feat: implemented enemy horizontal moving

Author: bramcomyn

src/main.ts

@@ -12,6 +12,7 @@ const config: Phaser.Types.Core.GameConfig = {
     width: 800,
     height: 600,
     parent: "game-container",
+    pixelArt: true,
 
     scene: {
         preload: preload,
@@ -38,7 +39,7 @@ let playerState: PlayerStateMachine;
 let bulletState: BulletStateMachine;
 let enemyState: EnemyStateMachine;
 
-const game = new Phaser.Game(config);
+export const game = new Phaser.Game(config);
 
 function preload(this: Phaser.Scene) {
 

src/states/enemies.ts

@@ -1,17 +1,50 @@
-import { ENEMY_RELOAD_TIME_MS } from "../util/constants";
+import { ENEMY_RELOAD_TIME_MS, ENEMY_SHIFT_MOVES, ENEMY_SHIFT_OFFSET_X, ENEMY_SHIFT_TIME_MS } from "../util/constants";
 import { StateMachine } from "./state-machine";
 
 export class EnemyStateMachine implements StateMachine {
     constructor(
         private scene: Phaser.Scene,
         public enemies: Phaser.Physics.Arcade.Group,
-        private reloadTime: number = 0
+
+        private reloadTime: number = 0,
+        private shiftTime: number = ENEMY_SHIFT_TIME_MS,
+        private left: boolean = false,
+        private moves: number = ENEMY_SHIFT_MOVES,
     ) {}
 
     update(time: number, delta: number): void {
 
         this.refreshEnemies(delta);
+        this.shiftEnemies(delta)
+        
+    }
+
+    private shiftEnemies(delta: number) {
+
+        this.shiftTime -= delta;
+        if (this.shiftTime <= 0) {
+            this.switchSidesIfRequired();   
+            this.move();
+        }
+
+    }
+
+    private switchSidesIfRequired() {
 
+        if (this.moves === 0) {
+            this.left = !this.left;
+            this.moves = ENEMY_SHIFT_MOVES;
+        }
+
+    }
+
+    private move() {
+
+        const offset = this.left ? -ENEMY_SHIFT_OFFSET_X : ENEMY_SHIFT_OFFSET_X;
+        this.enemies.incX(offset);
+        this.moves--;
+        this.shiftTime = ENEMY_SHIFT_TIME_MS;
+
     }
 
     private refreshEnemies(delta: number) {
@@ -29,7 +62,7 @@ export class EnemyStateMachine implements StateMachine {
 
     private createEnemies() {
 
-        this.enemies.create(100, 300, "enemy");
+        this.enemies.create(600, 300, "enemy");
         this.enemies.create(700, 300, "enemy");
 
     }
@@ -39,11 +72,11 @@ export class EnemyStateMachine implements StateMachine {
         enemy: HandleBulletHitArgumentType
     ) {
 
-        bullet.destroy();
-        
         const enemySprite = enemy as Phaser.Physics.Arcade.Sprite;
-        // TODO: play destruction animation
+        
+        bullet.destroy();
         enemySprite.destroy();
+
     }
 
 }

src/states/player.ts

@@ -29,7 +29,7 @@ export class PlayerStateMachine implements StateMachine {
         private state: PlayerState = PlayerState.Idle
     ) {}
 
-    update(time: number, delta: number): void {
+    update(_time: number, _delta: number): void {
 
         const next = states[this.state].onUpdate(this.scene, this.player, this.cursors);
         if (next !== this.state) {
@@ -45,38 +45,38 @@ export class PlayerStateMachine implements StateMachine {
 const states: Record<PlayerState, StateHandlers> = {
 
     "idle": {
-        onEnter(scene, player) {
+        onEnter(_scene, player) {
             player.anims.stop();
             player.setVelocityX(0);
-        }, onUpdate(scene, player, cursors) {
+        }, onUpdate(_scene, _player, cursors) {
             if (cursors.left.isDown) return PlayerState.MoveLeft;
             if (cursors.right.isDown) return PlayerState.MoveRight;
             return PlayerState.Idle;
-        }, onExit(scene) {
+        }, onExit(_scene) {
 
         }
     },
 
     "move-left": {
-        onEnter(scene, player) {
+        onEnter(_scene, player) {
             player.anims.play("move-left");
             player.setVelocityX(-PLAYER_SPEED);
-        }, onUpdate(scene, player, cursors) {
+        }, onUpdate(_scene, _player, cursors) {
             if (!cursors.left.isDown) return PlayerState.Idle;
             return PlayerState.MoveLeft;
-        }, onExit(scene) {
+        }, onExit(_scene) {
 
         }
     },
 
     "move-right": {
-        onEnter(scene, player) {
+        onEnter(_scene, player) {
             player.anims.play("move-right");
             player.setVelocityX(PLAYER_SPEED);
-        }, onUpdate(scene, player, cursors) {
+        }, onUpdate(_scene, _player, cursors) {
             if (!cursors.right.isDown) return PlayerState.Idle;
             return PlayerState.MoveRight;
-        }, onExit(scene) {
+        }, onExit(_scene) {
 
         }
     }

src/util/constants.ts

@@ -6,3 +6,6 @@ export const BULLET_SPEED = -500;
 export const BULLET_DELAY_MS = 250;
 
 export const ENEMY_RELOAD_TIME_MS = 500;
+export const ENEMY_SHIFT_TIME_MS = 800;
+export const ENEMY_SHIFT_OFFSET_X = 10;
+export const ENEMY_SHIFT_MOVES = 7;