ability to add/remove interaction modes dynamically

editor/src/interaction/mod.rs

@@ -5,6 +5,7 @@ use crate::{
             color::Color,
             pool::Handle,
             uuid::Uuid,
+            TypeUuidProvider,
         },
         gui::{
             border::BorderBuilder,
@@ -22,9 +23,10 @@ use crate::{
         scene::{camera::Projection, graph::Graph, node::Node},
     },
     load_image,
+    message::MessageSender,
     scene::{controller::SceneController, Selection},
     settings::Settings,
-    Engine,
+    Engine, Message,
 };
 use std::any::Any;
 
@@ -41,6 +43,8 @@ pub trait BaseInteractionMode: 'static {
     fn as_any(&self) -> &dyn Any;
 
     fn as_any_mut(&mut self) -> &mut dyn Any;
+
+    fn into_any(self: Box<Self>) -> Box<dyn Any>;
 }
 
 impl<T> BaseInteractionMode for T
@@ -54,6 +58,10 @@ where
     fn as_any_mut(&mut self) -> &mut dyn Any {
         self
     }
+
+    fn into_any(self: Box<Self>) -> Box<dyn Any> {
+        self
+    }
 }
 
 pub trait InteractionMode: BaseInteractionMode {
@@ -228,11 +236,33 @@ pub struct InteractionModeContainer {
     // is not an issue, because there are tiny amount of modes anyway (currently - max 5) and linear
     // search is faster in such conditions.
     container: Vec<Box<dyn InteractionMode>>,
+    pub sender: Option<MessageSender>,
 }
 
 impl InteractionModeContainer {
+    fn try_notify_changed(&self) {
+        if let Some(sender) = self.sender.as_ref() {
+            sender.send(Message::SyncInteractionModes);
+        }
+    }
+
     pub fn add<T: InteractionMode>(&mut self, mode: T) {
         self.container.push(Box::new(mode));
+        self.try_notify_changed();
+    }
+
+    pub fn remove(&mut self, id: &Uuid) -> Option<Box<dyn InteractionMode>> {
+        if let Some(position) = self.container.iter().position(|mode| mode.uuid() == *id) {
+            self.try_notify_changed();
+            Some(self.container.remove(position))
+        } else {
+            None
+        }
+    }
+
+    pub fn remove_typed<T: InteractionMode + TypeUuidProvider>(&mut self) -> Option<Box<T>> {
+        self.remove(&T::type_uuid())
+            .and_then(|mode| mode.into_any().downcast::<T>().ok())
     }
 
     pub fn iter_mut(&mut self) -> impl Iterator<Item = &mut dyn InteractionMode> + '_ {
@@ -254,6 +284,7 @@ impl InteractionModeContainer {
     }
 
     pub fn drain(&mut self) -> impl Iterator<Item = Box<dyn InteractionMode>> + '_ {
+        self.try_notify_changed();
         self.container.drain(..)
     }
 }

editor/src/lib.rs

@@ -2488,6 +2488,12 @@ impl Editor {
                         viewer.open(data, &mut self.engine);
                         self.surface_data_viewer = Some(viewer);
                     }
+                    Message::SyncInteractionModes => {
+                        self.scene_viewer.sync_interaction_modes(
+                            self.scenes.current_scene_entry_mut(),
+                            self.engine.user_interfaces.first_mut(),
+                        );
+                    }
                     _ => (),
                 }
             }

editor/src/message.rs

@@ -78,6 +78,7 @@ pub enum Message {
     SaveLayout,
     LoadLayout,
     ViewSurfaceData(SurfaceResource),
+    SyncInteractionModes,
 }
 
 #[derive(Clone, Debug)]

editor/src/scene/container.rs

@@ -93,6 +93,7 @@ impl EditorSceneEntry {
             message_sender.clone(),
             scene_viewer.frame(),
         ));
+        interaction_modes.sender = Some(message_sender.clone());
 
         let mut entry = EditorSceneEntry {
             has_unsaved_changes: false,
@@ -128,6 +129,7 @@ impl EditorSceneEntry {
             message_sender.clone(),
         ));
         interaction_modes.add(MoveWidgetsInteractionMode::new(message_sender.clone()));
+        interaction_modes.sender = Some(message_sender.clone());
 
         let mut entry = EditorSceneEntry {
             has_unsaved_changes: false,

editor/src/scene_viewer/mod.rs

@@ -592,9 +592,9 @@ impl SceneViewer {
         }
     }
 
-    pub fn on_current_scene_changed(
+    pub fn sync_interaction_modes(
         &mut self,
-        new_scene: Option<&mut EditorSceneEntry>,
+        scene: Option<&mut EditorSceneEntry>,
         ui: &mut UserInterface,
     ) {
         // Remove interaction mode buttons first.
@@ -603,7 +603,7 @@ impl SceneViewer {
         }
 
         // Create new buttons for each mode.
-        if let Some(scene_entry) = new_scene {
+        if let Some(scene_entry) = scene {
             for mode in scene_entry.interaction_modes.iter_mut() {
                 let button = mode.make_button(
                     &mut ui.build_ctx(),
@@ -619,6 +619,14 @@ impl SceneViewer {
         }
     }
 
+    pub fn on_current_scene_changed(
+        &mut self,
+        new_scene: Option<&mut EditorSceneEntry>,
+        ui: &mut UserInterface,
+    ) {
+        self.sync_interaction_modes(new_scene, ui)
+    }
+
     pub fn handle_ui_message(
         &mut self,
         message: &mut UiMessage,