Hide entity icons in paths (#5550)

### What
* Closes #5524

Before:
<img width="447" alt="image"
src="https://github.com/rerun-io/rerun/assets/1148717/4a92a481-2185-41a4-b2b0-15a63c41e060">


After:
<img width="374" alt="image"
src="https://github.com/rerun-io/rerun/assets/1148717/1d2942e3-bb19-4a80-a5c0-7422101f7560">


### 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 newly built examples:
[app.rerun.io](https://app.rerun.io/pr/5550/index.html)
* Using examples from latest `main` build:
[app.rerun.io](https://app.rerun.io/pr/5550/index.html?manifest_url=https://app.rerun.io/version/main/examples_manifest.json)
* Using full set of examples from `nightly` build:
[app.rerun.io](https://app.rerun.io/pr/5550/index.html?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/5550)
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preview](https://rerun.io/preview/93e90e8c6e8e8df6093eabdf129d7061dab0d1a8/docs)
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crates/re_data_ui/src/item_ui.rs

@@ -3,7 +3,6 @@
 //! TODO(andreas): This is not a `data_ui`, can this go somewhere else, shouldn't be in `re_data_ui`.
 
 use re_entity_db::{EntityTree, InstancePath};
-use re_log_types::external::re_types_core::components::InstanceKey;
 use re_log_types::{ComponentPath, EntityPath, TimeInt, Timeline};
 use re_ui::SyntaxHighlighting;
 use re_viewer_context::{HoverHighlight, Item, SpaceViewId, UiVerbosity, ViewerContext};
@@ -62,22 +61,29 @@ pub fn entity_path_parts_buttons(
     space_view_id: Option<SpaceViewId>,
     entity_path: &EntityPath,
 ) -> egui::Response {
+    let with_icon = false; // too much noise with icons in a path
+
     ui.horizontal(|ui| {
-        ui.spacing_mut().item_spacing.x = 4.0;
+        ui.spacing_mut().item_spacing.x = 2.0;
+
+        // Show one single icon up-front instead:
+        let instance_path = InstancePath::entity_splat(entity_path.clone());
+        ui.add(instance_path_icon(&query.timeline, store, &instance_path).as_image());
 
         let mut accumulated = Vec::new();
         for part in entity_path.iter() {
             accumulated.push(part.clone());
 
             ui.strong("/");
-            entity_path_button_to(
+            instance_path_button_to_ex(
                 ctx,
                 query,
                 store,
                 ui,
                 space_view_id,
-                &accumulated.clone().into(),
+                &InstancePath::entity_splat(accumulated.clone().into()),
                 part.syntax_highlighted(ui.style()),
+                with_icon,
             );
         }
     })
@@ -134,17 +140,19 @@ pub fn instance_path_icon(
     store: &re_data_store::DataStore,
     instance_path: &InstancePath,
 ) -> &'static re_ui::icons::Icon {
-    if instance_path.instance_key != InstanceKey::SPLAT {
-        return &re_ui::icons::ENTITY;
-    }
-
-    if store
-        .all_components(timeline, &instance_path.entity_path)
-        .is_some()
-    {
-        &re_ui::icons::ENTITY
+    if instance_path.is_splat() {
+        // It is an entity path
+        if store
+            .all_components(timeline, &instance_path.entity_path)
+            .is_some()
+        {
+            &re_ui::icons::ENTITY
+        } else {
+            &re_ui::icons::ENTITY_EMPTY
+        }
     } else {
-        &re_ui::icons::ENTITY_EMPTY
+        // An instance path
+        &re_ui::icons::ENTITY
     }
 }
 
@@ -190,25 +198,52 @@ pub fn instance_path_button_to(
     space_view_id: Option<SpaceViewId>,
     instance_path: &InstancePath,
     text: impl Into<egui::WidgetText>,
+) -> egui::Response {
+    instance_path_button_to_ex(
+        ctx,
+        query,
+        store,
+        ui,
+        space_view_id,
+        instance_path,
+        text,
+        true,
+    )
+}
+
+/// Show an instance id and make it selectable.
+#[allow(clippy::too_many_arguments)]
+fn instance_path_button_to_ex(
+    ctx: &ViewerContext<'_>,
+    query: &re_data_store::LatestAtQuery,
+    store: &re_data_store::DataStore,
+    ui: &mut egui::Ui,
+    space_view_id: Option<SpaceViewId>,
+    instance_path: &InstancePath,
+    text: impl Into<egui::WidgetText>,
+    with_icon: bool,
 ) -> egui::Response {
     let item = if let Some(space_view_id) = space_view_id {
         Item::DataResult(space_view_id, instance_path.clone())
     } else {
         Item::InstancePath(instance_path.clone())
     };
 
-    let response = ctx
-        .re_ui
-        .selectable_label_with_icon(
+    let response = if with_icon {
+        ctx.re_ui.selectable_label_with_icon(
             ui,
             instance_path_icon(&query.timeline, store, instance_path),
             text,
             ctx.selection().contains_item(&item),
             re_ui::LabelStyle::Normal,
         )
-        .on_hover_ui(|ui| {
-            instance_hover_card_ui(ui, ctx, query, store, instance_path);
-        });
+    } else {
+        ui.selectable_label(ctx.selection().contains_item(&item), text)
+    };
+
+    let response = response.on_hover_ui(|ui| {
+        instance_hover_card_ui(ui, ctx, query, store, instance_path);
+    });
 
     cursor_interact_with_selectable(ctx, response, item)
 }
@@ -222,35 +257,42 @@ pub fn instance_path_parts_buttons(
     space_view_id: Option<SpaceViewId>,
     instance_path: &InstancePath,
 ) -> egui::Response {
+    let with_icon = false; // too much noise with icons in a path
+
     ui.horizontal(|ui| {
-        ui.spacing_mut().item_spacing.x = 4.0;
+        ui.spacing_mut().item_spacing.x = 2.0;
+
+        // Show one single icon up-front instead:
+        ui.add(instance_path_icon(&query.timeline, store, instance_path).as_image());
 
         let mut accumulated = Vec::new();
         for part in instance_path.entity_path.iter() {
             accumulated.push(part.clone());
 
             ui.strong("/");
-            entity_path_button_to(
+            instance_path_button_to_ex(
                 ctx,
                 query,
                 store,
                 ui,
                 space_view_id,
-                &accumulated.clone().into(),
+                &InstancePath::entity_splat(accumulated.clone().into()),
                 part.syntax_highlighted(ui.style()),
+                with_icon,
             );
         }
 
         if !instance_path.instance_key.is_splat() {
             ui.strong("/");
-            instance_path_button_to(
+            instance_path_button_to_ex(
                 ctx,
                 query,
                 store,
                 ui,
                 space_view_id,
                 instance_path,
                 instance_path.instance_key.syntax_highlighted(ui.style()),
+                with_icon,
             );
         }
     })

crates/re_viewer/src/ui/selection_panel.rs

@@ -316,6 +316,7 @@ fn what_is_selected_ui(
 
             item_title_ui(ctx.re_ui, ui, &title, Some(&re_ui::icons::STORE), &id_str);
         }
+
         Item::Container(container_id) => {
             if let Some(container_blueprint) = viewport.container(container_id) {
                 item_title_ui(
@@ -329,6 +330,7 @@ fn what_is_selected_ui(
                 );
             }
         }
+
         Item::ComponentPath(re_log_types::ComponentPath {
             entity_path,
             component_name,
@@ -354,6 +356,7 @@ fn what_is_selected_ui(
 
             list_existing_data_blueprints(ui, ctx, &entity_path.clone().into(), viewport);
         }
+
         Item::SpaceView(space_view_id) => {
             if let Some(space_view) = viewport.space_view(space_view_id) {
                 let space_view_class = space_view.class(ctx.space_view_class_registry);
@@ -381,20 +384,10 @@ fn what_is_selected_ui(
                     .on_hover_text(hover_text);
             }
         }
-        Item::InstancePath(instance_path) => {
-            let is_instance = !instance_path.instance_key.is_splat();
 
+        Item::InstancePath(instance_path) => {
             let typ = item.kind();
-
-            let (query, store) =
-                guess_query_and_store_for_selected_entity(ctx, &instance_path.entity_path);
-
             let name = instance_path.syntax_highlighted(ui.style());
-            let parent = if is_instance {
-                Some(instance_path.entity_path.clone())
-            } else {
-                instance_path.entity_path.parent()
-            };
 
             item_title_ui(
                 ctx.re_ui,
@@ -404,10 +397,18 @@ fn what_is_selected_ui(
                 &format!("{typ} '{instance_path}'"),
             );
 
+            let is_instance = !instance_path.instance_key.is_splat();
+            let parent = if is_instance {
+                Some(instance_path.entity_path.clone())
+            } else {
+                instance_path.entity_path.parent()
+            };
             if let Some(parent) = parent {
                 if !parent.is_root() {
+                    let (query, store) =
+                        guess_query_and_store_for_selected_entity(ctx, &instance_path.entity_path);
                     ui.horizontal(|ui| {
-                        ui.label("path");
+                        ui.label("Parent");
                         item_ui::entity_path_parts_buttons(ctx, &query, store, ui, None, &parent);
                     });
                 }
@@ -417,21 +418,10 @@ fn what_is_selected_ui(
         }
 
         Item::DataResult(space_view_id, instance_path) => {
-            let is_instance = !instance_path.instance_key.is_splat();
-
-            let typ = item.kind();
-
-            let (query, store) =
-                guess_query_and_store_for_selected_entity(ctx, &instance_path.entity_path);
-
             let name = instance_path.syntax_highlighted(ui.style());
-            let parent = if is_instance {
-                Some(instance_path.entity_path.clone())
-            } else {
-                instance_path.entity_path.parent()
-            };
 
             if let Some(space_view) = viewport.space_view(space_view_id) {
+                let typ = item.kind();
                 item_title_ui(
                     ctx.re_ui,
                     ui,
@@ -443,10 +433,21 @@ fn what_is_selected_ui(
                     ),
                 );
 
+                let is_instance = !instance_path.instance_key.is_splat();
+                let parent = if is_instance {
+                    Some(instance_path.entity_path.clone())
+                } else {
+                    instance_path.entity_path.parent()
+                };
                 if let Some(parent) = parent {
                     if !parent.is_root() {
                         ui.horizontal(|ui| {
-                            ui.label("path");
+                            let (query, store) = guess_query_and_store_for_selected_entity(
+                                ctx,
+                                &instance_path.entity_path,
+                            );
+
+                            ui.label("Parent");
                             item_ui::entity_path_parts_buttons(
                                 ctx,
                                 &query,