diff --git a/src/components/three/gameplay/RepairGame.tsx b/src/components/three/gameplay/RepairGame.tsx
index b6b2827..81529ae 100644
--- a/src/components/three/gameplay/RepairGame.tsx
+++ b/src/components/three/gameplay/RepairGame.tsx
@@ -13,6 +13,7 @@ import { REPAIR_FRAGMENTATION_SEQUENCE_SECONDS } from "@/data/gameplay/repairGam
 import { REPAIR_MISSIONS } from "@/data/gameplay/repairMissions";
 import { useRepairFragmentationInput } from "@/hooks/gameplay/useRepairFragmentationInput";
 import { useRepairMissionStep } from "@/hooks/gameplay/useRepairMissionStep";
+import { useTerrainSnappedPosition } from "@/hooks/three/useTerrainHeight";
 import type {
   MissionStep,
   RepairMissionConfig,
@@ -66,6 +67,7 @@ export function RepairGame({
     readonly RepairScannedBrokenPart[]
   >([]);
   const parsedScale = toVector3Scale(scale);
+  const snappedPosition = useTerrainSnappedPosition(position);
   const readyForFragmentation = step === "inspected";
 
   useRepairFragmentationInput({
@@ -105,7 +107,7 @@ export function RepairGame({
   if (step === "locked") return null;
 
   return (
-    <group position={position} rotation={rotation} scale={parsedScale}>
+    <group position={snappedPosition} rotation={rotation} scale={parsedScale}>
       <Suspense fallback={null}>
         <RepairMissionAssetPreloader config={config} />
       </Suspense>
@@ -113,7 +115,7 @@ export function RepairGame({
         {step === "waiting" ? (
           <RepairInspectionObject
             config={config}
-            worldPosition={position}
+            worldPosition={snappedPosition}
             onInspect={() => setMissionStep(mission, "inspected")}
           />
         ) : null}
diff --git a/src/components/ui/debug/GameStateDebugPanel.tsx b/src/components/ui/debug/GameStateDebugPanel.tsx
index f7bcf43..3b87077 100644
--- a/src/components/ui/debug/GameStateDebugPanel.tsx
+++ b/src/components/ui/debug/GameStateDebugPanel.tsx
@@ -18,15 +18,15 @@ function toPascalCase(value: string): string {
 
 export function GameStateDebugPanel(): React.JSX.Element {
   const mainState = useGameStore((state) => state.mainState);
-  const bikeStep = useGameStore((state) => state.bike.currentStep);
+  const ebikeStep = useGameStore((state) => state.ebike.currentStep);
   const pyloneStep = useGameStore((state) => state.pylone.currentStep);
   const fermeStep = useGameStore((state) => state.ferme.currentStep);
   const detail = useGameStore((state) => {
     switch (state.mainState) {
       case "intro":
         return state.intro.currentStep;
-      case "bike":
-        return state.bike.currentStep;
+      case "ebike":
+        return state.ebike.currentStep;
       case "pylone":
         return state.pylone.currentStep;
       case "ferme":
@@ -37,7 +37,7 @@ export function GameStateDebugPanel(): React.JSX.Element {
   });
   const setMainState = useGameStore((state) => state.setMainState);
   const setIntroStep = useGameStore((state) => state.setIntroStep);
-  const setBikeState = useGameStore((state) => state.setBikeState);
+  const setEbikeState = useGameStore((state) => state.setEbikeState);
   const setPyloneState = useGameStore((state) => state.setPyloneState);
   const setFermeState = useGameStore((state) => state.setFermeState);
   const setOutroState = useGameStore((state) => state.setOutroState);
@@ -67,8 +67,8 @@ export function GameStateDebugPanel(): React.JSX.Element {
 
     if (!isMissionStep(nextSubState)) return;
 
-    if (mainState === "bike") {
-      setBikeState({ currentStep: nextSubState });
+    if (mainState === "ebike") {
+      setEbikeState({ currentStep: nextSubState });
       return;
     }
 
@@ -86,8 +86,8 @@ export function GameStateDebugPanel(): React.JSX.Element {
   function setDebugMainState(nextMainState: MainGameState): void {
     setMainState(nextMainState);
 
-    if (nextMainState === "bike" && bikeStep === "locked") {
-      setBikeState({ currentStep: "waiting" });
+    if (nextMainState === "ebike" && ebikeStep === "locked") {
+      setEbikeState({ currentStep: "waiting" });
       return;
     }
 
diff --git a/src/data/debug/testSceneConfig.ts b/src/data/debug/testSceneConfig.ts
index 3edd84b..4fb9c80 100644
--- a/src/data/debug/testSceneConfig.ts
+++ b/src/data/debug/testSceneConfig.ts
@@ -25,8 +25,8 @@ export const TEST_SCENE_REPAIR_ZONE_MARKER_TUBE_RADIUS = 0.045;
 
 export const TEST_SCENE_REPAIR_ZONES = [
   {
-    mission: "bike",
-    label: "Bike",
+    mission: "ebike",
+    label: "E-bike",
     color: "#38bdf8",
     position: [-12, 0, -12],
   },
@@ -43,7 +43,7 @@ export const TEST_SCENE_REPAIR_ZONES = [
     position: [12, 0, -12],
   },
 ] as const satisfies readonly {
-  mission: "bike" | "pylone" | "ferme";
+  mission: "ebike" | "pylone" | "ferme";
   label: string;
   color: string;
   position: Vector3Tuple;
diff --git a/src/data/gameplay/repairMissionAnchors.ts b/src/data/gameplay/repairMissionAnchors.ts
index 695025f..7edbe92 100644
--- a/src/data/gameplay/repairMissionAnchors.ts
+++ b/src/data/gameplay/repairMissionAnchors.ts
@@ -1,18 +1,18 @@
 import type { Vector3Tuple } from "@/types/three/three";
 import type { RepairMissionId } from "@/types/gameplay/repairMission";
 
-export const BIKE_REPAIR_POSITION = [
+export const EBIKE_REPAIR_POSITION = [
   42.2399, 4.5484, 34.6468,
 ] as const satisfies Vector3Tuple;
 
 const REPAIR_MISSION_POSITIONS = {
-  bike: BIKE_REPAIR_POSITION,
+  ebike: EBIKE_REPAIR_POSITION,
   pylone: [64, 0, -66],
   ferme: [-24, 0, 42],
 } as const satisfies Record<RepairMissionId, Vector3Tuple>;
 
 export const REPAIR_MISSION_POSITION_ENTRIES = [
-  { mission: "bike", position: REPAIR_MISSION_POSITIONS.bike },
+  { mission: "ebike", position: REPAIR_MISSION_POSITIONS.ebike },
   { mission: "pylone", position: REPAIR_MISSION_POSITIONS.pylone },
   { mission: "ferme", position: REPAIR_MISSION_POSITIONS.ferme },
 ] as const satisfies readonly {
diff --git a/src/data/gameplay/repairMissions.ts b/src/data/gameplay/repairMissions.ts
index 3e864ee..fcf49d9 100644
--- a/src/data/gameplay/repairMissions.ts
+++ b/src/data/gameplay/repairMissions.ts
@@ -14,8 +14,8 @@ const DEFAULT_REPAIR_CASE = {
 } satisfies RepairMissionCaseConfig;
 
 export const REPAIR_MISSIONS: Record<RepairMissionId, RepairMissionConfig> = {
-  bike: {
-    id: "bike",
+  ebike: {
+    id: "ebike",
     label: "E-bike",
     description:
       "Repair the damaged cooling module before relaunching the bike",
@@ -25,10 +25,10 @@ export const REPAIR_MISSIONS: Record<RepairMissionId, RepairMissionConfig> = {
     interactUiPath: REPAIR_INTERACT_UI_PATH,
     brokenUiPath: REPAIR_BROKEN_UI_PATH,
     case: DEFAULT_REPAIR_CASE,
-    requiredReplacementPartId: "bike-cooling-core-replacement",
+    requiredReplacementPartId: "ebike-cooling-core-replacement",
     brokenParts: [
       {
-        id: "bike-cooling-core",
+        id: "ebike-cooling-core",
         label: "Cooling core",
         modelPath: "/models/refroidisseur/model.gltf",
         nodeName: "refroidisseur",
@@ -37,17 +37,17 @@ export const REPAIR_MISSIONS: Record<RepairMissionId, RepairMissionConfig> = {
     ],
     replacementParts: [
       {
-        id: "bike-cooling-core-replacement",
+        id: "ebike-cooling-core-replacement",
         label: "Replacement cooling core",
         modelPath: "/models/refroidisseur/model.gltf",
       },
       {
-        id: "bike-radio-distractor",
+        id: "ebike-radio-distractor",
         label: "Radio module",
         modelPath: "/models/talkie/model.gltf",
       },
       {
-        id: "bike-glove-distractor",
+        id: "ebike-glove-distractor",
         label: "Insulation glove",
         modelPath: "/models/gant_l/model.gltf",
       },
diff --git a/src/data/world/terrainConfig.ts b/src/data/world/terrainConfig.ts
index bdce845..9cde64a 100644
--- a/src/data/world/terrainConfig.ts
+++ b/src/data/world/terrainConfig.ts
@@ -1,9 +1,15 @@
-import type { TerrainSurfaceColorConfig } from "@/types/world/terrainSurface";
+import type {
+  TerrainSurfaceColorConfig,
+  TerrainSurfaceProjectionConfig,
+} from "@/types/world/terrainSurface";
 
 export const TERRAIN_MODEL_PATH = "/models/terrain/model.gltf";
 export const TERRAIN_WATER_HEIGHT = 0.8;
 
-const TERRAIN_TILE_SIZE = 1;
+export const TERRAIN_TILE_SIZE = 1;
+export const TERRAIN_SURFACE_COLOR_TOLERANCE = 5;
+export const TERRAIN_SURFACE_PROJECTION =
+  {} satisfies TerrainSurfaceProjectionConfig;
 
 export const TERRAIN_COLORS = {
   grass1: {
@@ -54,3 +60,5 @@ export const TERRAIN_COLORS = {
     kind: "rock",
   },
 } satisfies Record<string, TerrainSurfaceColorConfig>;
+
+export type TerrainColorKey = keyof typeof TERRAIN_COLORS;
diff --git a/src/hooks/gameplay/useRepairMovementLocked.ts b/src/hooks/gameplay/useRepairMovementLocked.ts
index 11953ce..2d19c11 100644
--- a/src/hooks/gameplay/useRepairMovementLocked.ts
+++ b/src/hooks/gameplay/useRepairMovementLocked.ts
@@ -4,8 +4,8 @@ import type { MissionStep } from "@/types/gameplay/repairMission";
 export function useRepairMovementLocked(): boolean {
   return useGameStore((state) => {
     switch (state.mainState) {
-      case "bike":
-        return isRepairMovementLocked(state.bike.currentStep);
+      case "ebike":
+        return isRepairMovementLocked(state.ebike.currentStep);
       case "pylone":
         return isRepairMovementLocked(state.pylone.currentStep);
       case "ferme":
diff --git a/src/managers/stores/useGameStore.ts b/src/managers/stores/useGameStore.ts
index 9e89f26..2849702 100644
--- a/src/managers/stores/useGameStore.ts
+++ b/src/managers/stores/useGameStore.ts
@@ -26,7 +26,7 @@ interface IntroState {
   currentStep: GameStep;
   dialogueAudio: string | null;
   hasCompleted: boolean;
-  isBikeUnlocked: boolean;
+  isEbikeUnlocked: boolean;
 }
 
 interface MissionState {
@@ -46,7 +46,7 @@ export interface GameState {
   isCinematicPlaying: boolean;
   missionFlow: MissionFlowState;
   intro: IntroState;
-  bike: MissionState & {
+  ebike: MissionState & {
     isRepaired: boolean;
   };
   pylone: MissionState & {
@@ -70,13 +70,13 @@ interface GameActions {
   setIntroStep: (step: GameStep) => void;
   setIntroState: (intro: Partial<IntroState>) => void;
   setPlayerName: (playerName: string) => void;
-  setBikeState: (bike: Partial<GameState["bike"]>) => void;
+  setEbikeState: (ebike: Partial<GameState["ebike"]>) => void;
   setPyloneState: (pylone: Partial<GameState["pylone"]>) => void;
   setFermeState: (ferme: Partial<GameState["ferme"]>) => void;
   setOutroState: (outro: Partial<GameState["outro"]>) => void;
   setMissionStep: (mission: RepairMissionId, step: MissionStep) => void;
   completeIntro: () => void;
-  completeBike: () => void;
+  completeEbike: () => void;
   completePylone: () => void;
   completeFerme: () => void;
   completeMission: (mission: RepairMissionId) => void;
@@ -104,24 +104,24 @@ function isBoolean(value: unknown): value is boolean {
 
 function completeIntroState(state: GameState): GameStateUpdate {
   return {
-    mainState: "bike",
+    mainState: "ebike",
     intro: {
       ...state.intro,
       hasCompleted: true,
-      isBikeUnlocked: true,
+      isEbikeUnlocked: true,
     },
-    bike: {
-      ...state.bike,
+    ebike: {
+      ...state.ebike,
       currentStep: "locked",
     },
   };
 }
 
-function completeBikeState(state: GameState): GameStateUpdate {
+function completeEbikeState(state: GameState): GameStateUpdate {
   return {
     mainState: "pylone",
-    bike: {
-      ...state.bike,
+    ebike: {
+      ...state.ebike,
       currentStep: "done",
       isRepaired: true,
     },
@@ -180,8 +180,8 @@ function completeMissionState(
   mission: RepairMissionId,
 ): GameStateUpdate {
   switch (mission) {
-    case "bike":
-      return completeBikeState(state);
+    case "ebike":
+      return completeEbikeState(state);
     case "pylone":
       return completePyloneState(state);
     case "ferme":
@@ -236,9 +236,9 @@ function createInitialGameState(): GameState {
       currentStep: "intro",
       dialogueAudio: null,
       hasCompleted: false,
-      isBikeUnlocked: false,
+      isEbikeUnlocked: false,
     },
-    bike: {
+    ebike: {
       currentStep: "locked",
       dialogueAudio: null,
       isRepaired: false,
@@ -273,9 +273,9 @@ function hydrateIntroState(initial: IntroState, value: unknown): IntroState {
     hasCompleted: isBoolean(value.hasCompleted)
       ? value.hasCompleted
       : initial.hasCompleted,
-    isBikeUnlocked: isBoolean(value.isBikeUnlocked)
-      ? value.isBikeUnlocked
-      : initial.isBikeUnlocked,
+    isEbikeUnlocked: isBoolean(value.isEbikeUnlocked)
+      ? value.isEbikeUnlocked
+      : initial.isEbikeUnlocked,
   };
 }
 
@@ -320,7 +320,7 @@ function hydrateMissionFlowState(
 function hydrateDebugGameState(initial: GameState, value: unknown): GameState {
   if (!isRecord(value)) return initial;
 
-  const bike = hydrateMissionState(initial.bike, value.bike);
+  const ebike = hydrateMissionState(initial.ebike, value.ebike);
   const pylone = hydrateMissionState(initial.pylone, value.pylone);
   const ferme = hydrateMissionState(initial.ferme, value.ferme);
   const outro = isRecord(value.outro) ? value.outro : null;
@@ -337,12 +337,12 @@ function hydrateDebugGameState(initial: GameState, value: unknown): GameState {
       value.missionFlow,
     ),
     intro: hydrateIntroState(initial.intro, value.intro),
-    bike: {
-      ...bike,
+    ebike: {
+      ...ebike,
       isRepaired:
-        isRecord(value.bike) && isBoolean(value.bike.isRepaired)
-          ? value.bike.isRepaired
-          : initial.bike.isRepaired,
+        isRecord(value.ebike) && isBoolean(value.ebike.isRepaired)
+          ? value.ebike.isRepaired
+          : initial.ebike.isRepaired,
     },
     pylone: {
       ...pylone,
@@ -384,7 +384,7 @@ function pickGameState(state: GameStore): GameState {
     isCinematicPlaying: state.isCinematicPlaying,
     missionFlow: state.missionFlow,
     intro: state.intro,
-    bike: state.bike,
+    ebike: state.ebike,
     pylone: state.pylone,
     ferme: state.ferme,
     outro: state.outro,
@@ -415,8 +415,8 @@ export const useGameStore = create<GameStore>()((set) => ({
     set((state) => ({
       missionFlow: { ...state.missionFlow, playerName },
     })),
-  setBikeState: (bike) =>
-    set((state) => ({ bike: { ...state.bike, ...bike } })),
+  setEbikeState: (ebike) =>
+    set((state) => ({ ebike: { ...state.ebike, ...ebike } })),
   setPyloneState: (pylone) =>
     set((state) => ({ pylone: { ...state.pylone, ...pylone } })),
   setFermeState: (ferme) =>
@@ -426,7 +426,7 @@ export const useGameStore = create<GameStore>()((set) => ({
   setMissionStep: (mission, step) =>
     set((state) => setMissionStepState(state, mission, step)),
   completeIntro: () => set(completeIntroState),
-  completeBike: () => set((state) => completeMissionState(state, "bike")),
+  completeEbike: () => set((state) => completeMissionState(state, "ebike")),
   completePylone: () => set((state) => completeMissionState(state, "pylone")),
   completeFerme: () => set((state) => completeMissionState(state, "ferme")),
   completeMission: (mission) =>
diff --git a/src/providers/gameplay/HandTrackingProvider.tsx b/src/providers/gameplay/HandTrackingProvider.tsx
index a5993f9..4fd56f9 100644
--- a/src/providers/gameplay/HandTrackingProvider.tsx
+++ b/src/providers/gameplay/HandTrackingProvider.tsx
@@ -26,8 +26,8 @@ export function HandTrackingProvider({
   const sceneMode = useSceneMode();
   const repairNeedsHands = useGameStore((state) => {
     switch (state.mainState) {
-      case "bike":
-        return REPAIR_HAND_TRACKING_STEPS.has(state.bike.currentStep);
+      case "ebike":
+        return REPAIR_HAND_TRACKING_STEPS.has(state.ebike.currentStep);
       case "pylone":
         return REPAIR_HAND_TRACKING_STEPS.has(state.pylone.currentStep);
       case "ferme":
diff --git a/src/types/game.ts b/src/types/game.ts
index dd2a56c..5813d01 100644
--- a/src/types/game.ts
+++ b/src/types/game.ts
@@ -27,11 +27,11 @@ export const GAME_STEPS: readonly GameStep[] = [
 
 const GAME_STEP_VALUES: ReadonlySet<string> = new Set(GAME_STEPS);
 
-export type MainGameState = "intro" | "bike" | "pylone" | "ferme" | "outro";
+export type MainGameState = "intro" | "ebike" | "pylone" | "ferme" | "outro";
 
 export const MAIN_GAME_STATES: readonly MainGameState[] = [
   "intro",
-  "bike",
+  "ebike",
   "pylone",
   "ferme",
   "outro",
diff --git a/src/types/gameplay/repairMission.ts b/src/types/gameplay/repairMission.ts
index e82b5d0..2f8b0ad 100644
--- a/src/types/gameplay/repairMission.ts
+++ b/src/types/gameplay/repairMission.ts
@@ -4,7 +4,7 @@ import type {
   Vector3Tuple,
 } from "@/types/three/three";
 
-export type RepairMissionId = "bike" | "pylone" | "ferme";
+export type RepairMissionId = "ebike" | "pylone" | "ferme";
 
 export interface RepairMissionCaseConfig {
   position: Vector3Tuple;
@@ -54,7 +54,7 @@ export type MissionStep =
   | "reassembling"
   | "done";
 
-const REPAIR_MISSION_IDS = ["bike", "pylone", "ferme"] as const;
+const REPAIR_MISSION_IDS = ["ebike", "pylone", "ferme"] as const;
 const REPAIR_MISSION_ID_VALUES: ReadonlySet<string> = new Set(
   REPAIR_MISSION_IDS,
 );
diff --git a/src/types/world/terrainSurface.ts b/src/types/world/terrainSurface.ts
index aa6a812..1984c77 100644
--- a/src/types/world/terrainSurface.ts
+++ b/src/types/world/terrainSurface.ts
@@ -1,4 +1,6 @@
-type TerrainSurfaceKind =
+import type * as THREE from "three";
+
+export type TerrainSurfaceKind =
   | "grass"
   | "path"
   | "water"
@@ -6,7 +8,19 @@ type TerrainSurfaceKind =
   | "dirt"
   | "rock";
 
-type TerrainSurfaceRgb = readonly [number, number, number];
+export type TerrainSurfaceRgb = readonly [number, number, number];
+
+export interface TerrainSurfaceUv {
+  u: number;
+  v: number;
+}
+
+export interface TerrainSurfaceProjectionConfig {
+  flipX?: boolean;
+  flipZ?: boolean;
+  offsetX?: number;
+  offsetZ?: number;
+}
 
 export interface TerrainSurfaceBounds {
   minX: number;
@@ -23,3 +37,15 @@ export interface TerrainSurfaceColorConfig {
   modelPath?: string;
   tileSize?: number;
 }
+
+export interface TerrainSurfaceSample {
+  rgb: TerrainSurfaceRgb;
+  key: string | null;
+  config: TerrainSurfaceColorConfig | null;
+}
+
+export interface TerrainSurfaceData {
+  bounds: TerrainSurfaceBounds;
+  imageData: ImageData;
+  raycastTarget: THREE.Object3D;
+}
diff --git a/src/world/GameMap.tsx b/src/world/GameMap.tsx
index 2af7b0a..132a102 100644
--- a/src/world/GameMap.tsx
+++ b/src/world/GameMap.tsx
@@ -301,9 +301,9 @@ function MapNodeInstance({
 }): React.JSX.Element | null {
   const isGeneratedModel = isGeneratedMapModelName(node.name);
   const mainState = useGameStore((state) => state.mainState);
-  const bikeStep = useGameStore((state) => state.bike.currentStep);
+  const ebikeStep = useGameStore((state) => state.ebike.currentStep);
   const hideEbikeMapModel =
-    node.name === "ebike" && mainState === "bike" && bikeStep !== "locked";
+    node.name === "ebike" && mainState === "ebike" && ebikeStep !== "locked";
 
   useEffect(() => {
     if (modelUrl !== null || isGeneratedModel) return;
diff --git a/src/world/GameStageContent.tsx b/src/world/GameStageContent.tsx
index 1a5ab4a..e1f36c7 100644
--- a/src/world/GameStageContent.tsx
+++ b/src/world/GameStageContent.tsx
@@ -1,7 +1,7 @@
 import { InteractableObject } from "@/components/three/interaction/InteractableObject";
 import { RepairGame } from "@/components/three/gameplay/RepairGame";
 import {
-  BIKE_REPAIR_POSITION,
+  EBIKE_REPAIR_POSITION,
   REPAIR_MISSION_POSITION_ENTRIES,
 } from "@/data/gameplay/repairMissionAnchors";
 import { useGameStore } from "@/managers/stores/useGameStore";
@@ -34,19 +34,19 @@ function StageAnchor({
 
 function EbikeMissionTrigger(): React.JSX.Element | null {
   const mainState = useGameStore((state) => state.mainState);
-  const bikeStep = useGameStore((state) => state.bike.currentStep);
+  const ebikeStep = useGameStore((state) => state.ebike.currentStep);
   const setMissionStep = useGameStore((state) => state.setMissionStep);
 
-  if (mainState !== "bike" || bikeStep !== "locked") return null;
+  if (mainState !== "ebike" || ebikeStep !== "locked") return null;
 
   return (
-    <group position={BIKE_REPAIR_POSITION}>
+    <group position={EBIKE_REPAIR_POSITION}>
       <InteractableObject
         kind="trigger"
         label="Réparer l'e-bike"
-        position={BIKE_REPAIR_POSITION}
+        position={EBIKE_REPAIR_POSITION}
         radius={4}
-        onPress={() => setMissionStep("bike", "waiting")}
+        onPress={() => setMissionStep("ebike", "waiting")}
       >
         <mesh>
           <sphereGeometry args={[1.3, 16, 16]} />