Remove id from ViewportBuilder so it can implement Default

crates/eframe/src/native/epi_integration.rs

@@ -85,10 +85,9 @@ pub fn window_builder<E>(
         ..
     } = native_options;
 
-    let mut viewport_builder = egui::ViewportBuilder::new(ViewportId::ROOT);
+    let mut viewport_builder = egui::ViewportBuilder::ROOT;
     viewport_builder
         .with_title(title)
-        .with_close_button(true) // The default for all other viewports is `false`!
         .with_decorations(*decorated)
         .with_fullscreen(*fullscreen)
         .with_maximized(*maximized)

crates/egui/src/context.rs

@@ -2554,6 +2554,8 @@ impl Context {
 
     /// This creates a new native window, if possible.
     ///
+    /// The given id must be unique for each viewport.
+    ///
     /// You need to call this each frame when the child viewport should exist.
     ///
     /// The given callback will be called whenever the child viewport needs repainting,
@@ -2573,7 +2575,8 @@ impl Context {
     /// `ctx.viewport_id() != ctx.parent_viewport_id` if false you should create a [`crate::Window`].
     pub fn show_viewport(
         &self,
-        viewport_builder: &ViewportBuilder,
+        new_viewport_id: ViewportId,
+        viewport_builder: ViewportBuilder,
         viewport_ui_cb: impl Fn(&Context) + Send + Sync + 'static,
     ) {
         crate::profile_function!();
@@ -2582,21 +2585,21 @@ impl Context {
             viewport_ui_cb(self);
         } else {
             self.write(|ctx| {
-                let viewport_id = ctx.viewport_id();
+                let parent_viewport_id = ctx.viewport_id();
-                if let Some(window) = ctx.viewports.get_mut(&viewport_builder.id) {
+                if let Some(window) = ctx.viewports.get_mut(&new_viewport_id) {
-                    window.builder = viewport_builder.clone();
+                    window.builder = viewport_builder;
-                    window.ids.parent = viewport_id;
+                    window.ids.parent = parent_viewport_id;
                     window.used = true;
                     window.viewport_ui_cb = Some(Arc::new(Box::new(viewport_ui_cb)));
                 } else {
                     ctx.viewports.insert(
-                        viewport_builder.id,
+                        new_viewport_id,
                         ViewportState {
                             ids: ViewportIdPair {
-                                this: viewport_builder.id,
+                                this: new_viewport_id,
-                                parent: viewport_id,
+                                parent: parent_viewport_id,
                             },
-                            builder: viewport_builder.clone(),
+                            builder: viewport_builder,
                             used: true,
                             viewport_ui_cb: Some(Arc::new(Box::new(viewport_ui_cb))),
                         },
@@ -2608,6 +2611,8 @@ impl Context {
 
     /// This creates a new native window, if possible.
     ///
+    /// The given id must be unique for each viewport.
+    ///
     /// You need to call this each frame when the child viewport should exist.
     ///
     /// The given ui function will be called immediately.
@@ -2626,6 +2631,7 @@ impl Context {
     /// `ctx.viewport_id() != ctx.parent_viewport_id` if false you should create a [`crate::Window`].
     pub fn show_viewport_immediate<T>(
         &self,
+        new_viewport_id: ViewportId,
         builder: ViewportBuilder,
         viewport_ui_cb: impl FnOnce(&Context) -> T,
     ) -> T {
@@ -2643,23 +2649,23 @@ impl Context {
             };
 
             let ids = self.write(|ctx| {
-                let parent = ctx.viewport_id();
+                let parent_viewport_id = ctx.viewport_id();
 
-                if let Some(window) = ctx.viewports.get_mut(&builder.id) {
+                if let Some(window) = ctx.viewports.get_mut(&new_viewport_id) {
                     // Existing
                     window.builder = builder.clone();
-                    window.ids.parent = parent;
+                    window.ids.parent = parent_viewport_id;
                     window.used = true;
                     window.viewport_ui_cb = None;
                     window.ids
                 } else {
                     // New
                     let ids = ViewportIdPair {
-                        this: builder.id,
+                        this: new_viewport_id,
-                        parent,
+                        parent: parent_viewport_id,
                     };
                     ctx.viewports.insert(
-                        builder.id,
+                        new_viewport_id,
                         ViewportState {
                             builder: builder.clone(),
                             ids,

crates/egui/src/viewport.rs

@@ -99,11 +99,9 @@ pub type ImmediateViewportRendererCallback = dyn for<'a> Fn(&Context, ImmediateV
 /// Since egui is immediate mode, `ViewportBuilder` is accumulative in nature.
 /// Setting any option to `None` means "keep the current value",
 /// or "Use the default" if it is the first call.
-#[derive(PartialEq, Eq, Clone)]
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
 #[allow(clippy::option_option)]
 pub struct ViewportBuilder {
-    pub id: ViewportId,
-
     /// The title of the vieweport.
     /// `eframe` will use this as the title of the native window.
     pub title: Option<String>,
@@ -136,36 +134,37 @@ pub struct ViewportBuilder {
 }
 
 impl ViewportBuilder {
+    /// Default settings for the root viewport.
+    pub const ROOT: Self = Self {
+        title: None,
+        name: None,
+        position: None,
+        inner_size: Some(Some(Vec2::new(300.0, 200.0))),
+        fullscreen: None,
+        maximized: None,
+        resizable: Some(true),
+        transparent: Some(true),
+        decorations: Some(true),
+        icon: None,
+        active: Some(true),
+        visible: Some(true),
+        title_hidden: None,
+        titlebar_transparent: None,
+        fullsize_content_view: None,
+        min_inner_size: None,
+        max_inner_size: None,
+        drag_and_drop: Some(true),
+        close_button: Some(false), // We disable the close button by default because we haven't implemented closing of child viewports yet
+        minimize_button: Some(true),
+        maximize_button: Some(true),
+        hittest: Some(true),
+    };
+
     /// Default settings for a new child viewport.
-    ///
+    pub const CHILD: Self = Self {
-    /// The given id must be unique for each viewport.
+        close_button: Some(false), // We disable the close button by default because we haven't implemented closing of child viewports yet
-    pub fn new(id: ViewportId) -> Self {
+        ..Self::ROOT
-        Self {
+    };
-            id,
-            title: None,
-            name: None,
-            position: None,
-            inner_size: Some(Some(Vec2::new(300.0, 200.0))),
-            fullscreen: None,
-            maximized: None,
-            resizable: Some(true),
-            transparent: Some(true),
-            decorations: Some(true),
-            icon: None,
-            active: Some(true),
-            visible: Some(true),
-            title_hidden: None,
-            titlebar_transparent: None,
-            fullsize_content_view: None,
-            min_inner_size: None,
-            max_inner_size: None,
-            drag_and_drop: Some(true),
-            close_button: Some(false), // We disable the close button by default because we haven't implemented closing of child viewports yet
-            minimize_button: Some(true),
-            maximize_button: Some(true),
-            hittest: Some(true),
-        }
-    }
 
     /// Empty settings for everything.
     ///
@@ -173,33 +172,30 @@ impl ViewportBuilder {
     /// When used on subsequent frames, the current settings will be kept.
     ///
     /// The given id must be unique for each viewport.
-    pub fn empty(id: ViewportId) -> Self {
+    pub const EMPTY: Self = Self {
-        Self {
+        title: None,
-            id,
+        name: None,
-            title: None,
+        position: None,
-            name: None,
+        inner_size: None,
-            position: None,
+        fullscreen: None,
-            inner_size: None,
+        maximized: None,
-            fullscreen: None,
+        resizable: None,
-            maximized: None,
+        transparent: None,
-            resizable: None,
+        decorations: None,
-            transparent: None,
+        icon: None,
-            decorations: None,
+        active: None,
-            icon: None,
+        visible: None,
-            active: None,
+        title_hidden: None,
-            visible: None,
+        titlebar_transparent: None,
-            title_hidden: None,
+        fullsize_content_view: None,
-            titlebar_transparent: None,
+        min_inner_size: None,
-            fullsize_content_view: None,
+        max_inner_size: None,
-            min_inner_size: None,
+        drag_and_drop: None,
-            max_inner_size: None,
+        close_button: None,
-            drag_and_drop: None,
+        minimize_button: None,
-            close_button: None,
+        maximize_button: None,
-            minimize_button: None,
+        hittest: None,
-            maximize_button: None,
+    };
-            hittest: None,
-        }
-    }
 
     /// Sets the initial title of the window in the title bar.
     ///

crates/epaint/src/image.rs

@@ -238,6 +238,15 @@ impl From<Arc<ColorImage>> for ImageData {
     }
 }
 
+impl std::fmt::Debug for ColorImage {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("ColorImage")
+            .field("size", &self.size)
+            .field("pixel-count", &self.pixels.len())
+            .finish_non_exhaustive()
+    }
+}
+
 // ----------------------------------------------------------------------------
 
 /// A single-channel image designed for the font texture.

examples/multiple_viewports/src/main.rs

@@ -28,10 +28,13 @@ impl eframe::App for MyApp {
             ui.checkbox(&mut self.show_child_viewport, "Show secondary viewport");
         });
 
+        let mut viewport = egui::ViewportBuilder::CHILD;
+        viewport.with_title("Secondary Viewport");
+
         if self.show_child_viewport {
             ctx.show_viewport(
-                egui::ViewportBuilder::new(egui::ViewportId::from_hash_of("secondary_viewport"))
+                egui::ViewportId::from_hash_of("secondary_viewport"),
-                    .with_title("Secondary Viewport"),
+                viewport,
                 |ctx| {
                     egui::CentralPanel::default().show(ctx, |ui| {
                         ui.label("Hello from secondary viewport");

examples/test_viewports/src/main.rs

@@ -65,21 +65,21 @@ impl ViewportState {
         let immediate = vp_state.read().immediate;
         let title = vp_state.read().title.clone();
 
-        let mut vp_builder = ViewportBuilder::new(vp_id);
+        let mut vp_builder = ViewportBuilder::ROOT;
         vp_builder
             .with_title(&title)
             .with_inner_size(Some(egui::vec2(450.0, 400.0)));
 
         if immediate {
             let mut vp_state = vp_state.write();
-            ctx.show_viewport_immediate(vp_builder, move |ctx| {
+            ctx.show_viewport_immediate(vp_id, vp_builder, move |ctx| {
                 show_as_popup(ctx, &title, vp_id.into(), |ui: &mut egui::Ui| {
                     generic_child_ui(ui, &mut vp_state);
                 });
             });
         } else {
             let count = Arc::new(RwLock::new(0));
-            ctx.show_viewport(&vp_builder, move |ctx| {
+            ctx.show_viewport(vp_id, vp_builder, move |ctx| {
                 let mut vp_state = vp_state.write();
                 let count = count.clone();
                 show_as_popup(ctx, &title, vp_id.into(), move |ui: &mut egui::Ui| {