Enemy 1초마다 등장 & 화면 바깥에서 랜덤하게 등장

src/scenes/PlayingScene.js

@@ -2,6 +2,7 @@ import Phaser from 'phaser';
 import Config from "../Config";
 import Player, { Direction } from '../characters/Player';
 import Enemy from '../characters/Enemy';
+import { getRandomPosition } from '../utils/math';
 
 export default class PlayingScene extends Phaser.Scene {
   constructor() {
@@ -34,6 +35,7 @@ export default class PlayingScene extends Phaser.Scene {
     // enemy
     this.m_enemies = this.physics.add.group();
     this.m_enemies.add(new Enemy(this, Config.width / 2 - 200, Config.height / 2 - 200, "bat", "bat_anim", 10));
+    this.addEnemy("bat", "bat_anim", 10);
 
     // collisions
     this.physics.add.overlap(this.m_attacks, this.m_enemies, (attack, enemy) => {
@@ -71,4 +73,15 @@ export default class PlayingScene extends Phaser.Scene {
       this.m_player.move(Direction.Down);
     }
   }
+
+  addEnemy(enemyTexture, enemyAnim, enemyHp) {
+    this.time.addEvent({
+      delay: 1000,
+      callback: () => {
+          let [x, y] = getRandomPosition(this.m_player.x, this.m_player.y);
+          this.m_enemies.add(new Enemy(this, x, y, enemyTexture, enemyAnim, enemyHp));
+      },
+      loop: true,
+    });
+  }
 }

src/utils/math.js

@@ -0,0 +1,14 @@
+import Config from "../Config";
+
+/**
+ * (x, y)로부터 r만큼 랜덤하게 떨어진(각도랜덤) 좌표 반환
+ * @param {Number} x
+ * @param {Number} y
+ */
+export function getRandomPosition(x, y) {
+    const randRad = Math.random() * Math.PI * 2;
+    const _r = Math.sqrt(Config.width*Config.width + Config.height*Config.height) / 2;
+    const _x = x + (_r * Math.cos(randRad));
+    const _y = y + (_r * Math.sin(randRad));
+    return [_x, _y];
+}