init

server/engine.ts

@@ -0,0 +1,153 @@
+import { assertEquals } from "https://deno.land/std@0.221.0/assert/mod.ts";
+import { chunks, enumerate, log_from, Prototyped, range, Vec2 } from "../common/utils.ts";
+import { ClientInterface } from "./network.ts";
+import { Session } from "./entities/player.ts";
+import { ClassMap } from "../common/utils.ts";
+import { maybe } from "../common/utils.ts";
+const log = log_from(import.meta);
+
+export class WorldEntity {
+	display;
+	world;
+	identifier;
+	position;
+	compontents;
+
+	constructor(world: World, identifier: number, display: string, position: Vec2, ...components: Prototyped[]) {
+		this.display = display;
+		this.world = world;
+		this.identifier = identifier;
+		this.position = position;
+		this.compontents = new ClassMap();
+		for (const c of components) this.compontents.insert(c);
+	}
+}
+
+export class World {
+	next_id;
+	entities;
+
+	constructor() {
+		this.next_id = 0;
+		this.entities = new Map<number, WorldEntity>();
+	}
+
+	spawn_entity(display: string, pos: Vec2) {
+		const entity = new WorldEntity(this, this.next_id++, display, pos);
+		this.entities.set(entity.identifier, entity);
+		return entity;
+	}
+
+	async spawn_structure(file_path: string, origin: Vec2) {
+		const content = await Deno.readTextFile(file_path);
+		let count = 0;
+		for (const [y, line] of enumerate(content.split("\n"))) {
+			for (const [x, chars] of enumerate(chunks(line, 2))) {
+				const display = chars[0] + chars[1];
+				if (display === "  ") continue;
+				this.spawn_entity(display, origin.add(new Vec2(x, y)));
+				count += 1;
+			}
+		}
+		log("Spawned", count, "tiles from", file_path);
+	}
+
+	render(center: Vec2, size: Vec2) {
+		const radius = size.scale(0.5);
+		const result = Array.from(range(0, size.y())).map(() => Array.from(range(0, size.x())).map(() => "  "));
+		const top_left = center.sub(radius);
+		const bottom_right = center.add(radius);
+		for (const entity of this.entities.values()) {
+			if (!entity.position.inside(top_left, bottom_right)) continue;
+			const local_pos = entity.position.sub(top_left);
+			result[local_pos.y()][local_pos.x()] = entity.display;
+		}
+		return result.map((line) => line.join("")).toReversed().join("\n");
+	}
+
+	move_collide(entity_id: number, displacement: Vec2) {
+		let result = false;
+		const entity = this.get_entity(entity_id);
+		if (entity === undefined) return result;
+		for (const step of displacement_steps(entity.position, displacement)) {
+			const collision = this.get_entity_at(step);
+			if (collision !== undefined) return result;
+			entity.position = step;
+			result = true;
+		}
+		return result;
+	}
+
+	get_entity(entity_id: number) {
+		return this.entities.get(entity_id);
+	}
+
+	*get_entities_at(pos: Vec2) {
+		for (const entity of this.entities.values()) if (entity.position.overlaps(pos)) yield entity;
+	}
+
+	get_entity_at(pos: Vec2) {
+		return maybe([...this.get_entities_at(pos)][0]);
+	}
+
+	*get_entities_in_range(min: Vec2, max: Vec2) {
+		for (const entity of this.entities.values()) if (entity.position.inside(min, max)) yield entity;
+	}
+
+	get_entity_in_range(min: Vec2, max: Vec2) {
+		return maybe([...this.get_entities_in_range(min, max)][0]);
+	}
+
+	kill(entity_id: number) {
+		this.entities.delete(entity_id);
+	}
+}
+
+export class Engine {
+	world;
+
+	constructor(world: World) {
+		this.world = world;
+	}
+
+	async start() {
+		log("Started engine.");
+	}
+
+	add_session(client: ClientInterface) {
+		const player_entity = this.world.spawn_entity("`/", new Vec2(0, 0));
+		const session = new Session(client, this.world, player_entity);
+		session.spin();
+	}
+}
+
+function* displacement_steps(position: Vec2, displacement: Vec2) {
+	let pos = position;
+	let left = displacement;
+	while (left.len() >= 1) {
+		if (left.x() >= 1) {
+			pos = pos.add(new Vec2(1, 0));
+			left = left.sub(new Vec2(1, 0));
+		}
+		if (left.x() <= -1) {
+			pos = pos.add(new Vec2(-1, 0));
+			left = left.sub(new Vec2(-1, 0));
+		}
+		if (left.y() >= 1) {
+			pos = pos.add(new Vec2(0, 1));
+			left = left.sub(new Vec2(0, 1));
+		}
+		if (left.y() <= -1) {
+			pos = pos.add(new Vec2(0, -1));
+			left = left.sub(new Vec2(0, -1));
+		}
+		yield pos;
+	}
+}
+
+Deno.test("test_displacement", () => {
+	assertEquals(
+		[...displacement_steps(new Vec2(1, 1), new Vec2(4, 6))],
+		[new Vec2(2, 2), new Vec2(3, 3), new Vec2(4, 4), new Vec2(5, 5), new Vec2(5, 6), new Vec2(5, 7)],
+	);
+});