Typename cleanup in SpaceViewClass framework (#2321)

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### What

`SpaceViewClass` -> `DynSpaceViewClass`
`SpaceViewClassImpl` -> `SpaceViewClass`
As well as rename of associated types on `SpaceViewClass`(Impl) to be
less confusing.

### 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)

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PR Build Summary: https://build.rerun.io/pr/2321

<!-- pr-link-docs:start -->
Docs preview: https://rerun.io/preview/c7708cd/docs
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crates/re_space_view_spatial/src/space_view_class.rs

@@ -1,6 +1,6 @@
 use nohash_hasher::IntSet;
 use re_log_types::EntityPath;
-use re_viewer_context::{SpaceViewClassImpl, SpaceViewId};
+use re_viewer_context::{SpaceViewClass, SpaceViewId};
 
 use crate::{
     scene::{SpatialSceneContext, SpatialScenePartCollection, SpatialScenePartData},
@@ -10,10 +10,10 @@ use crate::{
 #[derive(Default)]
 pub struct SpatialSpaceView;
 
-impl SpaceViewClassImpl for SpatialSpaceView {
-    type SpaceViewState = SpatialSpaceViewState;
-    type SceneContext = SpatialSceneContext;
-    type ScenePartCollection = SpatialScenePartCollection;
+impl SpaceViewClass for SpatialSpaceView {
+    type State = SpatialSpaceViewState;
+    type Context = SpatialSceneContext;
+    type SceneParts = SpatialScenePartCollection;
     type ScenePartData = SpatialScenePartData;
 
     fn name(&self) -> re_viewer_context::SpaceViewClassName {
@@ -24,11 +24,11 @@ impl SpaceViewClassImpl for SpatialSpaceView {
         &re_ui::icons::SPACE_VIEW_3D
     }
 
-    fn help_text(&self, re_ui: &re_ui::ReUi, state: &Self::SpaceViewState) -> egui::WidgetText {
+    fn help_text(&self, re_ui: &re_ui::ReUi, state: &Self::State) -> egui::WidgetText {
         state.help_text(re_ui)
     }
 
-    fn preferred_tile_aspect_ratio(&self, state: &Self::SpaceViewState) -> Option<f32> {
+    fn preferred_tile_aspect_ratio(&self, state: &Self::State) -> Option<f32> {
         match state.nav_mode.get() {
             SpatialNavigationMode::TwoD => {
                 let size = state.scene_bbox_accum.size();
@@ -41,7 +41,7 @@ impl SpaceViewClassImpl for SpatialSpaceView {
     fn prepare_populate(
         &self,
         ctx: &mut re_viewer_context::ViewerContext<'_>,
-        state: &Self::SpaceViewState,
+        state: &Self::State,
         entity_paths: &IntSet<EntityPath>,
         entity_properties: &mut re_data_store::EntityPropertyMap,
     ) {
@@ -52,7 +52,7 @@ impl SpaceViewClassImpl for SpatialSpaceView {
         &self,
         ctx: &mut re_viewer_context::ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         space_origin: &EntityPath,
         space_view_id: SpaceViewId,
     ) {
@@ -63,7 +63,7 @@ impl SpaceViewClassImpl for SpatialSpaceView {
         &self,
         ctx: &mut re_viewer_context::ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         scene: &mut re_viewer_context::TypedScene<Self>,
         space_origin: &EntityPath,
         space_view_id: SpaceViewId,

crates/re_space_view_text/src/scene_part.rs

@@ -3,7 +3,7 @@ use re_data_store::EntityPath;
 use re_log_types::{Component as _, InstanceKey, RowId};
 use re_query::{range_entity_with_primary, QueryError};
 use re_viewer_context::{
-    ArchetypeDefinition, ScenePart, ScenePartCollection, SceneQuery, SpaceViewClassImpl,
+    ArchetypeDefinition, ScenePart, ScenePartCollection, SceneQuery, SpaceViewClass,
     SpaceViewHighlights, ViewerContext,
 };
 
@@ -51,8 +51,8 @@ impl ScenePart<TextSpaceView> for SceneText {
         &mut self,
         ctx: &mut ViewerContext<'_>,
         query: &SceneQuery<'_>,
-        state: &<TextSpaceView as SpaceViewClassImpl>::SpaceViewState,
-        _scene_context: &<TextSpaceView as SpaceViewClassImpl>::SceneContext,
+        state: &<TextSpaceView as SpaceViewClass>::State,
+        _scene_context: &<TextSpaceView as SpaceViewClass>::Context,
         _highlights: &SpaceViewHighlights,
     ) -> Vec<re_renderer::QueueableDrawData> {
         let store = &ctx.store_db.entity_db.data_store;

crates/re_space_view_text/src/space_view_class.rs

@@ -3,7 +3,7 @@ use std::collections::BTreeMap;
 use re_data_ui::item_ui;
 use re_log_types::{EntityPath, TimePoint, Timeline};
 use re_viewer_context::{
-    level_to_rich_text, SpaceViewClassImpl, SpaceViewClassName, SpaceViewId, SpaceViewState,
+    level_to_rich_text, SpaceViewClass, SpaceViewClassName, SpaceViewId, SpaceViewState,
     TypedScene, ViewerContext,
 };
 
@@ -36,10 +36,10 @@ impl SpaceViewState for TextSpaceViewState {
 #[derive(Default)]
 pub struct TextSpaceView;
 
-impl SpaceViewClassImpl for TextSpaceView {
-    type SpaceViewState = TextSpaceViewState;
-    type SceneContext = re_space_view::EmptySceneContext;
-    type ScenePartCollection = SceneText;
+impl SpaceViewClass for TextSpaceView {
+    type State = TextSpaceViewState;
+    type Context = re_space_view::EmptySceneContext;
+    type SceneParts = SceneText;
     type ScenePartData = ();
 
     fn name(&self) -> SpaceViewClassName {
@@ -50,19 +50,19 @@ impl SpaceViewClassImpl for TextSpaceView {
         &re_ui::icons::SPACE_VIEW_TEXTBOX
     }
 
-    fn help_text(&self, _re_ui: &re_ui::ReUi, _state: &Self::SpaceViewState) -> egui::WidgetText {
+    fn help_text(&self, _re_ui: &re_ui::ReUi, _state: &Self::State) -> egui::WidgetText {
         "Shows text entries over time.\nSelect the Space View for filtering options.".into()
     }
 
-    fn preferred_tile_aspect_ratio(&self, _state: &Self::SpaceViewState) -> Option<f32> {
+    fn preferred_tile_aspect_ratio(&self, _state: &Self::State) -> Option<f32> {
         Some(2.0) // Make text logs wide
     }
 
     fn selection_ui(
         &self,
         ctx: &mut ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         _space_origin: &EntityPath,
         _space_view_id: SpaceViewId,
     ) {
@@ -114,7 +114,7 @@ impl SpaceViewClassImpl for TextSpaceView {
         &self,
         ctx: &mut ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         scene: &mut TypedScene<Self>,
         _space_origin: &EntityPath,
         _space_view_id: SpaceViewId,

crates/re_space_view_text_box/src/scene_part.rs

@@ -2,7 +2,7 @@ use re_arrow_store::LatestAtQuery;
 use re_components::Component;
 use re_query::{query_entity_with_primary, QueryError};
 use re_viewer_context::{
-    ArchetypeDefinition, ScenePart, ScenePartCollection, SceneQuery, SpaceViewClassImpl,
+    ArchetypeDefinition, ScenePart, ScenePartCollection, SceneQuery, SpaceViewClass,
     SpaceViewHighlights, ViewerContext,
 };
 
@@ -40,8 +40,8 @@ impl ScenePart<TextBoxSpaceView> for SceneTextBox {
         &mut self,
         ctx: &mut ViewerContext<'_>,
         query: &SceneQuery<'_>,
-        _space_view_state: &<TextBoxSpaceView as SpaceViewClassImpl>::SpaceViewState,
-        _scene_context: &<TextBoxSpaceView as SpaceViewClassImpl>::SceneContext,
+        _space_view_state: &<TextBoxSpaceView as SpaceViewClass>::State,
+        _scene_context: &<TextBoxSpaceView as SpaceViewClass>::Context,
         _highlights: &SpaceViewHighlights,
     ) -> Vec<re_renderer::QueueableDrawData> {
         let store = &ctx.store_db.entity_db.data_store;

crates/re_space_view_text_box/src/space_view_class.rs

@@ -1,6 +1,6 @@
 use egui::Label;
 use re_viewer_context::{
-    external::re_log_types::EntityPath, SpaceViewClassImpl, SpaceViewClassName, SpaceViewId,
+    external::re_log_types::EntityPath, SpaceViewClass, SpaceViewClassName, SpaceViewId,
     SpaceViewState, TypedScene, ViewerContext,
 };
 
@@ -35,10 +35,10 @@ impl SpaceViewState for TextBoxSpaceViewState {
 #[derive(Default)]
 pub struct TextBoxSpaceView;
 
-impl SpaceViewClassImpl for TextBoxSpaceView {
-    type SpaceViewState = TextBoxSpaceViewState;
-    type ScenePartCollection = SceneTextBox;
-    type SceneContext = re_space_view::EmptySceneContext;
+impl SpaceViewClass for TextBoxSpaceView {
+    type State = TextBoxSpaceViewState;
+    type SceneParts = SceneTextBox;
+    type Context = re_space_view::EmptySceneContext;
     type ScenePartData = ();
 
     fn name(&self) -> SpaceViewClassName {
@@ -49,15 +49,15 @@ impl SpaceViewClassImpl for TextBoxSpaceView {
         &re_ui::icons::SPACE_VIEW_TEXTBOX
     }
 
-    fn help_text(&self, _re_ui: &re_ui::ReUi, _state: &Self::SpaceViewState) -> egui::WidgetText {
+    fn help_text(&self, _re_ui: &re_ui::ReUi, _state: &Self::State) -> egui::WidgetText {
         "Displays text from a text entry components.".into()
     }
 
     fn selection_ui(
         &self,
         ctx: &mut ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         _space_origin: &EntityPath,
         _space_view_id: SpaceViewId,
     ) {
@@ -76,7 +76,7 @@ impl SpaceViewClassImpl for TextBoxSpaceView {
         &self,
         _ctx: &mut ViewerContext<'_>,
         ui: &mut egui::Ui,
-        state: &mut Self::SpaceViewState,
+        state: &mut Self::State,
         scene: &mut TypedScene<Self>,
         _space_origin: &EntityPath,
         _space_view_id: SpaceViewId,

crates/re_viewer/src/app.rs

@@ -8,7 +8,7 @@ use re_renderer::WgpuResourcePoolStatistics;
 use re_smart_channel::Receiver;
 use re_ui::{toasts, Command};
 use re_viewer_context::{
-    AppOptions, ComponentUiRegistry, PlayState, SpaceViewClass, SpaceViewClassRegistry,
+    AppOptions, ComponentUiRegistry, DynSpaceViewClass, PlayState, SpaceViewClassRegistry,
     SpaceViewClassRegistryError,
 };
 
@@ -231,7 +231,7 @@ impl App {
     }
 
     /// Adds a new space view class to the viewer.
-    pub fn add_space_view_class<T: SpaceViewClass + Default + 'static>(
+    pub fn add_space_view_class<T: DynSpaceViewClass + Default + 'static>(
         &mut self,
     ) -> Result<(), SpaceViewClassRegistryError> {
         self.space_view_class_registry.add::<T>()

crates/re_viewer_context/src/lib.rs

@@ -30,8 +30,8 @@ pub use selection_state::{
     HoverHighlight, HoveredSpace, InteractionHighlight, SelectionHighlight, SelectionState,
 };
 pub use space_view::{
-    ArchetypeDefinition, Scene, SceneContext, SceneContextPart, ScenePart, ScenePartCollection,
-    SceneQuery, SpaceViewClass, SpaceViewClassImpl, SpaceViewClassName, SpaceViewClassRegistry,
+    ArchetypeDefinition, DynSpaceViewClass, Scene, SceneContext, SceneContextPart, ScenePart,
+    ScenePartCollection, SceneQuery, SpaceViewClass, SpaceViewClassName, SpaceViewClassRegistry,
     SpaceViewClassRegistryError, SpaceViewEntityHighlight, SpaceViewHighlights,
     SpaceViewOutlineMasks, SpaceViewState, TypedScene,
 };

crates/re_viewer_context/src/space_view/dyn_space_view_class.rs

@@ -0,0 +1,107 @@
+use nohash_hasher::IntSet;
+use re_data_store::EntityPropertyMap;
+use re_log_types::{ComponentName, EntityPath};
+
+use crate::{Scene, SpaceViewId, ViewerContext};
+
+/// First element is the primary component, all others are optional.
+///
+/// TODO(andreas/clement): More formal definition of an archetype.
+pub type ArchetypeDefinition = vec1::Vec1<ComponentName>;
+
+re_string_interner::declare_new_type!(
+    /// The unique name of a space view type.
+    #[derive(serde::Deserialize, serde::Serialize)]
+    pub struct SpaceViewClassName;
+);
+
+/// Defines a class of space view without any concrete types making it suitable for storage and interfacing.
+///
+/// Implemented by [`crate::SpaceViewClass`].
+///
+/// Each Space View in the viewer's viewport has a single class assigned immutable at its creation time.
+/// The class defines all aspects of its behavior.
+/// It determines which entities are queried, how they are rendered, and how the user can interact with them.
+pub trait DynSpaceViewClass {
+    /// Name of this space view class.
+    ///
+    /// Used for both ui display and identification.
+    /// Must be unique within a viewer session.
+    fn name(&self) -> SpaceViewClassName;
+
+    /// Icon used to identify this space view class.
+    fn icon(&self) -> &'static re_ui::Icon;
+
+    /// Help text describing how to interact with this space view in the ui.
+    fn help_text(&self, re_ui: &re_ui::ReUi, state: &dyn SpaceViewState) -> egui::WidgetText;
+
+    /// Called once for every new space view instance of this class.
+    ///
+    /// The state is *not* persisted across viewer sessions, only shared frame-to-frame.
+    fn new_state(&self) -> Box<dyn SpaceViewState>;
+
+    /// Returns a new scene for this space view class.
+    ///
+    /// Called both to determine the supported archetypes and
+    /// to populate a scene every frame.
+    fn new_scene(&self) -> Box<dyn Scene>;
+
+    /// Optional archetype of the Space View's blueprint properties.
+    ///
+    /// Blueprint components that only apply to the space view itself, not to the entities it displays.
+    fn blueprint_archetype(&self) -> Option<ArchetypeDefinition>;
+
+    /// Preferred aspect ratio for the ui tiles of this space view.
+    fn preferred_tile_aspect_ratio(&self, state: &dyn SpaceViewState) -> Option<f32>;
+
+    /// Executed before the scene is populated, can be use for heuristic & state updates before populating the scene.
+    ///
+    /// Is only allowed to access archetypes defined by [`Self::blueprint_archetype`]
+    /// Passed entity properties are individual properties without propagated values.
+    fn prepare_populate(
+        &self,
+        ctx: &mut ViewerContext<'_>,
+        state: &mut dyn SpaceViewState,
+        entity_paths: &IntSet<EntityPath>,
+        entity_properties: &mut EntityPropertyMap,
+    );
+
+    /// Ui shown when the user selects a space view of this class.
+    ///
+    /// TODO(andreas): Should this be instead implemented via a registered `data_ui` of all blueprint relevant types?
+    fn selection_ui(
+        &self,
+        ctx: &mut ViewerContext<'_>,
+        ui: &mut egui::Ui,
+        state: &mut dyn SpaceViewState,
+        space_origin: &EntityPath,
+        space_view_id: SpaceViewId,
+    );
+
+    /// Draws the ui for this space view type and handles ui events.
+    ///
+    /// The scene passed in was previously created by [`Self::new_scene`] and got populated by the time it is passed.
+    /// The state passed in was previously created by [`Self::new_state`] and is kept frame-to-frame.
+    fn ui(
+        &self,
+        ctx: &mut ViewerContext<'_>,
+        ui: &mut egui::Ui,
+        state: &mut dyn SpaceViewState,
+        scene: Box<dyn Scene>,
+        space_origin: &EntityPath,
+        space_view_id: SpaceViewId,
+    );
+}
+
+/// Unserialized frame to frame state of a space view.
+///
+/// For any state that should be persisted, use the Blueprint!
+/// This state is used for transient state, such as animation or uncommitted ui state like dragging a camera.
+/// (on mouse release, the camera would be committed to the blueprint).
+pub trait SpaceViewState: std::any::Any {
+    /// Converts itself to a reference of [`std::any::Any`], which enables downcasting to concrete types.
+    fn as_any(&self) -> &dyn std::any::Any;
+
+    /// Converts itself to a reference of [`std::any::Any`], which enables downcasting to concrete types.
+    fn as_any_mut(&mut self) -> &mut dyn std::any::Any;
+}

crates/re_viewer_context/src/space_view/mod.rs

@@ -4,22 +4,22 @@
 //! Does not implement any concrete space view.
 
 // TODO(andreas): Can we move some of these to the `re_space_view` crate?
+mod dyn_space_view_class;
 mod highlights;
 mod scene;
 mod scene_context;
 mod scene_part;
 mod scene_query;
 mod space_view_class;
-mod space_view_class_impl;
 mod space_view_class_registry;
 
+pub use dyn_space_view_class::{
+    ArchetypeDefinition, DynSpaceViewClass, SpaceViewClassName, SpaceViewState,
+};
 pub use highlights::{SpaceViewEntityHighlight, SpaceViewHighlights, SpaceViewOutlineMasks};
 pub use scene::{Scene, TypedScene};
 pub use scene_context::{SceneContext, SceneContextPart};
 pub use scene_part::{ScenePart, ScenePartCollection};
 pub use scene_query::SceneQuery;
-pub use space_view_class::{
-    ArchetypeDefinition, SpaceViewClass, SpaceViewClassName, SpaceViewState,
-};
-pub use space_view_class_impl::SpaceViewClassImpl;
+pub use space_view_class::SpaceViewClass;
 pub use space_view_class_registry::{SpaceViewClassRegistry, SpaceViewClassRegistryError};