well, that works

engine/Entity.ts

@@ -16,6 +16,10 @@ export type EntityInstance = {
 	sprite: Sprite;
 };
 
+export type Draw = (ctx: CanvasRenderingContext2D) => void;
+
+export type Process = (delta: number) => void;
+
 export function createEntity(
 	id: string,
 	src: string,
@@ -25,12 +29,33 @@ export function createEntity(
 	return { id, width, height, src };
 }
 
-export async function loadEntity(name: string): Promise<EntityInstance> {
-	const entity = (await import(`#/entities/${name}/index.ts`)).default;
+export const entityMap = new Map<string, EntityInstance>();
+export const entityDrawMap = new Map<string, Draw>();
+export const entityProcessMap = new Map<string, Process>();
 
-	const { width, height } = entity;
-	const sprite = createSprite(await loadImage(entity.src), 2, 4);
-	const position = createVector();
+export async function useEntity(data: Entity): Promise<{
+	draw: (fn: Draw) => void;
+	process: (fn: Process) => void;
+	entity: EntityInstance;
+}> {
+	const sprite = createSprite(await loadImage(data.src), 2, 4);
 
-	return { position, width, height, sprite };
+	const entity: EntityInstance = {
+		position: createVector(),
+		width: data.width,
+		height: data.height,
+		sprite,
+	};
+
+	entityMap.set(data.id, entity);
+
+	return {
+		draw(fn: Draw): void {
+			entityDrawMap.set(data.id, fn);
+		},
+		process(fn: Process): void {
+			entityProcessMap.set(data.id, fn);
+		},
+		entity,
+	};
 }

engine/Scene.ts

@@ -1,3 +1,12 @@
+import {
+	type Draw as EntityDraw,
+	type EntityInstance,
+	type Process as EntityProcess,
+	entityDrawMap,
+	entityMap,
+	entityProcessMap,
+} from "./Entity.ts";
+
 export type SceneData = {
 	id: string;
 	width: number;
@@ -7,6 +16,11 @@ export type SceneData = {
 
 export type Scene = {
 	data: SceneData;
+	entityPool: Array<{
+		draw: EntityDraw;
+		process: EntityProcess;
+		entity: EntityInstance;
+	}>;
 	process: Process;
 };
 
@@ -27,8 +41,21 @@ export const currentScene: Scene = {
 		entities: [],
 	},
 	process: () => {},
+	entityPool: [],
 };
 
+function drawEntities(ctx: CanvasRenderingContext2D): void {
+	for (const entity of currentScene.entityPool) {
+		entity.draw(ctx);
+	}
+}
+
+function processEntities(delta: number): void {
+	for (const entity of currentScene.entityPool) {
+		entity.process(delta);
+	}
+}
+
 export function useScene(data: SceneData): {
 	process: (fn: Process) => void;
 } {
@@ -36,7 +63,11 @@ export function useScene(data: SceneData): {
 
 	return {
 		process(fn: Process): void {
-			sceneProcessMap.set(data.id, fn);
+			sceneProcessMap.set(data.id, (ctx, delta) => {
+				drawEntities(ctx);
+				processEntities(delta);
+				fn(ctx, delta);
+			});
 		},
 	};
 }
@@ -57,6 +88,16 @@ export async function loadScene(name: string): Promise<void> {
 	const data = sceneDataMap.get(name)!;
 	currentScene.data = data;
 
+	for (const entity of data.entities) {
+		await import(`#/entities/${entity}/index.ts`);
+
+		currentScene.entityPool.push({
+			draw: entityDrawMap.get(entity)!,
+			process: entityProcessMap.get(entity)!,
+			entity: entityMap.get(entity)!,
+		});
+	}
+
 	const process = sceneProcessMap.get(name)!;
 	currentScene.process = process;
 }

entities/testEntity/index.ts

@@ -1,4 +1,11 @@
-import { createEntity } from "#/engine/Entity.ts";
+import { useEntity } from "#/engine/Entity.ts";
+import { drawSprite } from "#/lib/Sprite.ts";
 import data from "./data.json";
 
-export default createEntity(data.id, data.src, data.width, data.height);
+const { draw, process, entity } = await useEntity(data);
+
+draw((ctx: CanvasRenderingContext2D) => {
+	drawSprite(ctx, entity.sprite, 0, 0, 16, 16);
+});
+
+process((_delta) => {});

scenes/testScene/index.ts

@@ -1,18 +1,6 @@
-import { type EntityInstance, loadEntity } from "#/engine/Entity.ts";
 import { useScene } from "#/engine/Scene.ts";
-import { drawSprite } from "#/lib/Sprite.ts";
 import data from "./data.json";
 
 const { process } = useScene(data);
 
-const entities: Array<EntityInstance> = [];
-for (const entity of data.entities) {
-	const instance = await loadEntity(entity);
-	entities.push(instance);
-}
-
-process((ctx, _delta) => {
-	for (const instance of entities) {
-		drawSprite(ctx, instance.sprite, 0, 0, 16, 16);
-	}
-});
+process((_ctx, _delta) => {});