diff --git a/packages/frontend/src/pages/room.add-object-dialog.vue b/packages/frontend/src/pages/room.add-object-dialog.vue
index 9df0c6856a..1ccf981666 100644
--- a/packages/frontend/src/pages/room.add-object-dialog.vue
+++ b/packages/frontend/src/pages/room.add-object-dialog.vue
@@ -62,24 +62,29 @@ SPDX-License-Identifier: AGPL-3.0-only
 </template>
 
 <script setup lang="ts">
-import { ref, useTemplateRef, watch, onMounted, onUnmounted, reactive, nextTick, shallowRef, computed, triggerRef } from 'vue';
+import { ref, useTemplateRef, watch, onMounted, onUnmounted, reactive, nextTick, shallowRef, computed, triggerRef, markRaw } from 'vue';
 import XObjectCustomizeForm from './room.object-customize-form.vue';
 import XItem from './room.add-object-dialog.item.vue';
 import type { RoomObjectInstance, RoomStateObject } from '@/world/room/object.js';
+import type { PreviewEngineControllerOptions } from '@/world/room/previewEngineController.js';
 import { i18n } from '@/i18n.js';
 import MkModalWindow from '@/components/MkModalWindow.vue';
 import * as os from '@/os.js';
 import { OBJECT_DEFS } from '@/world/room/object-defs.js';
-import { createRoomObjectPreviewEngine, RoomObjectPreviewEngine } from '@/world/room/previewEngine.js';
 import { camelToKebab } from '@/world/utility.js';
 import MkButton from '@/components/MkButton.vue';
 import { prefer } from '@/preferences.js';
 import { deepClone } from '@/utility/clone.js';
 import { store } from '@/store.js';
 import MkFoldableSection from '@/components/MkFoldableSection.vue';
+import { PreviewEngineController } from '@/world/room/previewEngineController.js';
 
 // TODO: instanceのidと紛らわしいのでid -> typeにする
 
+const props = defineProps<{
+	graphicsQuality: number;
+}>();
+
 const emit = defineEmits<{
 	(ev: 'ok', ctx: {
 		id: string;
@@ -97,7 +102,15 @@ const selectedInstanceId = ref<string | null>(null);
 const selectedObjectOptionsState = ref<RoomStateObject | null>(null);
 const selectedObjectDef = computed(() => OBJECT_DEFS.find(def => def.id === selectedId.value) ?? null);
 const showObjectOptions = ref(false);
-const engine = shallowRef<RoomObjectPreviewEngine | null>(null);
+
+const previewEngineControllerOptions = computed<PreviewEngineControllerOptions>(() => ({
+	graphicsQuality: props.graphicsQuality,
+	fps: null,
+	resolution: 1,
+	workerMode: true,
+}));
+
+const controller = markRaw(new PreviewEngineController(previewEngineControllerOptions.value));
 
 const recentlyUsedDefs = computed(() => {
 	const recentlyUsed = store.s.recentlyUsedRoomObjects;
@@ -105,13 +118,23 @@ const recentlyUsedDefs = computed(() => {
 });
 
 onMounted(async () => {
-	engine.value = await createRoomObjectPreviewEngine(canvas.value!);
+	try {
+		await controller.init(canvas.value!);
+	} catch (err) {
+		console.error(err);
+		os.alert({
+			type: 'error',
+			title: i18n.ts._room.failedToInitialize,
+			text: (err instanceof Error ? err.message : String(err)),
+		});
+		return;
+	}
 
-	await engine.value.init();
+	canvas.value!.focus();
 });
 
 onUnmounted(() => {
-	engine.value.destroy();
+	controller.destroy();
 });
 
 watch(selectedId, (newId) => {
@@ -119,21 +142,21 @@ watch(selectedId, (newId) => {
 	showPreview.value = false;
 
 	if (newId == null) {
-		engine.value!.clear();
-		engine.value!.pauseRender();
+		controller.clearObject();
+		controller.pauseRender();
 		selectedInstanceId.value = null;
 		selectedObjectOptionsState.value = null;
 	} else {
 		const closeWaiting = os.waiting();
 		nextTick(() => {
-			engine.value!.load(newId).then(res => {
+			controller.loadObject(newId).then(res => {
 				selectedInstanceId.value = res.id;
 				selectedObjectOptionsState.value = deepClone(res.options);
-				engine.value!.resumeRender();
+				controller.resumeRender();
 				closeWaiting();
 				showPreview.value = true;
 				nextTick(() => {
-					engine.value!.resize();
+					controller.resize();
 				});
 			}).catch(err => {
 				console.error(err);
@@ -144,8 +167,8 @@ watch(selectedId, (newId) => {
 });
 
 function updateObjectOption(k: string, v: any) {
-	const updatedOptions = engine.value!.updateObjectOption(k, v);
-	selectedObjectOptionsState.value = deepClone(updatedOptions);
+	controller.updateObjectOption(k, v);
+	selectedObjectOptionsState.value![k] = v;
 }
 
 function ok() {
diff --git a/packages/frontend/src/world/controller.ts b/packages/frontend/src/world/controller.ts
index c064c2416f..68bdf65814 100644
--- a/packages/frontend/src/world/controller.ts
+++ b/packages/frontend/src/world/controller.ts
@@ -10,6 +10,7 @@ import type { ShallowRef } from 'vue';
 import * as sound from '@/utility/sound.js';
 
 // 抽象化レイヤー
+// TODO: 他のcontrollerと共通部分を抽出してabstract classを作ってそこから派生する形にする
 export class WorldController {
 	private worker: Worker | null = null;
 	private engine: WorldEngine | null = null;
@@ -50,9 +51,9 @@ export class WorldController {
 
 		this.canvas.addEventListener('keydown', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:keydown', ev: { code: ev.code, shiftKey: ev.shiftKey } });
+				this.worker.postMessage({ type: 'input:keydown', ev: { code: ev.code, shiftKey: ev.shiftKey } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('keydown', { code: ev.code, shiftKey: ev.shiftKey });
+				this.engine.inputs.emit('keydown', { code: ev.code, shiftKey: ev.shiftKey });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -61,9 +62,9 @@ export class WorldController {
 
 		this.canvas.addEventListener('keyup', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:keyup', ev: { code: ev.code, shiftKey: ev.shiftKey } });
+				this.worker.postMessage({ type: 'input:keyup', ev: { code: ev.code, shiftKey: ev.shiftKey } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('keyup', { code: ev.code, shiftKey: ev.shiftKey });
+				this.engine.inputs.emit('keyup', { code: ev.code, shiftKey: ev.shiftKey });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -76,9 +77,9 @@ export class WorldController {
 
 		this.canvas.addEventListener('wheel', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:wheel', ev: { deltaY: ev.deltaY } });
+				this.worker.postMessage({ type: 'input:wheel', ev: { deltaY: ev.deltaY } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('wheel', { deltaY: ev.deltaY });
+				this.engine.inputs.emit('wheel', { deltaY: ev.deltaY });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -107,9 +108,9 @@ export class WorldController {
 		this.canvas.addEventListener('click', (ev) => {
 			if (isDragging) return;
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:click', ev: { offsetX: ev.offsetX, offsetY: ev.offsetY } });
+				this.worker.postMessage({ type: 'input:click', ev: { offsetX: ev.offsetX, offsetY: ev.offsetY } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('click', { offsetX: ev.offsetX, offsetY: ev.offsetY });
+				this.engine.inputs.emit('click', { offsetX: ev.offsetX, offsetY: ev.offsetY });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
diff --git a/packages/frontend/src/world/engine.ts b/packages/frontend/src/world/engine.ts
index eb50b219fc..40fb2be3e5 100644
--- a/packages/frontend/src/world/engine.ts
+++ b/packages/frontend/src/world/engine.ts
@@ -49,7 +49,7 @@ export class WorldEngine extends EventEmitter<WorldEngineEvents> {
 	private fps: number | null = null;
 	private disposed = false;
 
-	public domEvents: EventEmitter<{
+	public inputs: EventEmitter<{
 		'click': (event: { offsetX: number; offsetY: number; }) => void;
 		'keydown': (event: { code: string; shiftKey: boolean; }) => void;
 		'keyup': (event: { code: string; shiftKey: boolean; }) => void;
@@ -230,15 +230,15 @@ export class WorldEngine extends EventEmitter<WorldEngineEvents> {
 			window.requestAnimationFrame(renderLoop);
 		}
 
-		this.domEvents.on('keydown', (ev) => {
+		this.inputs.on('keydown', (ev) => {
 		});
 
-		this.domEvents.on('wheel', (ev) => {
+		this.inputs.on('wheel', (ev) => {
 			this.camera.fov += ev.deltaY * 0.001;
 			this.camera.fov = Math.max(0.25, Math.min(1, this.camera.fov));
 		});
 
-		this.domEvents.on('click', (ev) => {
+		this.inputs.on('click', (ev) => {
 
 		});
 	}
diff --git a/packages/frontend/src/world/room/controller.ts b/packages/frontend/src/world/room/controller.ts
index 331de64ff8..aac32777dd 100644
--- a/packages/frontend/src/world/room/controller.ts
+++ b/packages/frontend/src/world/room/controller.ts
@@ -27,11 +27,13 @@ export type RoomControllerOptions = {
 };
 
 // 抽象化レイヤー
+// TODO: 他のcontrollerと共通部分を抽出してabstract classを作ってそこから派生する形にする
 export class RoomController {
 	private worker: Worker | null = null;
 	private engine: RoomEngine | null = null;
 	private canvas: HTMLCanvasElement | null = null;
 	private options: RoomControllerOptions;
+	private returnHooks = new Map<number, (value: any) => void>();
 	public isReady = ref(false);
 	public isSitting = ref(false);
 	public isEditMode = ref(false);
@@ -75,6 +77,15 @@ export class RoomController {
 						engineEvents.emit(type, ctx);
 						break;
 					}
+					case 'return': {
+						const { id, value } = event.data;
+						const hook = this.returnHooks.get(id);
+						if (hook != null) {
+							hook(value);
+							this.returnHooks.delete(id);
+						}
+						break;
+					}
 					default: {
 						console.warn('Unrecognized message from worker:', event.data?.type);
 					}
@@ -164,9 +175,9 @@ export class RoomController {
 
 		this.canvas.addEventListener('keydown', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:keydown', ev: { code: ev.code, shiftKey: ev.shiftKey } });
+				this.worker.postMessage({ type: 'input:keydown', ev: { code: ev.code, shiftKey: ev.shiftKey } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('keydown', { code: ev.code, shiftKey: ev.shiftKey });
+				this.engine.inputs.emit('keydown', { code: ev.code, shiftKey: ev.shiftKey });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -175,9 +186,9 @@ export class RoomController {
 
 		this.canvas.addEventListener('keyup', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:keyup', ev: { code: ev.code, shiftKey: ev.shiftKey } });
+				this.worker.postMessage({ type: 'input:keyup', ev: { code: ev.code, shiftKey: ev.shiftKey } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('keyup', { code: ev.code, shiftKey: ev.shiftKey });
+				this.engine.inputs.emit('keyup', { code: ev.code, shiftKey: ev.shiftKey });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -186,9 +197,9 @@ export class RoomController {
 
 		this.canvas.addEventListener('wheel', (ev) => {
 			if (this.worker != null) {
-				this.worker.postMessage({ type: 'dom:wheel', ev: { deltaY: ev.deltaY } });
+				this.worker.postMessage({ type: 'input:wheel', ev: { deltaY: ev.deltaY } });
 			} else if (this.engine != null) {
-				this.engine.domEvents.emit('wheel', { deltaY: ev.deltaY });
+				this.engine.inputs.emit('wheel', { deltaY: ev.deltaY });
 			}
 			ev.preventDefault();
 			ev.stopPropagation();
@@ -231,9 +242,9 @@ export class RoomController {
 				if (prevTwoTouchPointsDistance > 0) {
 					const delta = distance - prevTwoTouchPointsDistance;
 					if (this.worker != null) {
-						this.worker.postMessage({ type: 'dom:wheel', ev: { deltaY: -delta * 3 } });
+						this.worker.postMessage({ type: 'input:wheel', ev: { deltaY: -delta * 3 } });
 					} else if (this.engine != null) {
-						this.engine.domEvents.emit('wheel', { deltaY: -delta * 3 });
+						this.engine.inputs.emit('wheel', { deltaY: -delta * 3 });
 					}
 				}
 				prevTwoTouchPointsDistance = distance;
@@ -284,9 +295,9 @@ export class RoomController {
 				if (dx < 10 && dy < 10) {
 					const median = { x: (ev.offsetX + this.pointerDownPosition.x) / 2, y: (ev.offsetY + this.pointerDownPosition.y) / 2 };
 					if (this.worker != null) {
-						this.worker.postMessage({ type: 'dom:click', ev: { x: median.x, y: median.y } });
+						this.worker.postMessage({ type: 'input:click', ev: { x: median.x, y: median.y } });
 					} else if (this.engine != null) {
-						this.engine.domEvents.emit('click', { x: median.x, y: median.y });
+						this.engine.inputs.emit('click', { x: median.x, y: median.y });
 					}
 				}
 			}
@@ -309,12 +320,24 @@ export class RoomController {
 		await this.init(canvas ?? this.canvas!);
 	}
 
+	private callCounter = 0;
+
 	// TODO: いい感じに型付け
-	private call(fn, args = []) {
+	private call(fn, args = [], needReturnValue = false) {
 		if (this.worker != null) {
-			this.worker.postMessage({ type: 'call', fn, args });
+			if (needReturnValue) {
+				return new Promise((resolve) => {
+					const id = this.callCounter++;
+					this.returnHooks.set(id, (value) => {
+						resolve(value);
+					});
+					this.worker!.postMessage({ type: 'call', fn, args, needReturnValue: true, id });
+				});
+			} else {
+				this.worker.postMessage({ type: 'call', fn, args });
+			}
 		} else if (this.engine != null) {
-			this.engine[fn](...args);
+			return this.engine[fn](...args);
 		}
 	}
 
diff --git a/packages/frontend/src/world/room/engine.ts b/packages/frontend/src/world/room/engine.ts
index a54ead8f32..cbb9fd403a 100644
--- a/packages/frontend/src/world/room/engine.ts
+++ b/packages/frontend/src/world/room/engine.ts
@@ -202,7 +202,7 @@ export class RoomEngine extends EventEmitter {
 	private fps: number | null = null;
 	private disposed = false;
 
-	public domEvents: EventEmitter<{
+	public inputs: EventEmitter<{
 		'click': (event: { x: number; y: number; }) => void;
 		'keydown': (event: { code: string; shiftKey: boolean; }) => void;
 		'keyup': (event: { code: string; shiftKey: boolean; }) => void;
@@ -394,8 +394,8 @@ export class RoomEngine extends EventEmitter {
 
 		const box = BABYLON.MeshBuilder.CreateBox('', { size: cm(10) }, this.scene);
 		window.setInterval(() => {
-        box.position = new BABYLON.Vector3(0, Math.random() * cm(10), 0);
-    }, 10);
+			box.position = new BABYLON.Vector3(0, Math.random() * cm(10), 0);
+		}, 10);
 
 		this.startRenderLoop();
 
@@ -404,7 +404,7 @@ export class RoomEngine extends EventEmitter {
 		// 必ずシーンが少なくとも1フレームレンダリングがされてから呼ばれるように注意すること。そうしないとタイミングによってはエンジンがクラッシュする
 		this.sr.enableSnapshotRendering();
 
-		this.domEvents.on('keydown', (ev) => {
+		this.inputs.on('keydown', (ev) => {
 			if (ev.code === 'KeyE') {
 				if (this.isEditMode) {
 					if (this.grabbingCtx != null) {
@@ -432,7 +432,7 @@ export class RoomEngine extends EventEmitter {
 			}
 		});
 
-		this.domEvents.on('wheel', (ev) => {
+		this.inputs.on('wheel', (ev) => {
 			if (this.grabbingCtx != null) {
 				this.changeGrabbingDistance(ev.deltaY * 0.025);
 			} else {
@@ -441,7 +441,7 @@ export class RoomEngine extends EventEmitter {
 			}
 		});
 
-		this.domEvents.on('click', (ev) => {
+		this.inputs.on('click', (ev) => {
 			if (this.grabbingCtx != null) return;
 
 			this.selectObject(null);
@@ -454,7 +454,7 @@ export class RoomEngine extends EventEmitter {
 				const oid = pickingInfo.pickedMesh.metadata.objectId;
 				if (oid != null && this.objectEntities.has(oid)) {
 					const o = this.objectEntities.get(oid)!;
-					const boundingInfo = getMeshesBoundingBox(o.rootMesh.getChildMeshes().filter(m => m.isEnabled() && m.isVisible && !m.isDisposed()));
+					const boundingInfo = getMeshesBoundingBox(o.rootMesh.getChildMeshes().filter(m => m.isEnabled() && m.isVisible && !m.isDisposed()), true);
 					this.selectObject(oid);
 
 					{ // camera animation
diff --git a/packages/frontend/src/world/room/previewEngine.ts b/packages/frontend/src/world/room/previewEngine.ts
index f187c6ba6f..52e78439c3 100644
--- a/packages/frontend/src/world/room/previewEngine.ts
+++ b/packages/frontend/src/world/room/previewEngine.ts
@@ -6,24 +6,15 @@
 import * as BABYLON from '@babylonjs/core';
 import { registerBuiltInLoaders } from '@babylonjs/loaders/dynamic.js';
 import { GridMaterial } from '@babylonjs/materials';
-import { camelToKebab, WORLD_SCALE, cm, getMeshesBoundingBox, Timer, sleep } from '../utility.js';
+import EventEmitter from 'eventemitter3';
+import { camelToKebab, WORLD_SCALE, cm, getMeshesBoundingBox, Timer, sleep, ArcRotateCameraManualInput } from '../utility.js';
 import { getObjectDef } from './object-defs.js';
 import { SYSTEM_MESH_NAMES, ModelManager, GRAPHICS_QUALITY } from './utility.js';
 import type { RoomObjectInstance } from './object.js';
 import { genId } from '@/utility/id.js';
 import { deepClone } from '@/utility/clone.js';
-import { store } from '@/store.js';
 
-export async function createRoomObjectPreviewEngine(canvas: HTMLCanvasElement) {
-	const babylonEngine = new BABYLON.WebGPUEngine(canvas, { doNotHandleContextLost: true, powerPreference: 'low-power' });
-	babylonEngine.compatibilityMode = false;
-	babylonEngine.enableOfflineSupport = false;
-	await babylonEngine.initAsync();
-	return new RoomObjectPreviewEngine({ canvas, engine: babylonEngine });
-}
-
-export class RoomObjectPreviewEngine {
-	private canvas: HTMLCanvasElement;
+export class RoomObjectPreviewEngine extends EventEmitter {
 	private engine: BABYLON.WebGPUEngine;
 	private scene: BABYLON.Scene;
 	private sr: BABYLON.SnapshotRenderingHelper;
@@ -38,17 +29,29 @@ export class RoomObjectPreviewEngine {
 	private zGridPreviewPlane: BABYLON.Mesh;
 	private timerForEachObject: Timer | null = null;
 	private pipeline: BABYLON.DefaultRenderingPipeline;
+	private graphicsQuality: number;
 	private fps: number | null = null;
 	private disposed = false;
 
+	public inputs: EventEmitter<{
+		'click': (event: { x: number; y: number; }) => void;
+		'keydown': (event: { code: string; shiftKey: boolean; }) => void;
+		'keyup': (event: { code: string; shiftKey: boolean; }) => void;
+		'wheel': (event: { deltaY: number; }) => void;
+	}> = new EventEmitter();
+
 	constructor(options: {
-		canvas: HTMLCanvasElement;
 		engine: BABYLON.WebGPUEngine;
+		graphicsQuality: number;
+		fps: number | null;
 	}) {
-		this.canvas = options.canvas;
+		super();
 
 		registerBuiltInLoaders();
 
+		this.graphicsQuality = options.graphicsQuality;
+		this.fps = options.fps;
+
 		this.engine = options.engine;
 		this.scene = new BABYLON.Scene(this.engine);
 		this.scene.autoClear = false;
@@ -78,7 +81,7 @@ export class RoomObjectPreviewEngine {
 		this.shadowGenerator.getShadowMap().refreshRate = 60;
 
 		const gridMaterial = new GridMaterial('grid', this.scene);
-		gridMaterial.lineColor = store.s.darkMode ? new BABYLON.Color3(1, 1, 1) : new BABYLON.Color3(0, 0, 0);
+		gridMaterial.lineColor = new BABYLON.Color3(1, 1, 1);
 		gridMaterial.mainColor = new BABYLON.Color3(0, 0, 0);
 		gridMaterial.minorUnitVisibility = 1;
 		gridMaterial.opacity = 0.05;
@@ -97,16 +100,17 @@ export class RoomObjectPreviewEngine {
 
 		this.pipeline = new BABYLON.DefaultRenderingPipeline('default', true, this.scene);
 		this.pipeline.samples = 4;
-		// 重い
-		//this.pipeline.bloomEnabled = true;
-		//this.pipeline.bloomThreshold = 0.95;
-		//this.pipeline.bloomWeight = 0.1;
-		//this.pipeline.bloomKernel = 256;
-		//this.pipeline.bloomScale = 2;
+		if (this.graphicsQuality >= GRAPHICS_QUALITY.HIGH) {
+			this.pipeline.bloomEnabled = true;
+			this.pipeline.bloomThreshold = 0.95;
+			this.pipeline.bloomWeight = 0.1;
+			this.pipeline.bloomKernel = 256;
+			this.pipeline.bloomScale = 2;
+		}
 		this.pipeline.sharpenEnabled = true;
 		this.pipeline.sharpen.edgeAmount = 0.5;
 
-		if (_DEV_) {
+		if (_DEV_ && typeof window !== 'undefined') {
 			window.takeScreenshot = () => {
 				const def = getObjectDef(this.objectType);
 
@@ -190,11 +194,16 @@ export class RoomObjectPreviewEngine {
 	public async init() {
 		await this.scene.whenReadyAsync();
 		this.sr.enableSnapshotRendering();
+
+		this.inputs.on('wheel', (ev) => {
+			this.camera.fov += ev.deltaY * 0.001;
+			this.camera.fov = Math.max(0.25, Math.min(0.5, this.camera.fov));
+		});
 	}
 
-	public async load(type: string) {
+	public async loadObject(type: string) {
 		this.sr.disableSnapshotRendering();
-		this.clear();
+		this.clearObject();
 
 		const id = genId();
 		const def = getObjectDef(type);
@@ -205,7 +214,7 @@ export class RoomObjectPreviewEngine {
 			}
 		}
 
-		await this.loadObject({
+		await this.loadObject_({
 			type,
 			options: this.objectOptions,
 			id,
@@ -217,7 +226,6 @@ export class RoomObjectPreviewEngine {
 		this.camera.dispose();
 
 		this.camera = new BABYLON.ArcRotateCamera('camera', Math.PI / 2, Math.PI / 2.5, cm(300), new BABYLON.Vector3(0, cm(90), 0), this.scene);
-		this.camera.attachControl(this.canvas);
 		this.camera.minZ = cm(1);
 		this.camera.maxZ = cm(100000);
 		this.camera.fov = 0.5;
@@ -229,6 +237,11 @@ export class RoomObjectPreviewEngine {
 		this.camera.wheelDeltaPercentage = 0.01;
 		//this.camera.mode = BABYLON.Camera.ORTHOGRAPHIC_CAMERA;
 		this.camera.setTarget(new BABYLON.Vector3(0, boundingInfo.centerWorld.y, 0));
+		this.camera.inputs.clear();
+
+		this.camera.inputs.add(new ArcRotateCameraManualInput(this.scene, {
+			rotationSensitivity: 0.0005,
+		}));
 
 		if (def.placement === 'wall' || def.placement === 'side') {
 			this.camera.lowerBetaLimit = 0;
@@ -260,12 +273,11 @@ export class RoomObjectPreviewEngine {
 
 		return {
 			id,
-			objectInstance: this.objectInstance,
 			options: this.objectOptions,
 		};
 	}
 
-	private async loadObject(args: {
+	private async loadObject_(args: {
 		type: string;
 		options: any;
 		id: string;
@@ -365,7 +377,7 @@ export class RoomObjectPreviewEngine {
 		return this.objectOptions;
 	}
 
-	public clear() {
+	public clearObject() {
 		this.sr.disableSnapshotRendering();
 		if (this.timerForEachObject != null) {
 			this.timerForEachObject.dispose();
@@ -382,6 +394,10 @@ export class RoomObjectPreviewEngine {
 		this.sr.enableSnapshotRendering();
 	}
 
+	public cameraRotate(vector: { x: number; y: number; }) {
+		(this.camera.inputs.attached.manual as ArcRotateCameraManualInput).setRotationVector(vector);
+	}
+
 	public resize() {
 		// 一旦snapshot renderingを無効にしておかないとエラーが出る(babylonのバグ？)
 		// ~~...が、一旦無効にしたらしたで複数のマテリアルがそれぞれ入れ替わる(?)という謎の現象が発生するためコメントアウトしとく(エラー出てもレンダリングが止まったりするわけでもないし)~~
diff --git a/packages/frontend/src/world/room/previewEngineController.ts b/packages/frontend/src/world/room/previewEngineController.ts
new file mode 100644
index 0000000000..8ce46c2fb0
--- /dev/null
+++ b/packages/frontend/src/world/room/previewEngineController.ts
@@ -0,0 +1,293 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { reactive, ref, shallowRef, triggerRef, watch } from 'vue';
+import * as BABYLON from '@babylonjs/core';
+import { EventEmitter } from 'eventemitter3';
+import PreviewEngineWorker from './previewEngineWorker?worker';
+import { RoomObjectPreviewEngine } from './previewEngine.js';
+import type { ShallowRef } from 'vue';
+import type { RoomEngineEvents, RoomState } from './engine.js';
+import * as sound from '@/utility/sound.js';
+import * as os from '@/os.js';
+import { i18n } from '@/i18n.js';
+import { deepEqual } from '@/utility/deep-equal.js';
+
+export type PreviewEngineControllerOptions = {
+	workerMode?: boolean;
+	graphicsQuality: number;
+	fps: number | null;
+	resolution: number;
+};
+
+// 抽象化レイヤー
+// TODO: 他のcontrollerと共通部分を抽出してabstract classを作ってそこから派生する形にする
+export class PreviewEngineController {
+	private worker: Worker | null = null;
+	private engine: RoomObjectPreviewEngine | null = null;
+	private canvas: HTMLCanvasElement | null = null;
+	private options: PreviewEngineControllerOptions;
+	private returnHooks = new Map<number, (value: any) => void>();
+	public isReady = ref(false);
+	private pointerDownPosition: { x: number; y: number } | null = null;
+	private abortController = new AbortController();
+
+	constructor(options: PreviewEngineControllerOptions) {
+		this.options = options;
+	}
+
+	public async init(canvas: HTMLCanvasElement) {
+		this.canvas = canvas;
+		this.canvas.width = canvas.clientWidth;
+		this.canvas.height = canvas.clientHeight;
+
+		const engineEvents = new EventEmitter<RoomEngineEvents>();
+
+		if (this.options.workerMode) {
+			const offscreen = canvas.transferControlToOffscreen();
+			this.worker = new PreviewEngineWorker();
+			this.worker.postMessage({ type: 'init', canvas: offscreen, options: this.options }, [offscreen]);
+			this.worker.onmessage = (event) => {
+				switch (event.data?.type) {
+					case 'inited': {
+						this.isReady.value = true;
+						break;
+					}
+					case 'ev': {
+						const { type, ctx } = event.data.ev;
+						engineEvents.emit(type, ctx);
+						break;
+					}
+					case 'return': {
+						const { id, value } = event.data;
+						const hook = this.returnHooks.get(id);
+						if (hook != null) {
+							hook(value);
+							this.returnHooks.delete(id);
+						}
+						break;
+					}
+					default: {
+						console.warn('Unrecognized message from worker:', event.data?.type);
+					}
+				}
+			};
+		} else {
+			const babylonEngine = new BABYLON.WebGPUEngine(canvas, { doNotHandleContextLost: true, powerPreference: 'low-power', antialias: true });
+			babylonEngine.compatibilityMode = false;
+			babylonEngine.enableOfflineSupport = false;
+			babylonEngine.onContextLostObservable.add(() => {
+				os.alert({
+					type: 'error',
+					title: i18n.ts.somethingHappened,
+					text: i18n.ts._room.crushed_description,
+				});
+			});
+			await babylonEngine.initAsync();
+			if (this.options.resolution === 2) babylonEngine.setHardwareScalingLevel(0.5);
+			if (this.options.resolution === 0.5) babylonEngine.setHardwareScalingLevel(2);
+
+			this.engine = new RoomObjectPreviewEngine({
+				engine: babylonEngine,
+				...this.options,
+			});
+
+			this.engine.on('ev', ({ type, ctx }) => {
+				engineEvents.emit(type, ctx);
+			});
+
+			await this.engine.init();
+
+			this.isReady.value = true;
+		}
+
+		this.canvas.addEventListener('wheel', (ev) => {
+			if (this.worker != null) {
+				this.worker.postMessage({ type: 'input:wheel', ev: { deltaY: ev.deltaY } });
+			} else if (this.engine != null) {
+				this.engine.inputs.emit('wheel', { deltaY: ev.deltaY });
+			}
+			ev.preventDefault();
+			ev.stopPropagation();
+			return false;
+		}, { signal: this.abortController.signal });
+
+		const pointerEventCache = new Map<number, PointerEvent>();
+		let pointerVec = { x: 0, y: 0 };
+
+		this.canvas.addEventListener('pointerdown', (ev) => {
+			ev.preventDefault();
+			ev.stopPropagation();
+			this.canvas!.focus();
+			pointerEventCache.set(ev.pointerId, ev);
+			this.canvas!.setPointerCapture(ev.pointerId);
+
+			pointerVec = { x: ev.clientX, y: ev.clientY };
+
+			this.pointerDownPosition = { x: ev.offsetX, y: ev.offsetY };
+
+			return false;
+		}, { signal: this.abortController.signal });
+
+		let prevTwoTouchPointsDistance = 0;
+
+		this.canvas!.addEventListener('pointermove', (ev) => {
+			ev.preventDefault();
+			ev.stopPropagation();
+
+			if (pointerEventCache.size === 0) {
+				return;
+			}
+
+			pointerEventCache.set(ev.pointerId, ev);
+
+			if (pointerEventCache.size > 1) {
+				const a = Array.from(pointerEventCache.values())[0];
+				const b = Array.from(pointerEventCache.values())[1];
+				const distance = Math.hypot(a.clientX - b.clientX, a.clientY - b.clientY);
+				if (prevTwoTouchPointsDistance > 0) {
+					const delta = distance - prevTwoTouchPointsDistance;
+					if (this.worker != null) {
+						this.worker.postMessage({ type: 'input:wheel', ev: { deltaY: -delta * 3 } });
+					} else if (this.engine != null) {
+						this.engine.inputs.emit('wheel', { deltaY: -delta * 3 });
+					}
+				}
+				prevTwoTouchPointsDistance = distance;
+
+				pointerVec = { x: 0, y: 0 };
+				this.setCameraRotateVector({
+					x: 0,
+					y: 0,
+				});
+				return;
+			}
+
+			prevTwoTouchPointsDistance = 0;
+
+			const before = pointerVec;
+			const after = { x: ev.clientX, y: ev.clientY };
+
+			if (pointerVec.x !== 0 || pointerVec.y !== 0) {
+				this.setCameraRotateVector({
+					x: after.x - before.x,
+					y: after.y - before.y,
+				});
+			}
+
+			pointerVec.x = after.x;
+			pointerVec.y = after.y;
+
+			return false;
+		}, { signal: this.abortController.signal });
+
+		this.canvas.addEventListener('pointerup', (ev) => {
+			pointerEventCache.delete(ev.pointerId);
+			this.canvas!.releasePointerCapture(ev.pointerId);
+
+			prevTwoTouchPointsDistance = 0;
+
+			if (pointerEventCache.size > 0) {
+				return;
+			}
+
+			pointerVec.x = 0;
+			pointerVec.y = 0;
+			this.setCameraRotateVector(pointerVec);
+
+			if (this.pointerDownPosition != null) {
+				const dx = Math.abs(ev.offsetX - this.pointerDownPosition.x);
+				const dy = Math.abs(ev.offsetY - this.pointerDownPosition.y);
+				if (dx < 10 && dy < 10) {
+					const median = { x: (ev.offsetX + this.pointerDownPosition.x) / 2, y: (ev.offsetY + this.pointerDownPosition.y) / 2 };
+					if (this.worker != null) {
+						this.worker.postMessage({ type: 'input:click', ev: { x: median.x, y: median.y } });
+					} else if (this.engine != null) {
+						this.engine.inputs.emit('click', { x: median.x, y: median.y });
+					}
+				}
+			}
+			this.pointerDownPosition = null;
+		}, { signal: this.abortController.signal });
+	}
+
+	private callCounter = 0;
+
+	// TODO: いい感じに型付け
+	private call(fn, args = [], needReturnValue = false) {
+		if (this.worker != null) {
+			if (needReturnValue) {
+				return new Promise((resolve) => {
+					const id = this.callCounter++;
+					this.returnHooks.set(id, (value) => {
+						resolve(value);
+					});
+					this.worker!.postMessage({ type: 'call', fn, args, needReturnValue: true, id });
+				});
+			} else {
+				this.worker.postMessage({ type: 'call', fn, args });
+			}
+		} else if (this.engine != null) {
+			return this.engine[fn](...args);
+		}
+	}
+
+	// TODO: いい感じに型付け
+	private set(key, value) {
+		if (this.worker != null) {
+			this.worker.postMessage({ type: 'set', key, value });
+		} else if (this.engine != null) {
+			this.engine[key] = value;
+		}
+	}
+
+	public pauseRender() {
+		this.call('pauseRender');
+	}
+
+	public resumeRender() {
+		this.call('resumeRender');
+	}
+
+	public setCameraRotateVector(vec: { x: number; y: number }) {
+		this.call('cameraRotate', [vec]);
+	}
+
+	public updateObjectOption(key: string, value: any) {
+		this.call('updateObjectOption', [key, value]);
+	}
+
+	public loadObject(type: string) {
+		return this.call('loadObject', [type], true);
+	}
+
+	public clearObject() {
+		this.call('clearObject');
+	}
+
+	public resize() {
+		if (this.canvas == null) return;
+		const width = this.canvas.clientWidth;
+		const height = this.canvas.clientHeight;
+		if (this.worker != null) {
+			this.worker.postMessage({ type: 'resize', width, height });
+		} else if (this.engine != null) {
+			this.engine.resize();
+		}
+	}
+
+	public destroy() {
+		this.abortController.abort();
+
+		if (this.worker != null) {
+			this.worker.terminate();
+			this.worker = null;
+		}
+		if (this.engine != null) {
+			this.engine.destroy();
+			this.engine = null;
+		}
+	}
+}
diff --git a/packages/frontend/src/world/room/previewEngineWorker.ts b/packages/frontend/src/world/room/previewEngineWorker.ts
new file mode 100644
index 0000000000..6fde72ff36
--- /dev/null
+++ b/packages/frontend/src/world/room/previewEngineWorker.ts
@@ -0,0 +1,88 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import * as BABYLON from '@babylonjs/core';
+import { RoomObjectPreviewEngine } from './previewEngine.js';
+
+let engine: RoomObjectPreviewEngine | null = null;
+let canvas: OffscreenCanvas | null = null;
+
+onmessage = async (event) => {
+	//console.log('Worker received message:', event.data);
+
+	switch (event.data?.type) {
+		case 'init': {
+			canvas = event.data.canvas as OffscreenCanvas;
+			const babylonEngine = new BABYLON.WebGPUEngine(canvas, { doNotHandleContextLost: true, powerPreference: 'low-power', antialias: true });
+			babylonEngine.compatibilityMode = false;
+			babylonEngine.enableOfflineSupport = false;
+			await babylonEngine.initAsync();
+			if (event.data.options.resolution === 2) babylonEngine.setHardwareScalingLevel(0.5);
+			if (event.data.options.resolution === 0.5) babylonEngine.setHardwareScalingLevel(2);
+
+			engine = new RoomObjectPreviewEngine({
+				engine: babylonEngine,
+				...event.data.options,
+			});
+
+			engine.on('ev', ({ type, ctx }) => {
+				self.postMessage({ type: 'ev', ev: { type, ctx } });
+			});
+
+			await engine.init();
+
+			self.postMessage({ type: 'inited' });
+			break;
+		}
+		case 'resize': {
+			canvas.width = event.data.width;
+			canvas.height = event.data.height;
+			if (engine != null) engine.resize();
+			break;
+		}
+		case 'input:keydown': {
+			if (engine == null) break;
+			engine.inputs.emit('keydown', event.data.ev);
+			break;
+		}
+		case 'input:keyup': {
+			if (engine == null) break;
+			engine.inputs.emit('keyup', event.data.ev);
+			break;
+		}
+		case 'input:click': {
+			if (engine == null) break;
+			engine.inputs.emit('click', event.data.ev);
+			break;
+		}
+		case 'input:wheel': {
+			if (engine == null) break;
+			engine.inputs.emit('wheel', event.data.ev);
+			break;
+		}
+		case 'call': {
+			if (engine != null) {
+				const res = engine[event.data.fn](...(event.data.args ?? []));
+				if (event.data.needReturnValue) {
+					if (res instanceof Promise) {
+						res.then((r) => {
+							self.postMessage({ type: 'return', id: event.data.id, value: r });
+						});
+					} else {
+						self.postMessage({ type: 'return', id: event.data.id, value: res });
+					}
+				}
+			}
+			break;
+		}
+		case 'set': {
+			if (engine != null) engine[event.data.key] = event.data.value;
+			break;
+		}
+		default: {
+			console.warn('Unrecognized message type:', event.data?.type);
+		}
+	}
+};
diff --git a/packages/frontend/src/world/room/worker.ts b/packages/frontend/src/world/room/worker.ts
index 7fcaad4155..d25ff9773d 100644
--- a/packages/frontend/src/world/room/worker.ts
+++ b/packages/frontend/src/world/room/worker.ts
@@ -44,28 +44,39 @@ onmessage = async (event) => {
 			if (engine != null) engine.resize();
 			break;
 		}
-		case 'dom:keydown': {
+		case 'input:keydown': {
 			if (engine == null) break;
-			engine.domEvents.emit('keydown', event.data.ev);
+			engine.inputs.emit('keydown', event.data.ev);
 			break;
 		}
-		case 'dom:keyup': {
+		case 'input:keyup': {
 			if (engine == null) break;
-			engine.domEvents.emit('keyup', event.data.ev);
+			engine.inputs.emit('keyup', event.data.ev);
 			break;
 		}
-		case 'dom:click': {
+		case 'input:click': {
 			if (engine == null) break;
-			engine.domEvents.emit('click', event.data.ev);
+			engine.inputs.emit('click', event.data.ev);
 			break;
 		}
-		case 'dom:wheel': {
+		case 'input:wheel': {
 			if (engine == null) break;
-			engine.domEvents.emit('wheel', event.data.ev);
+			engine.inputs.emit('wheel', event.data.ev);
 			break;
 		}
 		case 'call': {
-			if (engine != null) engine[event.data.fn](...(event.data.args ?? []));
+			if (engine != null) {
+				const res = engine[event.data.fn](...(event.data.args ?? []));
+				if (event.data.needReturnValue) {
+					if (res instanceof Promise) {
+						res.then((r) => {
+							self.postMessage({ type: 'return', id: event.data.id, value: r });
+						});
+					} else {
+						self.postMessage({ type: 'return', id: event.data.id, value: res });
+					}
+				}
+			}
 			break;
 		}
 		case 'set': {
diff --git a/packages/frontend/src/world/utility.ts b/packages/frontend/src/world/utility.ts
index 6a22be41c5..626bc7c008 100644
--- a/packages/frontend/src/world/utility.ts
+++ b/packages/frontend/src/world/utility.ts
@@ -701,3 +701,38 @@ export class FreeCameraManualInput implements BABYLON.ICameraInput<BABYLON.FreeC
 		//this.camera.cameraDirection.addInPlace(this.camera._transformedDirection);
 	}
 }
+
+export class ArcRotateCameraManualInput implements BABYLON.ICameraInput<BABYLON.ArcRotateCamera> {
+	public camera: BABYLON.ArcRotateCamera;
+	private scene: BABYLON.Scene;
+	private rotationSensitivity: number;
+
+	constructor(scene: BABYLON.Scene, options: {
+		rotationSensitivity?: number;
+	}) {
+		this.scene = scene;
+		this.rotationSensitivity = options.rotationSensitivity ?? 0.01;
+	}
+
+	getClassName = () => this.constructor.name;
+
+	getSimpleName = () => 'manual';
+
+	attachControl(noPreventDefault) {
+	}
+
+	detachControl() {
+	}
+
+	public setRotationVector(vec: { x: number; y: number }) {
+		let directionAdjust = 1;
+		if (this.scene.useRightHandedSystem) directionAdjust *= -1;
+		if (this.camera.parent && this.camera.parent._getWorldMatrixDeterminant() < 0) directionAdjust *= -1;
+
+		this.camera.inertialBetaOffset += -vec.y * this.rotationSensitivity * directionAdjust;
+		this.camera.inertialAlphaOffset += -vec.x * this.rotationSensitivity * directionAdjust;
+	}
+
+	checkInputs() {
+	}
+}