add: loading

README.md

@@ -49,7 +49,8 @@ la-fabrik/
 └── src/
     ├── world/                              # Persistent 3D world composition
     │   ├── World.tsx                       # Active scene composition
-    │   ├── GameMap.tsx                     # Map loading and octree collision
+    │   ├── GameMap.tsx                     # Map loading and progressive rendering
+    │   ├── GameMapCollision.tsx            # Collision-only octree source
     │   ├── Lighting.tsx                    # Ambient, directional, point lights
     │   ├── Environment.tsx                 # Scene background / sky model
     │   ├── GameMusic.tsx                   # Game scene music lifecycle

docs/technical/architecture.md

@@ -14,7 +14,9 @@ This document describes the code that exists today in the repository.
   - debug helpers and debug camera mode
   - either the map scene or the debug physics test scene
   - the player rig when the active camera mode is `player`
-- `src/world/GameMap.tsx` loads map nodes from `public/map.json`, resolves available models, and builds the collision octree.
+- `src/hooks/world/useWorldSceneLoading.ts` owns the production scene loading state shared by `World`, `GameMap`, and the player octree readiness.
+- `src/world/GameMap.tsx` loads map nodes from `public/map.json`, resolves available models, renders them progressively, and shows fallback cubes for missing models.
+- `src/world/GameMapCollision.tsx` builds the player collision octree from dedicated collision nodes only.
 - `src/world/GameStageContent.tsx` is wrapped in Rapier `Physics` in the production game scene so stage gameplay objects can use physics without moving the map or player to Rapier. It now mounts reusable `RepairGame` instances for `bike`, `pylone`, and `ferme` mission states.
 - `src/world/debug/TestMap.tsx` provides a debug-oriented interaction and physics map with the existing grab/trigger/model-preview objects plus separate `Bike`, `Pylone`, and `Farm` repair playground zones.
 - `src/world/player/Player.tsx` mounts the camera and controller.
@@ -24,7 +26,8 @@ This document describes the code that exists today in the repository.
 
 The project currently uses two collision layers with separate responsibilities:
 
-- `GameMap` builds an octree used by the player controller for map collision.
+- `GameMapCollision` builds an octree used by the player controller for map collision.
+- The player octree must be built from a small collision-only subset of map nodes. It currently uses the `terrain` node only instead of traversing the full visible map, because building an octree from all rendered props can overload the browser renderer.
 - `GameStageContent` is wrapped in Rapier `Physics` for gameplay objects such as repair triggers, cases, grabbables, and future mission-specific objects.
 - `TestMap` owns its own Rapier `Physics` playground so repair gameplay can be tuned per mission state without depending on the production map layout.
 
@@ -53,6 +56,7 @@ Keep the player and map octree outside the Rapier provider until there is a deli
 - `src/components/ui/debug/DebugOverlayLayout.tsx` mounts the compact HTML debug overlay when enabled from `lil-gui`.
 - `src/components/ui/debug/GameStateDebugPanel.tsx` exposes current game state, main/sub-state switching, previous/next step controls, and reset.
 - `src/components/ui/debug/HandTrackingDebugPanel.tsx` shows hand tracking status, usage, loaded glove model, hand count, and fist state while hand tracking is active.
+- `src/components/ui/SceneLoadingOverlay.tsx` displays the fullscreen loading state for 3D scenes, including the production game scene, debug physics scene, and editor scene.
 - `src/components/three/handTracking/HandTrackingGlove.tsx` places the rigged `gant_l` and `gant_r` models on detected hands in the debug physics scene.
 - `src/components/debug/scene/DebugHelpers.tsx` mounts debug helpers.
 - `src/components/debug/scene/DebugCameraControls.tsx` mounts the free debug camera.
@@ -85,7 +89,8 @@ Keep the player and map octree outside the Rapier provider until there is a deli
 - `public/map.json` is expected to be a `MapNode[]`.
 - Each map node `name` maps to `public/models/{name}/model.glb` when available, with `public/models/{name}/model.gltf` kept as fallback.
 - The editor renders a fallback cube for missing models.
-- The game scene filters out nodes whose model cannot be resolved.
+- The game scene renders fallback cubes for nodes whose model cannot be resolved.
+- The game scene currently uses `terrain` as the collision source for the player octree. Additional collision nodes should be explicit lightweight collision assets, not arbitrary visible decoration models.
 
 ## Current Limitations
 

docs/user/features.md

@@ -6,6 +6,7 @@ This document lists features that are implemented in the current codebase.
 
 - Fullscreen React Three Fiber scene
 - Main map scene loaded from `public/map.json` and matching `public/models/{name}/model.glb` or `model.gltf` assets
+- Minimal fullscreen scene loading overlay for 3D scenes, with a global progress bar used by the production map, debug physics scene, and editor scene
 - Debug physics test scene selectable from the debug panel, including grab/trigger tests, an animated model preview, and separate repair playground zones for `bike`, `pylone`, and `ferme`
 - Rapier physics context available for production stage gameplay objects
 - Ambient and directional lighting
@@ -17,7 +18,7 @@ This document lists features that are implemented in the current codebase.
 - Pointer lock mouse look
 - Movement with `ZQSD`
 - Jumping
-- Octree-based collision against the loaded map
+- Octree-based collision against dedicated map collision nodes, currently scoped to `terrain`
 
 ## Interactions
 
@@ -68,7 +69,6 @@ This document lists features that are implemented in the current codebase.
 - zone system
 - cinematic system
 - dialogue system
-- loading flow
 - minimap and mission HUD
 - full production separation between gameplay and debug scenes
 - production backend persistence for editor saves

src/components/three/interaction/GrabbableObject.tsx

@@ -66,7 +66,6 @@ const _snapTargetWorldPosition = new THREE.Vector3();
 const _handRaycaster = new THREE.Raycaster();
 
 const HAND_GRAB_SCREEN_RADIUS = 0.04;
-const HAND_DEPTH_SENSITIVITY = 4;
 const HAND_HIT_OFFSETS: Array<[number, number]> = [
   [0, 0],
   [HAND_GRAB_SCREEN_RADIUS, 0],
@@ -144,8 +143,6 @@ export function GrabbableObject({
   const rbRef = useRef<RapierRigidBody>(null);
   const isHolding = useRef(false);
   const isHandHolding = useRef(false);
-  const handHoldDistance = useRef<number | null>(null);
-  const handHoldStartZ = useRef<number | null>(null);
   const snapTween = useRef<gsap.core.Tween | null>(null);
 
   useEffect(() => {
@@ -270,8 +267,6 @@ export function GrabbableObject({
           : null;
 
         isHandHolding.current = Boolean(hit);
-        handHoldDistance.current = hit ? GRAB_HOLD_DISTANCE_DEFAULT : null;
-        handHoldStartZ.current = hit ? fistHand.z : null;
         InteractionManager.getInstance().setHandHolding(isHandHolding.current);
       }
     } else {
@@ -279,28 +274,15 @@ export function GrabbableObject({
         snapToNearestTarget();
       }
       isHandHolding.current = false;
-      handHoldDistance.current = null;
-      handHoldStartZ.current = null;
       InteractionManager.getInstance().setHandHolding(false);
     }
 
     if (!isHolding.current && !isHandHolding.current) return;
 
     if (fistHand && isHandHolding.current) {
-      const depthOffset =
-        handHoldStartZ.current === null
-          ? 0
-          : (fistHand.z - handHoldStartZ.current) * HAND_DEPTH_SENSITIVITY;
-      const holdDistance = THREE.MathUtils.clamp(
-        (handHoldDistance.current ?? grabDebugParams.holdDistance) +
-          depthOffset,
-        GRAB_HOLD_DISTANCE_MIN,
-        GRAB_HOLD_DISTANCE_MAX,
-      );
-
       _holdTarget
         .copy(_cameraPos)
-        .addScaledVector(_handDirection, holdDistance);
+        .addScaledVector(_handDirection, grabDebugParams.holdDistance);
     } else {
       camera.getWorldDirection(_holdTarget);
       _holdTarget

src/components/ui/SceneLoadingOverlay.tsx

@@ -0,0 +1,27 @@
+import type { SceneLoadingState } from "@/types/world/sceneLoading";
+
+interface SceneLoadingOverlayProps {
+  state: SceneLoadingState;
+}
+
+export function SceneLoadingOverlay({
+  state,
+}: SceneLoadingOverlayProps): React.JSX.Element | null {
+  const isReady = state.status === "ready";
+  const progress = Math.round(Math.max(0, Math.min(1, state.progress)) * 100);
+
+  return (
+    <div
+      className={`scene-loading-overlay${isReady ? " scene-loading-overlay--ready" : ""}`}
+      aria-live="polite"
+    >
+      <div className="scene-loading-overlay__content">
+        <strong>{state.currentStep}</strong>
+        <div className="scene-loading-overlay__track">
+          <span style={{ width: `${progress}%` }} />
+          <em>{progress}%</em>
+        </div>
+      </div>
+    </div>
+  );
+}

src/hooks/three/useOctreeGraphNode.ts

@@ -8,6 +8,7 @@ export function useOctreeGraphNode(
   graphNodeRef: RefObject<Object3D | null>,
   onOctreeReady: OctreeReadyHandler,
   rebuildKey: string | number = 0,
+  enabled = true,
 ): void {
   const octreeBuilt = useRef(false);
 
@@ -17,7 +18,7 @@ export function useOctreeGraphNode(
 
   useEffect(() => {
     const graphNode = graphNodeRef.current;
-    if (octreeBuilt.current || !graphNode) return;
+    if (!enabled || octreeBuilt.current || !graphNode) return;
     octreeBuilt.current = true;
 
     graphNode.updateMatrixWorld(true);
@@ -25,5 +26,5 @@ export function useOctreeGraphNode(
     const octree = new Octree();
     octree.fromGraphNode(graphNode);
     onOctreeReady(octree);
-  }, [graphNodeRef, onOctreeReady, rebuildKey]);
+  }, [enabled, graphNodeRef, onOctreeReady, rebuildKey]);
 }

src/hooks/world/useWorldSceneLoading.ts

@@ -0,0 +1,81 @@
+import { useCallback, useEffect, useState } from "react";
+import type { Octree } from "three/addons/math/Octree.js";
+import type { SceneMode } from "@/types/debug/debug";
+import type { SceneLoadingChangeHandler } from "@/types/world/sceneLoading";
+
+interface UseWorldSceneLoadingOptions {
+  onLoadingStateChange?: SceneLoadingChangeHandler | undefined;
+  sceneMode: SceneMode;
+}
+
+interface UseWorldSceneLoadingResult {
+  octree: Octree | null;
+  showGameStage: boolean;
+  handleGameMapLoaded: () => void;
+  handleOctreeReady: (octree: Octree) => void;
+}
+
+export function useWorldSceneLoading({
+  onLoadingStateChange,
+  sceneMode,
+}: UseWorldSceneLoadingOptions): UseWorldSceneLoadingResult {
+  const [octree, setOctree] = useState<Octree | null>(null);
+  const [gameMapLoaded, setGameMapLoaded] = useState(false);
+  const showGameStage = sceneMode === "game" && gameMapLoaded;
+  const sceneReady =
+    (sceneMode === "game" && gameMapLoaded) ||
+    (sceneMode === "physics" && octree !== null);
+
+  const handleGameMapLoaded = useCallback(() => {
+    setGameMapLoaded(true);
+  }, []);
+
+  const handleOctreeReady = useCallback(
+    (nextOctree: Octree) => {
+      setOctree(nextOctree);
+      onLoadingStateChange?.({
+        currentStep: "Collision prête",
+        progress: 0.92,
+        status: "loading",
+      });
+    },
+    [onLoadingStateChange],
+  );
+
+  useEffect(() => {
+    onLoadingStateChange?.({
+      currentStep: "Initialisation du jeu",
+      progress: 0,
+      status: "loading",
+    });
+  }, [onLoadingStateChange, sceneMode]);
+
+  useEffect(() => {
+    if (!sceneReady) return undefined;
+
+    onLoadingStateChange?.({
+      currentStep: "Gameplay prêt",
+      progress: 0.96,
+      status: "loading",
+    });
+
+    const timeoutId = window.setTimeout(() => {
+      onLoadingStateChange?.({
+        currentStep: "Gameplay prêt",
+        progress: 1,
+        status: "ready",
+      });
+    }, 150);
+
+    return () => {
+      window.clearTimeout(timeoutId);
+    };
+  }, [onLoadingStateChange, sceneReady]);
+
+  return {
+    octree,
+    showGameStage,
+    handleGameMapLoaded,
+    handleOctreeReady,
+  };
+}

src/index.css

@@ -397,6 +397,78 @@ canvas {
   letter-spacing: 0.03em;
 }
 
+.scene-loading-overlay {
+  position: fixed;
+  inset: 0;
+  z-index: 30;
+  display: grid;
+  place-items: center;
+  width: 100vw;
+  height: 100vh;
+  background: #ffffff;
+  pointer-events: none;
+  opacity: 1;
+  transition: opacity 640ms ease;
+}
+
+.scene-loading-overlay--ready {
+  opacity: 0;
+}
+
+.scene-loading-overlay__content {
+  display: grid;
+  justify-items: center;
+  gap: 18px;
+  width: min(360px, calc(100vw - 48px));
+  padding: 28px;
+  background: rgba(255, 255, 255, 0.92);
+  border: 1px solid rgba(15, 23, 42, 0.08);
+  border-radius: 28px;
+  box-shadow: 0 24px 80px rgba(15, 23, 42, 0.12);
+}
+
+.scene-loading-overlay strong {
+  color: #1e293b;
+  font-size: 15px;
+  font-weight: 600;
+  letter-spacing: 0.02em;
+  line-height: 1.45;
+  text-align: center;
+  text-transform: uppercase;
+}
+
+.scene-loading-overlay__track {
+  position: relative;
+  overflow: hidden;
+  width: 100%;
+  height: 18px;
+  background: #e2e8f0;
+  border-radius: 999px;
+  box-shadow: inset 0 0 0 1px rgba(15, 23, 42, 0.04);
+}
+
+.scene-loading-overlay__track span {
+  display: block;
+  height: 100%;
+  background: linear-gradient(90deg, #2563eb, #38bdf8);
+  border-radius: inherit;
+  transition: width 180ms ease;
+}
+
+.scene-loading-overlay__track em {
+  position: absolute;
+  inset: 0;
+  display: grid;
+  place-items: center;
+  color: #ffffff;
+  font-size: 11px;
+  font-style: normal;
+  font-weight: 700;
+  letter-spacing: 0.04em;
+  line-height: 1;
+  text-shadow: 0 1px 4px rgba(15, 23, 42, 0.35);
+}
+
 /* Debug overlay panels */
 .debug-overlay-layout {
   position: fixed;

src/pages/editor/page.tsx

@@ -1,17 +1,53 @@
-import { useCallback, useState } from "react";
+import { Suspense, useCallback, useEffect, useState } from "react";
 import { Canvas } from "@react-three/fiber";
+import { useProgress } from "@react-three/drei";
 import { EditorControls } from "@/components/editor/EditorControls";
 import { EditorScene } from "@/components/editor/scene/EditorScene";
+import { SceneLoadingOverlay } from "@/components/ui/SceneLoadingOverlay";
 import { useEditorHistory } from "@/hooks/editor/useEditorHistory";
 import { useEditorSceneData } from "@/hooks/editor/useEditorSceneData";
 import type { MapNode, SceneData, TransformMode } from "@/types/editor/editor";
+import {
+  INITIAL_SCENE_LOADING_STATE,
+  type SceneLoadingChangeHandler,
+  type SceneLoadingState,
+} from "@/types/world/sceneLoading";
 
 const SAVE_ERROR_MESSAGE = "Erreur lors de l'enregistrement";
 
+interface EditorSceneLoadingTrackerProps {
+  onLoadingStateChange: SceneLoadingChangeHandler;
+}
+
 function serializeMapNodes(sceneData: SceneData): string {
   return JSON.stringify(sceneData.mapNodes, null, 2);
 }
 
+function EditorSceneLoadingTracker({
+  onLoadingStateChange,
+}: EditorSceneLoadingTrackerProps): null {
+  const { active, progress } = useProgress();
+
+  useEffect(() => {
+    if (active) {
+      onLoadingStateChange({
+        currentStep: "Importation des models",
+        progress: 0.2 + (progress / 100) * 0.7,
+        status: "loading",
+      });
+      return;
+    }
+
+    onLoadingStateChange({
+      currentStep: "Gameplay prêt",
+      progress: 1,
+      status: "ready",
+    });
+  }, [active, onLoadingStateChange, progress]);
+
+  return null;
+}
+
 export function EditorPage(): React.JSX.Element {
   const {
     hasMapJson,
@@ -28,6 +64,35 @@ export function EditorPage(): React.JSX.Element {
   const [transformMode, setTransformMode] =
     useState<TransformMode>("translate");
   const [isPlayerMode, setIsPlayerMode] = useState(false);
+  const [sceneLoadingState, setSceneLoadingState] = useState<SceneLoadingState>(
+    {
+      ...INITIAL_SCENE_LOADING_STATE,
+      currentStep: "Montage progressif des models",
+      progress: 0.2,
+    },
+  );
+  const handleSceneLoadingStateChange = useCallback(
+    (nextState: SceneLoadingState) => {
+      setSceneLoadingState((currentState) => {
+        const shouldRestartProgress = currentState.status === "ready";
+
+        return {
+          ...nextState,
+          progress: shouldRestartProgress
+            ? nextState.progress
+            : Math.max(currentState.progress, nextState.progress),
+        };
+      });
+    },
+    [],
+  );
+  const editorLoadingState = isMapLoading
+    ? {
+        currentStep: "Récupération blocking",
+        progress: 0.08,
+        status: "loading" as const,
+      }
+    : sceneLoadingState;
 
   const {
     undoCount,
@@ -103,10 +168,7 @@ export function EditorPage(): React.JSX.Element {
   if (isMapLoading) {
     return (
       <div className="editor-container">
-        <div className="editor-loading">
+        <SceneLoadingOverlay state={editorLoadingState} />
-          <h2>Chargement de l'éditeur...</h2>
-          <p>Vérification de map.json dans public/</p>
-        </div>
       </div>
     );
   }
@@ -157,6 +219,10 @@ export function EditorPage(): React.JSX.Element {
           gl.setClearColor("#050505");
         }}
       >
+        <EditorSceneLoadingTracker
+          onLoadingStateChange={handleSceneLoadingStateChange}
+        />
+        <Suspense fallback={null}>
           <EditorScene
             sceneData={sceneData!}
             selectedNodeIndex={selectedNodeIndex}
@@ -172,8 +238,11 @@ export function EditorPage(): React.JSX.Element {
             onRedo={handleRedo}
             isPlayerMode={isPlayerMode}
           />
+        </Suspense>
       </Canvas>
 
+      <SceneLoadingOverlay state={editorLoadingState} />
+
       {sceneData && (
         <EditorControls
           transformMode={transformMode}

src/pages/page.tsx

@@ -1,12 +1,36 @@
-import { Suspense } from "react";
+import { Suspense, useCallback, useState } from "react";
 import { Canvas } from "@react-three/fiber";
 import * as THREE from "three";
 import { DebugPerf } from "@/components/debug/DebugPerf";
 import { GameUI } from "@/components/ui/GameUI";
+import { SceneLoadingOverlay } from "@/components/ui/SceneLoadingOverlay";
 import { HandTrackingProvider } from "@/providers/gameplay/HandTrackingProvider";
+import {
+  INITIAL_SCENE_LOADING_STATE,
+  type SceneLoadingState,
+} from "@/types/world/sceneLoading";
 import { World } from "@/world/World";
 
 export function HomePage(): React.JSX.Element {
+  const [sceneLoadingState, setSceneLoadingState] = useState<SceneLoadingState>(
+    INITIAL_SCENE_LOADING_STATE,
+  );
+  const handleSceneLoadingStateChange = useCallback(
+    (nextState: SceneLoadingState) => {
+      setSceneLoadingState((currentState) => {
+        const shouldRestartProgress = currentState.status === "ready";
+
+        return {
+          ...nextState,
+          progress: shouldRestartProgress
+            ? nextState.progress
+            : Math.max(currentState.progress, nextState.progress),
+        };
+      });
+    },
+    [],
+  );
+
   return (
     <HandTrackingProvider>
       <Canvas
@@ -14,11 +38,12 @@ export function HomePage(): React.JSX.Element {
         shadows={{ type: THREE.PCFShadowMap }}
       >
         <Suspense fallback={null}>
-          <World />
+          <World onLoadingStateChange={handleSceneLoadingStateChange} />
           <DebugPerf />
         </Suspense>
       </Canvas>
       <GameUI />
+      <SceneLoadingOverlay state={sceneLoadingState} />
     </HandTrackingProvider>
   );
 }

src/types/world/sceneLoading.ts

@@ -0,0 +1,15 @@
+export type SceneLoadingStatus = "loading" | "ready";
+
+export interface SceneLoadingState {
+  currentStep: string;
+  progress: number;
+  status: SceneLoadingStatus;
+}
+
+export type SceneLoadingChangeHandler = (state: SceneLoadingState) => void;
+
+export const INITIAL_SCENE_LOADING_STATE: SceneLoadingState = {
+  currentStep: "Initialisation du jeu",
+  progress: 0,
+  status: "loading",
+};

src/world/GameMap.tsx

@@ -1,9 +1,9 @@
 import type { ReactNode } from "react";
-import { Component, useEffect, useRef, useState } from "react";
+import { Component, Suspense, useEffect, useState } from "react";
-import * as THREE from "three";
 import { useClonedObject } from "@/hooks/three/useClonedObject";
 import { useLoggedGLTF } from "@/hooks/three/useLoggedGLTF";
-import { useOctreeGraphNode } from "@/hooks/three/useOctreeGraphNode";
+import { GameMapCollision } from "@/world/GameMapCollision";
+import type { SceneLoadingChangeHandler } from "@/types/world/sceneLoading";
 import { logger } from "@/utils/core/Logger";
 import { loadMapSceneData } from "@/utils/map/loadMapSceneData";
 import { logModelLoadError } from "@/utils/three/modelLoadLogger";
@@ -12,12 +12,13 @@ import type { OctreeReadyHandler } from "@/types/three/three";
 
 interface LoadedMapNode {
   node: MapNode;
-  modelUrl: string;
+  modelUrl: string | null;
 }
 
 interface ErrorBoundaryProps {
   children: ReactNode;
-  modelUrl: string;
+  fallback: ReactNode;
+  modelUrl: string | null;
   node: MapNode;
 }
 
@@ -41,7 +42,7 @@ class ModelErrorBoundary extends Component<
   componentDidCatch(error: Error): void {
     logModelLoadError(
       {
-        modelPath: this.props.modelUrl,
+        modelPath: this.props.modelUrl ?? `missing:${this.props.node.name}`,
         scope: "GameMap.ModelInstance",
         position: this.props.node.position,
         rotation: this.props.node.rotation,
@@ -53,7 +54,7 @@ class ModelErrorBoundary extends Component<
 
   render(): ReactNode {
     if (this.state.hasError) {
-      return null;
+      return this.props.fallback;
     }
 
     return this.props.children;
@@ -61,35 +62,62 @@ class ModelErrorBoundary extends Component<
 }
 
 interface GameMapProps {
+  onLoaded?: (() => void) | undefined;
+  onLoadingStateChange?: SceneLoadingChangeHandler | undefined;
   onOctreeReady: OctreeReadyHandler;
 }
 
-export function GameMap({ onOctreeReady }: GameMapProps): React.JSX.Element {
+const MAP_RENDER_BATCH_SIZE = 12;
-  const [mapNodes, setMapNodes] = useState<LoadedMapNode[]>([]);
-  const groupRef = useRef<THREE.Group>(null);
 
-  useOctreeGraphNode(groupRef, onOctreeReady, mapNodes.length);
+export function GameMap({
+  onLoaded,
+  onLoadingStateChange,
+  onOctreeReady,
+}: GameMapProps): React.JSX.Element {
+  const [mapNodes, setMapNodes] = useState<LoadedMapNode[]>([]);
+  const [mapLoaded, setMapLoaded] = useState(false);
+  const [visibleNodeCount, setVisibleNodeCount] = useState(0);
+  const visibleMapNodes = mapNodes.slice(0, visibleNodeCount);
+  const mapReady = mapLoaded && visibleNodeCount >= mapNodes.length;
 
   useEffect(() => {
+    onLoadingStateChange?.({
+      currentStep: "Récupération blocking",
+      progress: 0.05,
+      status: "loading",
+    });
+
     const loadMap = async () => {
       try {
         const sceneData = await loadMapSceneData();
         if (!sceneData) {
           logger.warn("GameMap", "map.json not found");
+          onLoadingStateChange?.({
+            currentStep: "Map introuvable",
+            progress: 1,
+            status: "loading",
+          });
           return;
         }
 
-        const loadedMapNodes = sceneData.mapNodes.flatMap((node) => {
+        onLoadingStateChange?.({
-          const modelUrl = sceneData.models.get(node.name);
+          currentStep: "Importation des models",
-          return modelUrl ? [{ node, modelUrl }] : [];
+          progress: 0.18,
+          status: "loading",
         });
-        const missingModelCount =
+
-          sceneData.mapNodes.length - loadedMapNodes.length;
+        const loadedMapNodes = sceneData.mapNodes.map((node) => {
+          const modelUrl = sceneData.models.get(node.name);
+          return { node, modelUrl: modelUrl ?? null };
+        });
+        const missingModelCount = loadedMapNodes.filter(
+          (mapNode) => mapNode.modelUrl === null,
+        ).length;
 
         if (missingModelCount > 0) {
           logger.warn(
             "GameMap",
-            "Map nodes skipped because model files are missing",
+            "Map nodes rendered as fallback cubes because model files are missing",
             {
               missingModelCount,
             },
@@ -97,28 +125,85 @@ export function GameMap({ onOctreeReady }: GameMapProps): React.JSX.Element {
         }
 
         setMapNodes(loadedMapNodes);
+        setMapLoaded(true);
+        setVisibleNodeCount(0);
+        onLoadingStateChange?.({
+          currentStep: "Montage progressif des models",
+          progress: 0.25,
+          status: "loading",
+        });
       } catch (error) {
         logger.error("GameMap", "Error loading map", {
           error: error instanceof Error ? error : new Error(String(error)),
         });
+        onLoadingStateChange?.({
+          currentStep: "Erreur de chargement de la map",
+          progress: 1,
+          status: "loading",
+        });
       }
     };
 
     loadMap();
-  }, []);
+  }, [onLoaded, onLoadingStateChange]);
+
+  useEffect(() => {
+    if (mapNodes.length === 0 || visibleNodeCount >= mapNodes.length) return;
+
+    const frameId = window.requestAnimationFrame(() => {
+      setVisibleNodeCount((current) =>
+        Math.min(current + MAP_RENDER_BATCH_SIZE, mapNodes.length),
+      );
+    });
+
+    return () => {
+      window.cancelAnimationFrame(frameId);
+    };
+  }, [mapNodes.length, visibleNodeCount]);
+
+  useEffect(() => {
+    if (mapNodes.length === 0) return;
+
+    const renderProgress =
+      mapNodes.length === 0 ? 1 : visibleNodeCount / mapNodes.length;
+    onLoadingStateChange?.({
+      currentStep: "Montage progressif des models",
+      progress: 0.25 + renderProgress * 0.45,
+      status: "loading",
+    });
+  }, [mapNodes.length, onLoadingStateChange, visibleNodeCount]);
 
   return (
-    <group ref={groupRef}>
+    <>
-      {mapNodes.map((mapNode, index) => (
+      <group>
+        {visibleMapNodes.map((mapNode, index) => (
           <ModelErrorBoundary
             key={index}
+            fallback={<FallbackMapNode node={mapNode.node} />}
             modelUrl={mapNode.modelUrl}
             node={mapNode.node}
           >
-          <ModelInstance node={mapNode.node} modelUrl={mapNode.modelUrl} />
+            {mapNode.modelUrl ? (
+              <Suspense fallback={<FallbackMapNode node={mapNode.node} />}>
+                <ModelInstance
+                  node={mapNode.node}
+                  modelUrl={mapNode.modelUrl}
+                />
+              </Suspense>
+            ) : (
+              <FallbackMapNode node={mapNode.node} />
+            )}
           </ModelErrorBoundary>
         ))}
       </group>
+      <GameMapCollision
+        mapReady={mapReady}
+        nodes={mapNodes}
+        onLoaded={onLoaded}
+        onLoadingStateChange={onLoadingStateChange}
+        onOctreeReady={onOctreeReady}
+      />
+    </>
   );
 }
 
@@ -147,3 +232,14 @@ function ModelInstance({
     />
   );
 }
+
+function FallbackMapNode({ node }: { node: MapNode }): React.JSX.Element {
+  const { position, rotation, scale } = node;
+
+  return (
+    <mesh position={position} rotation={rotation} scale={scale}>
+      <boxGeometry args={[1, 1, 1]} />
+      <meshStandardMaterial color="#64748b" wireframe />
+    </mesh>
+  );
+}

src/world/GameMapCollision.tsx

@@ -0,0 +1,212 @@
+import type { ReactNode } from "react";
+import {
+  Component,
+  Suspense,
+  useCallback,
+  useEffect,
+  useRef,
+  useState,
+} from "react";
+import * as THREE from "three";
+import { useClonedObject } from "@/hooks/three/useClonedObject";
+import { useLoggedGLTF } from "@/hooks/three/useLoggedGLTF";
+import { useOctreeGraphNode } from "@/hooks/three/useOctreeGraphNode";
+import type { MapNode } from "@/types/editor/editor";
+import type { OctreeReadyHandler } from "@/types/three/three";
+import type { SceneLoadingChangeHandler } from "@/types/world/sceneLoading";
+import { logModelLoadError } from "@/utils/three/modelLoadLogger";
+
+export interface GameMapCollisionNode {
+  node: MapNode;
+  modelUrl: string | null;
+}
+
+interface ResolvedGameMapCollisionNode {
+  node: MapNode;
+  modelUrl: string;
+}
+
+interface GameMapCollisionProps {
+  mapReady: boolean;
+  nodes: readonly GameMapCollisionNode[];
+  onLoaded?: (() => void) | undefined;
+  onLoadingStateChange?: SceneLoadingChangeHandler | undefined;
+  onOctreeReady: OctreeReadyHandler;
+}
+
+interface CollisionErrorBoundaryProps {
+  children: ReactNode;
+  modelUrl: string;
+  node: MapNode;
+  onSettled: () => void;
+}
+
+interface CollisionErrorBoundaryState {
+  hasError: boolean;
+}
+
+const MAP_COLLISION_NODE_NAMES = new Set(["terrain"]);
+
+class CollisionErrorBoundary extends Component<
+  CollisionErrorBoundaryProps,
+  CollisionErrorBoundaryState
+> {
+  constructor(props: CollisionErrorBoundaryProps) {
+    super(props);
+    this.state = { hasError: false };
+  }
+
+  static getDerivedStateFromError(): CollisionErrorBoundaryState {
+    return { hasError: true };
+  }
+
+  componentDidCatch(error: Error): void {
+    logModelLoadError(
+      {
+        modelPath: this.props.modelUrl,
+        scope: "GameMapCollision.ModelInstance",
+        position: this.props.node.position,
+        rotation: this.props.node.rotation,
+        scale: this.props.node.scale,
+      },
+      error,
+    );
+    this.props.onSettled();
+  }
+
+  render(): ReactNode {
+    if (this.state.hasError) {
+      return null;
+    }
+
+    return this.props.children;
+  }
+}
+
+function isCollisionNode(
+  mapNode: GameMapCollisionNode,
+): mapNode is ResolvedGameMapCollisionNode {
+  return (
+    mapNode.modelUrl !== null && MAP_COLLISION_NODE_NAMES.has(mapNode.node.name)
+  );
+}
+
+export function GameMapCollision({
+  mapReady,
+  nodes,
+  onLoaded,
+  onLoadingStateChange,
+  onOctreeReady,
+}: GameMapCollisionProps): React.JSX.Element {
+  const groupRef = useRef<THREE.Group>(null);
+  const settledCollisionNodesRef = useRef(new Set<number>());
+  const [settledCollisionNodeCount, setSettledCollisionNodeCount] = useState(0);
+  const collisionNodes = nodes.filter(isCollisionNode);
+  const collisionReady =
+    mapReady && settledCollisionNodeCount >= collisionNodes.length;
+
+  const handleCollisionNodeSettled = useCallback((index: number) => {
+    if (settledCollisionNodesRef.current.has(index)) return;
+
+    settledCollisionNodesRef.current.add(index);
+    setSettledCollisionNodeCount(settledCollisionNodesRef.current.size);
+  }, []);
+
+  const handleOctreeReady = useCallback<OctreeReadyHandler>(
+    (octree) => {
+      onLoadingStateChange?.({
+        currentStep: "Collision prête",
+        progress: 0.92,
+        status: "loading",
+      });
+      onOctreeReady(octree);
+      onLoaded?.();
+    },
+    [onLoaded, onLoadingStateChange, onOctreeReady],
+  );
+
+  useOctreeGraphNode(
+    groupRef,
+    handleOctreeReady,
+    collisionReady ? collisionNodes.length : 0,
+    collisionReady && collisionNodes.length > 0,
+  );
+
+  useEffect(() => {
+    if (!mapReady) return;
+
+    if (collisionNodes.length === 0) {
+      onLoaded?.();
+      return;
+    }
+
+    if (collisionReady) return;
+
+    onLoadingStateChange?.({
+      currentStep: "Ajout de la collision",
+      progress: 0.86,
+      status: "loading",
+    });
+  }, [
+    collisionNodes.length,
+    collisionReady,
+    mapReady,
+    onLoaded,
+    onLoadingStateChange,
+  ]);
+
+  return (
+    <group ref={groupRef} visible={false}>
+      {mapReady
+        ? collisionNodes.map((mapNode, index) => (
+            <CollisionErrorBoundary
+              key={`collision-${index}`}
+              node={mapNode.node}
+              modelUrl={mapNode.modelUrl}
+              onSettled={() => handleCollisionNodeSettled(index)}
+            >
+              <Suspense fallback={null}>
+                <CollisionModelInstance
+                  node={mapNode.node}
+                  modelUrl={mapNode.modelUrl}
+                  onLoaded={() => handleCollisionNodeSettled(index)}
+                />
+              </Suspense>
+            </CollisionErrorBoundary>
+          ))
+        : null}
+    </group>
+  );
+}
+
+function CollisionModelInstance({
+  node,
+  modelUrl,
+  onLoaded,
+}: {
+  node: MapNode;
+  modelUrl: string;
+  onLoaded: () => void;
+}): React.JSX.Element {
+  const { position, rotation, scale } = node;
+  const { scene } = useLoggedGLTF(modelUrl, {
+    scope: "GameMapCollision.ModelInstance",
+    position,
+    rotation,
+    scale,
+  });
+  const sceneInstance = useClonedObject(scene);
+
+  useEffect(() => {
+    onLoaded();
+  }, [onLoaded]);
+
+  return (
+    <primitive
+      object={sceneInstance}
+      position={position}
+      rotation={rotation}
+      scale={scale}
+    />
+  );
+}

src/world/World.tsx

@@ -1,6 +1,4 @@
-import { useState } from "react";
 import { Physics } from "@react-three/rapier";
-import type { Octree } from "three/addons/math/Octree.js";
 import {
   PLAYER_SPAWN_POSITION_GAME,
   PLAYER_SPAWN_POSITION_PHYSICS,
@@ -8,6 +6,7 @@ import {
 import { useCameraMode } from "@/hooks/debug/useCameraMode";
 import { useSceneMode } from "@/hooks/debug/useSceneMode";
 import { useHandTrackingSnapshot } from "@/hooks/handTracking/useHandTrackingSnapshot";
+import { useWorldSceneLoading } from "@/hooks/world/useWorldSceneLoading";
 import { DebugCameraControls } from "@/components/debug/scene/DebugCameraControls";
 import { DebugHelpers } from "@/components/debug/scene/DebugHelpers";
 import { HandTrackingGlove } from "@/components/three/handTracking/HandTrackingGlove";
@@ -18,12 +17,18 @@ import { GameMap } from "@/world/GameMap";
 import { GameStageContent } from "@/world/GameStageContent";
 import { Player } from "@/world/player/Player";
 import { TestMap } from "@/world/debug/TestMap";
+import type { SceneLoadingChangeHandler } from "@/types/world/sceneLoading";
 
-export function World(): React.JSX.Element {
+interface WorldProps {
+  onLoadingStateChange?: SceneLoadingChangeHandler | undefined;
+}
+
+export function World({ onLoadingStateChange }: WorldProps): React.JSX.Element {
   const cameraMode = useCameraMode();
   const sceneMode = useSceneMode();
   const { status, usageStatus } = useHandTrackingSnapshot();
-  const [octree, setOctree] = useState<Octree | null>(null);
+  const { octree, showGameStage, handleGameMapLoaded, handleOctreeReady } =
+    useWorldSceneLoading({ sceneMode, onLoadingStateChange });
   const playerSpawnPosition =
     sceneMode === "game"
       ? PLAYER_SPAWN_POSITION_GAME
@@ -47,13 +52,19 @@ export function World(): React.JSX.Element {
       {sceneMode === "game" ? (
         <>
           <GameMusic />
-          <GameMap onOctreeReady={setOctree} />
+          <GameMap
+            onLoaded={handleGameMapLoaded}
+            onLoadingStateChange={onLoadingStateChange}
+            onOctreeReady={handleOctreeReady}
+          />
+          {showGameStage ? (
             <Physics>
               <GameStageContent />
             </Physics>
+          ) : null}
         </>
       ) : (
-        <TestMap onOctreeReady={setOctree} />
+        <TestMap onOctreeReady={handleOctreeReady} />
       )}
       {cameraMode !== "debug" ? (
         <Player octree={octree} spawnPosition={playerSpawnPosition} />