Some better naming and cleanup of viewport.rs

crates/eframe/src/native/run.rs

@@ -1086,7 +1086,7 @@ mod glow_integration {
                 let painter = Rc::downgrade(&painter);
                 let beginning = integration.beginning;
 
-                integration.egui_ctx.set_render_sync_callback(
+                integration.egui_ctx.set_immediate_viewport_renderer(
                     move |egui_ctx, viewport_builder, id_pair, viewport_ui_cb| {
                         if let (Some(glutin), Some(gl), Some(painter)) =
                             (glutin.upgrade(), gl.upgrade(), painter.upgrade())
@@ -2210,7 +2210,7 @@ mod wgpu_integration {
                 let viewport_maps = Rc::downgrade(&viewport_maps);
                 let beginning = integration.beginning;
 
-                integration.egui_ctx.set_render_sync_callback(
+                integration.egui_ctx.set_immediate_viewport_renderer(
                     move |egui_ctx, viewport_builder, id_pair, viewport_ui_cb| {
                         if let (
                             Some(viewports),

crates/egui/src/context.rs

@@ -139,7 +139,7 @@ impl Repaint {
 // ----------------------------------------------------------------------------
 
 thread_local! {
-    static EGUI_RENDER_SYNC: RefCell<Option<Box<ViewportRenderSyncCallback>>> = Default::default();
+    static IMMEDIATE_VIEWPORT_RENDERER: RefCell<Option<Box<ImmediateViewportRendererCallback>>> = Default::default();
 }
 
 // ----------------------------------------------------------------------------
@@ -170,7 +170,7 @@ struct ContextImpl {
 
     repaint: Repaint,
 
-    viewports: ViewportIdMap<Viewport>,
+    viewports: ViewportIdMap<ViewportState>,
     viewport_commands: Vec<(ViewportId, ViewportCommand)>,
 
     embed_viewports: bool,
@@ -2508,15 +2508,15 @@ impl Context {
     ///
     /// When a viewport sync is created will be rendered by this function
     ///
-    /// Look in `crates/eframe/native/run.rs` and search for `set_render_sync_callback` to see for what is used.
+    /// Look in `crates/eframe/native/run.rs` and search for `set_immediate_viewport_renderer` to see for what is used.
     #[allow(clippy::unused_self)]
-    pub fn set_render_sync_callback(
+    pub fn set_immediate_viewport_renderer(
         &self,
         callback: impl for<'a> Fn(&Context, ViewportBuilder, ViewportIdPair, Box<dyn FnOnce(&Context) + 'a>)
             + 'static,
     ) {
         let callback = Box::new(callback);
-        EGUI_RENDER_SYNC.with(|render_sync| {
+        IMMEDIATE_VIEWPORT_RENDERER.with(|render_sync| {
             render_sync.replace(Some(callback));
         });
     }
@@ -2586,7 +2586,7 @@ impl Context {
                 } else {
                     ctx.viewports.insert(
                         viewport_builder.id,
-                        Viewport {
+                        ViewportState {
                             id_pair: ViewportIdPair {
                                 this: viewport_builder.id,
                                 parent: viewport_id,
@@ -2628,9 +2628,9 @@ impl Context {
             return viewport_ui_cb(self);
         }
 
-        EGUI_RENDER_SYNC.with(|render_sync_viewport_cb| {
+        IMMEDIATE_VIEWPORT_RENDERER.with(|immediate_viewport_renderer| {
-            let render_sync_viewport_cb = render_sync_viewport_cb.borrow();
+            let immediate_viewport_renderer = immediate_viewport_renderer.borrow();
-            let Some(render_sync_viewport_cb) = render_sync_viewport_cb.as_ref() else {
+            let Some(immediate_viewport_renderer) = immediate_viewport_renderer.as_ref() else {
                 // This egui backend does not support multiple viewports.
                 return viewport_ui_cb(self);
             };
@@ -2653,7 +2653,7 @@ impl Context {
                     };
                     ctx.viewports.insert(
                         viewport_builder.id,
-                        Viewport {
+                        ViewportState {
                             builder: viewport_builder.clone(),
                             id_pair,
                             used: true,
@@ -2668,7 +2668,7 @@ impl Context {
             {
                 let out = &mut out;
 
-                render_sync_viewport_cb(
+                immediate_viewport_renderer(
                     self,
                     viewport_builder,
                     id_pair,

crates/egui/src/viewport.rs

@@ -17,13 +17,12 @@ use crate::{Context, Id};
 
 /// A unique identifier of a viewport.
 ///
-/// Generated by [`Context`].
-///
 /// This is returned by [`Context::viewport_id`] and [`Context::parent_viewport_id`].
 #[derive(Clone, Copy, Hash, PartialEq, Eq)]
 pub struct ViewportId(pub Id);
 
 impl Default for ViewportId {
+    #[inline]
     fn default() -> Self {
         Self::ROOT
     }
@@ -39,6 +38,7 @@ impl ViewportId {
     /// The `ViewportId` of the root viewport.
     pub const ROOT: Self = Self(Id::null());
 
+    #[inline]
     pub fn from_hash_of(source: impl std::hash::Hash) -> Self {
         Self(Id::new(source))
     }
@@ -61,7 +61,7 @@ pub type ViewportIdMap<T> = nohash_hasher::IntMap<ViewportId, T>;
 
 // ----------------------------------------------------------------------------
 
-/// This will deref to [`Self::this`].
+/// A pair of [`ViewportId`], used to identify a viewport and its parent.
 #[derive(Debug, Hash, Clone, Copy, PartialEq, Eq)]
 pub struct ViewportIdPair {
     pub this: ViewportId,
@@ -69,11 +69,9 @@ pub struct ViewportIdPair {
 }
 
 impl Default for ViewportIdPair {
+    #[inline]
     fn default() -> Self {
-        Self {
+        Self::ROOT
-            this: ViewportId::ROOT,
-            parent: ViewportId::ROOT,
-        }
     }
 }
 
@@ -89,7 +87,7 @@ impl ViewportIdPair {
 pub type ViewportUiCallback = dyn Fn(&Context) + Sync + Send;
 
 /// Render the given viewport, calling the given ui callback.
-pub type ViewportRenderSyncCallback =
+pub type ImmediateViewportRendererCallback =
     dyn for<'a> Fn(&Context, ViewportBuilder, ViewportIdPair, Box<dyn FnOnce(&Context) + 'a>);
 
 /// Control the building of a new egui viewport (i.e. native window).
@@ -403,6 +401,8 @@ impl ViewportBuilder {
         self
     }
 
+    /// Update this `ViewportBuilder` with a delta,
+    /// returning a list of commands and a bool intdicating if the window needs to be recreated.
     pub fn patch(&mut self, new: &ViewportBuilder) -> (Vec<ViewportCommand>, bool) {
         let mut commands = Vec::new();
 
@@ -648,7 +648,7 @@ pub enum ViewportCommand {
 }
 
 #[derive(Clone)]
-pub(crate) struct Viewport {
+pub(crate) struct ViewportState {
     pub(crate) builder: ViewportBuilder,
 
     /// Id of us and our parent.
@@ -663,6 +663,7 @@ pub(crate) struct Viewport {
     pub(crate) viewport_ui_cb: Option<Arc<Box<ViewportUiCallback>>>,
 }
 
+/// Describes a viewport, i.e. a native window.
 #[derive(Clone)]
 pub struct ViewportOutput {
     pub builder: ViewportBuilder,
@@ -672,6 +673,6 @@ pub struct ViewportOutput {
 
     /// The user-code that shows the GUI, used for deferred viewports.
     ///
-    /// `None` for immediate viewports.
+    /// `None` for immediate viewports and the ROOT viewport.
     pub viewport_ui_cb: Option<Arc<Box<ViewportUiCallback>>>,
 }

crates/egui_glow/src/winit.rs

@@ -45,8 +45,6 @@ impl EguiGlow {
         self.egui_winit.on_event(&self.egui_ctx, event)
     }
 
-    /// Returns the `Duration` of the timeout after which egui should be repainted even if there's no new events.
-    ///
     /// Call [`Self::paint`] later to paint.
     pub fn run(&mut self, window: &winit::window::Window, run_ui: impl FnMut(&egui::Context)) {
         let raw_input = self.egui_winit.take_egui_input(window);