Wrap `NavmesherBoard` inside new `Router` struct

topola-egui/src/display.rs

@@ -34,7 +34,7 @@ impl Display {
         viewport: &Viewport,
         workspace: &Workspace,
     ) {
-        let board = workspace.autorouter.navmesher_board().board();
+        let board = workspace.autorouter.router().navmesher_board().board();
         let layout = board.layout();
 
         // Start from the bottom layer so that top layers are drawn on top.
@@ -166,7 +166,7 @@ impl Display {
         viewport: &Viewport,
         workspace: &Workspace,
     ) {
-        let board = workspace.autorouter.navmesher_board().board();
+        let board = workspace.autorouter.router().navmesher_board().board();
         let layout = board.layout();
 
         for layer in (0..*layout.layer_count()).rev() {
@@ -235,6 +235,7 @@ impl Display {
     ) {
         for layer in 0..*workspace
             .autorouter
+            .router()
             .navmesher_board()
             .board()
             .layout()
@@ -243,6 +244,7 @@ impl Display {
             if workspace.appearance_panel.visible[layer] {
                 for navmesh in workspace
                     .autorouter
+                    .router()
                     .navmesher_board()
                     .navmesher()
                     .layer_navmeshers()[layer]

topola-egui/src/viewport.rs

@@ -55,6 +55,7 @@ impl Viewport {
                         if response.clicked() {
                             if let Some(pin_selector) = workspace
                                 .autorouter
+                                .router()
                                 .navmesher_board()
                                 .board()
                                 .point_pin_selector(
@@ -118,6 +119,7 @@ impl Viewport {
     fn boundary_bounding_box(workspace: &Workspace) -> egui::Rect {
         let first = workspace
             .autorouter
+            .router()
             .navmesher_board()
             .board()
             .layout()
@@ -130,6 +132,7 @@ impl Viewport {
 
         for point in workspace
             .autorouter
+            .router()
             .navmesher_board()
             .board()
             .layout()

topola-egui/src/workspace.rs

@@ -25,6 +25,6 @@ impl Workspace {
 
     pub fn update_appearance_panel(&mut self, ctx: &egui::Context) {
         self.appearance_panel
-            .update(ctx, &self.autorouter.navmesher_board().board());
+            .update(ctx, &self.autorouter.router().navmesher_board().board());
     }
 }

topola/src/autorouter.rs

@@ -4,12 +4,12 @@
 
 use derive_getters::Getters;
 
-use crate::{Board, Ratsnest, navmesher::NavmesherBoard};
+use crate::{Board, Ratsnest, router::Router};
 
 #[derive(Clone, Debug, Getters)]
 pub struct Autorouter {
-    navmesher_board: NavmesherBoard,
     ratsnest: Ratsnest,
+    router: Router,
 }
 
 impl Autorouter {
@@ -17,7 +17,7 @@ impl Autorouter {
         let ratsnest = Ratsnest::new(&board);
 
         Self {
-            navmesher_board: NavmesherBoard::new(board),
+            router: Router::new(board),
             ratsnest,
         }
     }

topola/src/connectivity.rs

@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2026 Topola contributors
+//
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+use polygon_unionfind::UnionFind;
+
+use crate::Board;
+
+pub struct Connectivity {
+    joints_unionfind: UnionFind,
+    segments_unionfind: UnionFind,
+    polygons_unionfind: UnionFind,
+}
+
+impl Connectivity {
+    pub fn new(board: &Board) -> Self {
+        let mut this = Connectivity {
+            joints_unionfind: UnionFind::with_len(
+                board.layout().joints().collection().num_elements(),
+            ),
+            segments_unionfind: UnionFind::with_len(
+                board.layout().segments().collection().num_elements(),
+            ),
+            polygons_unionfind: UnionFind::with_len(
+                board.layout().polygons().collection().num_elements(),
+            ),
+        };
+
+        TODO
+    }
+}

topola/src/drawer.rs

@@ -0,0 +1,18 @@
+// SPDX-FileCopyrightText: 2026 Topola contributors
+//
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+use derive_getters::Getters;
+
+use crate::navmesher::NavmesherBoard;
+
+#[derive(Clone, Debug, Getters)]
+pub struct Drawer {
+    navmesher_board: NavmesherBoard,
+}
+
+impl Drawer {
+    pub fn new(navmesher_board: NavmesherBoard) -> Self {
+        Self { navmesher_board }
+    }
+}

topola/src/lib.rs

@@ -4,11 +4,14 @@
 
 mod autorouter;
 mod board;
+mod drawer;
 mod layout;
 mod math;
 mod navmesher;
+mod pathfinder;
 mod primitives;
 mod ratsnest;
+mod router;
 mod selection;
 mod specctra;
 

topola/src/pathfinder.rs

@@ -0,0 +1,18 @@
+// SPDX-FileCopyrightText: 2026 Topola contributors
+//
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+use derive_getters::Getters;
+
+use crate::navmesher::NavmesherBoard;
+
+#[derive(Clone, Debug, Getters)]
+pub struct Pathfinder {
+    navmesher_board: NavmesherBoard,
+}
+
+impl Pathfinder {
+    pub fn new(navmesher_board: NavmesherBoard) -> Self {
+        Self { navmesher_board }
+    }
+}

topola/src/router.rs

@@ -0,0 +1,26 @@
+// SPDX-FileCopyrightText: 2026 Topola contributors
+//
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+use crate::{Board, drawer::Drawer, navmesher::NavmesherBoard, pathfinder::Pathfinder};
+
+#[derive(Clone, Debug)]
+pub enum Router {
+    Resting(NavmesherBoard),
+    Pathfinder(Pathfinder),
+    Drawer(Drawer),
+}
+
+impl Router {
+    pub fn new(board: Board) -> Self {
+        Self::Resting(NavmesherBoard::new(board))
+    }
+
+    pub fn navmesher_board(&self) -> &NavmesherBoard {
+        match self {
+            Router::Resting(navmesher_board) => navmesher_board,
+            Router::Pathfinder(pathfinder) => pathfinder.navmesher_board(),
+            Router::Drawer(drawer) => drawer.navmesher_board(),
+        }
+    }
+}