Allow hiding top panel via blueprint (#6409)

### What

- `rrb.TopPanel` is now exposed, works similarly to `rrb.TimePanel`
- `TimePanel` hidden state now fully hides the time panel

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested the web demo (if applicable):
* Using examples from latest `main` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6409?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[rerun.io/viewer](https://rerun.io/viewer/pr/6409?manifest_url=https://app.rerun.io/version/nightly/examples_manifest.json)
* [x] The PR title and labels are set such as to maximize their
usefulness for the next release's CHANGELOG
* [x] If applicable, add a new check to the [release
checklist](https://github.com/rerun-io/rerun/blob/main/tests/python/release_checklist)!

- [PR Build Summary](https://build.rerun.io/pr/6409)
- [Recent benchmark results](https://build.rerun.io/graphs/crates.html)
- [Wasm size tracking](https://build.rerun.io/graphs/sizes.html)

To run all checks from `main`, comment on the PR with `@rerun-bot
full-check`.

---------

Co-authored-by: Andreas Reich <andreas@rerun.io>

crates/re_time_panel/src/lib.rs

@@ -147,6 +147,10 @@ impl TimePanel {
         ui: &mut egui::Ui,
         state: PanelState,
     ) {
+        if state == PanelState::Hidden {
+            return;
+        }
+
         // Naturally, many parts of the time panel need the time control.
         // Copy it once, read/edit, and then write back at the end if there was a change.
         let time_ctrl_before = rec_cfg.time_ctrl.read().clone();

crates/re_viewer/src/app.rs

@@ -4,7 +4,6 @@ use re_entity_db::entity_db::EntityDb;
 use re_log_types::{ApplicationId, FileSource, LogMsg, StoreKind};
 use re_renderer::WgpuResourcePoolStatistics;
 use re_smart_channel::{ReceiveSet, SmartChannelSource};
-use re_types::blueprint::components::PanelState;
 use re_ui::{toasts, UICommand, UICommandSender};
 use re_viewer_context::{
     command_channel,
@@ -884,16 +883,14 @@ impl App {
 
                 crate::ui::mobile_warning_ui(&self.re_ui, ui);
 
-                if app_blueprint.top_panel_state != PanelState::Hidden {
-                    crate::ui::top_panel(
-                        frame,
-                        self,
-                        app_blueprint,
-                        store_context,
-                        gpu_resource_stats,
-                        ui,
-                    );
-                }
+                crate::ui::top_panel(
+                    frame,
+                    self,
+                    app_blueprint,
+                    store_context,
+                    gpu_resource_stats,
+                    ui,
+                );
 
                 self.memory_panel_ui(ui, gpu_resource_stats, store_stats);
 

crates/re_viewer/src/ui/top_panel.rs

@@ -20,34 +20,33 @@ pub fn top_panel(
 
     let style_like_web = app.is_screenshotting();
     let top_bar_style = app.re_ui().top_bar_style(style_like_web);
-
-    egui::TopBottomPanel::top("top_bar")
-        .frame(app.re_ui().top_panel_frame())
-        .exact_height(top_bar_style.height)
-        .show_inside(ui, |ui| {
-            // React to dragging and double-clicking the top bar:
-            #[cfg(not(target_arch = "wasm32"))]
-            if !re_ui::NATIVE_WINDOW_BAR {
-                // Interact with background first, so that buttons in the top bar gets input priority
-                // (last added widget has priority for input).
-                let title_bar_response = ui.interact(
-                    ui.max_rect(),
-                    ui.id().with("background"),
-                    egui::Sense::click(),
-                );
-                if title_bar_response.double_clicked() {
-                    let maximized = ui.input(|i| i.viewport().maximized.unwrap_or(false));
-                    ui.ctx()
-                        .send_viewport_cmd(egui::ViewportCommand::Maximized(!maximized));
-                } else if title_bar_response.is_pointer_button_down_on() {
-                    ui.ctx().send_viewport_cmd(egui::ViewportCommand::StartDrag);
-                }
+    let top_panel_frame = app.re_ui().top_panel_frame();
+
+    let mut content = |ui: &mut egui::Ui, show_content: bool| {
+        // React to dragging and double-clicking the top bar:
+        #[cfg(not(target_arch = "wasm32"))]
+        if !re_ui::NATIVE_WINDOW_BAR {
+            // Interact with background first, so that buttons in the top bar gets input priority
+            // (last added widget has priority for input).
+            let title_bar_response = ui.interact(
+                ui.max_rect(),
+                ui.id().with("background"),
+                egui::Sense::click(),
+            );
+            if title_bar_response.double_clicked() {
+                let maximized = ui.input(|i| i.viewport().maximized.unwrap_or(false));
+                ui.ctx()
+                    .send_viewport_cmd(egui::ViewportCommand::Maximized(!maximized));
+            } else if title_bar_response.is_pointer_button_down_on() {
+                ui.ctx().send_viewport_cmd(egui::ViewportCommand::StartDrag);
             }
+        }
 
-            egui::menu::bar(ui, |ui| {
-                ui.set_height(top_bar_style.height);
-                ui.add_space(top_bar_style.indent);
+        egui::menu::bar(ui, |ui| {
+            ui.set_height(top_bar_style.height);
+            ui.add_space(top_bar_style.indent);
 
+            if show_content {
                 top_bar_ui(
                     frame,
                     app,
@@ -56,8 +55,22 @@ pub fn top_panel(
                     ui,
                     gpu_resource_stats,
                 );
-            });
+            }
         });
+    };
+
+    let panel = egui::TopBottomPanel::top("top_bar")
+        .frame(top_panel_frame)
+        .exact_height(top_bar_style.height);
+    let is_expanded = app_blueprint.top_panel_state.is_expanded();
+
+    // On MacOS, we show the close/minimize/maximize buttons in the top panel.
+    // We _always_ want to show the top panel in that case, and only hide its content.
+    if !re_ui::NATIVE_WINDOW_BAR {
+        panel.show_inside(ui, |ui| content(ui, is_expanded));
+    } else {
+        panel.show_animated_inside(ui, is_expanded, |ui| content(ui, is_expanded));
+    }
 }
 
 fn top_bar_ui(

rerun_py/rerun_sdk/rerun/blueprint/api.py

@@ -317,6 +317,8 @@ def __init__(self, *, expanded: bool | None = None, state: PanelStateLike | None
         state:
             Whether the panel is expanded, collapsed, or hidden.
 
+            Collapsed and hidden both fully hide the top panel.
+
         """
         super().__init__(blueprint_path="top_panel", expanded=expanded, state=state)
 
@@ -335,6 +337,8 @@ def __init__(self, *, expanded: bool | None = None, state: PanelStateLike | None
         state:
             Whether the panel is expanded, collapsed, or hidden.
 
+            Collapsed and hidden both fully hide the blueprint panel.
+
         """
         super().__init__(blueprint_path="blueprint_panel", expanded=expanded, state=state)
 
@@ -353,6 +357,8 @@ def __init__(self, *, expanded: bool | None = None, state: PanelStateLike | None
         state:
             Whether the panel is expanded, collapsed, or hidden.
 
+            Collapsed and hidden both fully hide the selection panel.
+
         """
         super().__init__(blueprint_path="selection_panel", expanded=expanded, state=state)
 
@@ -371,6 +377,9 @@ def __init__(self, *, expanded: bool | None = None, state: PanelStateLike | None
         state:
             Whether the panel is expanded, collapsed, or hidden.
 
+            Expanded fully shows the panel, collapsed shows a simplified panel,
+            hidden fully hides the panel.
+
         """
         super().__init__(blueprint_path="time_panel", expanded=expanded, state=state)
 
@@ -383,7 +392,7 @@ def __init__(self, *, expanded: bool | None = None, state: PanelStateLike | None
 helper classes.
 """
 
-BlueprintPart = Union[ContainerLike, BlueprintPanel, SelectionPanel, TimePanel]
+BlueprintPart = Union[ContainerLike, TopPanel, BlueprintPanel, SelectionPanel, TimePanel]
 """
 The types that make up a blueprint.
 """
@@ -430,7 +439,9 @@ def __init__(
             Defaults to `False` unless no Containers or SpaceViews are provided, in which case it defaults to `True`.
             If you want to create a completely empty Blueprint, you must explicitly set this to `False`.
         collapse_panels:
-            Whether to collapse the panels in the viewer. Defaults to `False`.
+            Whether to collapse panels in the viewer. Defaults to `False`.
+
+            This fully hides the blueprint/selection panels, and shows the simplified time panel.
 
         """
         from .containers import Tabs
@@ -442,6 +453,10 @@ def __init__(
         for part in parts:
             if isinstance(part, (Container, SpaceView)):
                 contents.append(part)
+            elif isinstance(part, TopPanel):
+                if hasattr(self, "top_panel"):
+                    raise ValueError("Only one top panel can be provided")
+                self.top_panel = part
             elif isinstance(part, BlueprintPanel):
                 if hasattr(self, "blueprint_panel"):
                     raise ValueError("Only one blueprint panel can be provided")
@@ -492,6 +507,9 @@ def _log_to_stream(self, stream: RecordingStream) -> None:
 
         stream.log("viewport", viewport_arch)  # type: ignore[attr-defined]
 
+        if hasattr(self, "top_panel"):
+            self.top_panel._log_to_stream(stream)
+
         if hasattr(self, "blueprint_panel"):
             self.blueprint_panel._log_to_stream(stream)
         elif self.collapse_panels: