindowState {
         connection: Connection,
         queue_handle: &QueueHandle<WinitState>,
         winit_state: &WinitState,
-        size: LogicalSize<u32>,
+        initial_size: Size,
         window: Window,
         theme: Option<Theme>,
     ) -> Self {
@@ -194,8 +198,9 @@ impl WindowState {
             resizable: true,
             scale_factor: 1.,
             shm: winit_state.shm.wl_shm().clone(),
-            size,
-            stateless_size: size,
+            size: initial_size.to_logical(1.),
+            stateless_size: initial_size.to_logical(1.),
+            initial_size: Some(initial_size),
             text_inputs: Vec::new(),
             theme,
             title: String::default(),
@@ -253,6 +258,14 @@ impl WindowState {
         subcompositor: &Arc<SubcompositorState>,
         event_sink: &mut EventSink,
     ) -> LogicalSize<u32> {
+        // NOTE: when using fractional scaling or wl_compositor@v6 the scaling
+        // should be delivered before the first configure, thus apply it to
+        // properly scale the physical sizes provided by the users.
+        if let Some(initial_size) = self.initial_size.take() {
+            self.size = initial_size.to_logical(self.scale_factor());
+            self.stateless_size = self.size;
+        }
+
         if configure.decoration_mode == DecorationMode::Client
             && self.frame.is_none()
             && !self.csd_fails
@@ -297,30 +310,46 @@ impl WindowState {
             event_sink.push_window_event(WindowEvent::Occluded(occluded), window_id);
         }
 
-        let new_size = if let Some(frame) = self.frame.as_mut() {
+        let (mut new_size, constrain) = if let Some(frame) = self.frame.as_mut() {
             // Configure the window states.
             frame.update_state(configure.state);
 
             match configure.new_size {
                 (Some(width), Some(height)) => {
                     let (width, height) = frame.subtract_borders(width, height);
                     (
-                        width.map(|w| w.get()).unwrap_or(1),
-                        height.map(|h| h.get()).unwrap_or(1),
+                        (
+                            width.map(|w| w.get()).unwrap_or(1),
+                            height.map(|h| h.get()).unwrap_or(1),
+                        )
+                            .into(),
+                        false,
                     )
-                        .into()
                 }
-                (_, _) if stateless => self.stateless_size,
-                _ => self.size,
+                (_, _) if stateless => (self.stateless_size, true),
+                _ => (self.size, true),
             }
         } else {
             match configure.new_size {
-                (Some(width), Some(height)) => (width.get(), height.get()).into(),
-                _ if stateless => self.stateless_size,
-                _ => self.size,
+                (Some(width), Some(height)) => ((width.get(), height.get()).into(), false),
+                _ if stateless => (self.stateless_size, true),
+                _ => (self.size, true),
             }
         };
 
+        // Apply configure bounds only when compositor let the user decide what size to pick.
+        if constrain {
+            let bounds = self.inner_size_bounds(&configure);
+            new_size.width = bounds
+                .0
+                .map(|bound_w| new_size.width.min(bound_w.get()))
+                .unwrap_or(new_size.width);
+            new_size.height = bounds
+                .1
+                .map(|bound_h| new_size.height.min(bound_h.get()))
+                .unwrap_or(new_size.height);
+        }
+
         // XXX Set the configure before doing a resize.
         self.last_configure = Some(configure);
 
@@ -330,6 +359,30 @@ impl WindowState {
         new_size
     }
 
+    /// Compute the bounds for the inner size of the surface.
+    fn inner_size_bounds(
+        &self,
+        configure: &WindowConfigure,
+    ) -> (Option<NonZeroU32>, Option<NonZeroU32>) {
+        let configure_bounds = match configure.suggested_bounds {
+            Some((width, height)) => (NonZeroU32::new(width), NonZeroU32::new(height)),
+            None => (None, None),
+        };
+
+        if let Some(frame) = self.frame.as_ref() {
+            let (width, height) = frame.subtract_borders(
+                configure_bounds.0.unwrap_or(NonZeroU32::new(1).unwrap()),
+                configure_bounds.1.unwrap_or(NonZeroU32::new(1).unwrap()),
+            );
+            (
+                configure_bounds.0.and(width),
+                configure_bounds.1.and(height),
+            )
+        } else {
+            configure_bounds
+        }
+    }
+
     #[inline]
     fn is_stateless(configure: &WindowConfigure) -> bool {
         !(configure.is_maximized() || configure.is_fullscreen() || configure.is_tiled())
@@ -568,8 +621,22 @@ impl WindowState {
         }
     }
 
+    /// Try to resize the window when the user can do so.
+    pub fn request_inner_size(&mut self, inner_size: Size) -> PhysicalSize<u32> {
+        if self
+            .last_configure
+            .as_ref()
+            .map(Self::is_stateless)
+            .unwrap_or(true)
+        {
+            self.resize(inner_size.to_logical(self.scale_factor()))
+        }
+
+        self.inner_size().to_physical(self.scale_factor())
+    }
+
     /// Resize the window to the new inner size.
-    pub fn resize(&mut self, inner_size: LogicalSize<u32>) {
+    fn resize(&mut self, inner_size: LogicalSize<u32>) {
         self.size = inner_size;
 
         // Update the stateless size.

src/platform_impl/linux/x11/monitor.rs

@@ -212,7 +212,7 @@ impl XConnection {
             return Ok(MonitorHandle::dummy());
         }
 
-        let default = monitors.get(0).unwrap();
+        let default = monitors.first().unwrap();
 
         let window_rect = match window_rect {
             Some(rect) => rect,