修改

Question

我正在制作一个太空入侵者游戏，我似乎偶然发现了这个问题并且无法解决它。但有一件事我注意到，当我多次拍摄老板时会出现问题。帮助将是非常好的。

第351行

问题。

此场景为您提供了正确的外观：

Here是JSBIN格式

以下是代码：

var game = new Phaser.Game(500, 550, Phaser.CANVAS, 'gameDiv');

var CountDown = {

    preload: function() {


    },
    update: function() {

    },
    render: function() {


    }
}
var player;
var enemy;
var bullets;
var shields;
var enemies;
var greenEnemies;
var enemyBullet;
var bossLaunched = false;
var blueEnemiesBullets;
var bossEnemiesBullets;
var bossHealth = 50000;
var explosions;
var score = 0;
var scoreText;
var bulletTimer = 0;
var blueEnemies;
var mainState = {

        preload: function() {
            game.load.image('background', 'http://s1.postimg.org/nqynk9tkv/starfield.png')
            game.load.image('player', 'http://s28.postimg.org/9qdf4xrfx/145103252914234.gif')
            game.load.image('bullet', 'http://s9.postimg.org/z2bptetxn/bullet.png');
            game.load.image('green', 'http://s28.postimg.org/kpmq4byt5/enemy_green.png')
            game.load.spritesheet('explosionAnim', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/explode.png', 128, 128)
            game.load.bitmapFont('spacefont', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/spacefont/spacefont.png', 'https://rawgit.com/jschomay/phaser-demo-game/master/assets/spacefont/spacefont.xml');
            game.load.image('blue', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/enemy-blue.png')
            game.load.image('blueEnemyBullet', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/enemy-blue-bullet.png');
            game.load.image('boss', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/boss.png');
            game.load.image('deathRay', 'https://raw.githubusercontent.com/jschomay/phaser-demo-game/master/assets/death-ray.png');
        },

        create: function() {
            this.backgroundImg = this.game.add.tileSprite(0, 0, 500, 550, 'background')
            player = game.add.sprite(game.world.centerX, 500, 'player')
            player.health = 100;
            player.anchor.setTo(0.5)
            player.scale.setTo(0.25)
            game.physics.arcade.enable(player);
            game.physics.enable(player, Phaser.Physics.ARCADE);
            player.body.collideWorldBounds = true;
            this.game.inputEnabled = true;
            this.game.input.useHandCursor = true;
            player.body.maxVelocity.setTo(400, 400)
            player.body.drag.setTo(400, 400)

            //  The baddies!
            greenEnemies = game.add.group();
            greenEnemies.enableBody = true;
            greenEnemies.physicsBodyType = Phaser.Physics.ARCADE;
            greenEnemies.createMultiple(5, 'green');
            greenEnemies.setAll('anchor.x', 0.5);
            greenEnemies.setAll('anchor.y', 0.5);
            greenEnemies.setAll('scale.x', 0.5);
            greenEnemies.setAll('scale.y', 0.5);
            greenEnemies.setAll('angle', 180);
            greenEnemies.setAll('outOfBoundsKill', true);
            greenEnemies.setAll('checkWorldBounds', true);
            greenEnemies.forEach(function(enemy) {
                enemy.body.setSize(enemy.width * 3 / 4, enemy.height * 3 / 4);
                enemy.damageAmount = 20;
            })

            blueEnemies = game.add.group();
            blueEnemies.enableBody = true;
            blueEnemies.physicsBodyType = Phaser.Physics.ARCADE;
            blueEnemies.createMultiple(30, 'blue');
            blueEnemies.setAll('anchor.x', 0.5);
            blueEnemies.setAll('anchor.y', 0.5);
            blueEnemies.setAll('scale.x', 0.5);
            blueEnemies.setAll('scale.y', 0.5);
            blueEnemies.setAll('angle', 180);
            blueEnemies.forEach(function(enemy) {
                enemy.damageAmount = 40;
            });

            boss = game.add.sprite(160, -110, 'boss');
            boss.exists = true;
            boss.alive = false;
            boss.move = false;
            boss.anchor.setTo(0.5, 0.5);
            boss.damageAmount = 50;
            boss.angle = 180;
            boss.scale.x = 0.6;
            boss.scale.y = 0.6;
            game.physics.enable(boss, Phaser.Physics.ARCADE);
            boss.body.maxVelocity.setTo(100, 80);
            boss.dying = false;



                    //  Shields stat
                    shields = game.add.bitmapText(game.world.width - 250, 10, 'spacefont', '' + player.health + '%', 40);
                    shields.render = function() {
                        shields.text = 'Shields: ' + Math.max(player.health, 0) + '%';
                    };
                    shields.render();


                    //  Score
                    scoreText = game.add.bitmapText(10, 10, 'spacefont', '', 40);
                    scoreText.render = function() {
                        scoreText.text = 'Score: ' + score;
                        if (score == 100) {
                            console.log("OK")
                        }
                    };
                    scoreText.render();




                    this.launchGreenEnemy();

                    bullets = game.add.group();
                    bullets.enableBody = true;
                    bullets.physicsBodyType = Phaser.Physics.ARCADE;
                    bullets.createMultiple(30, 'bullet');
                    bullets.setAll('anchor.x', 0.5);
                    bullets.setAll('anchor.y', 1);
                    bullets.setAll('outOfBoundsKill', true);
                    bullets.setAll('checkWorldBounds', true);

                    //  Blue enemy's bullets
                    blueEnemiesBullets = game.add.group();
                    blueEnemiesBullets.enableBody = true;
                    blueEnemiesBullets.physicsBodyType = Phaser.Physics.ARCADE;
                    blueEnemiesBullets.createMultiple(30, 'blueEnemyBullet');
                    blueEnemiesBullets.callAll('crop', null, {
                        x: 90,
                        y: 0,
                        width: 90,
                        height: 70
                    });
                    blueEnemiesBullets.setAll('alpha', 0.9);
                    blueEnemiesBullets.setAll('anchor.x', 0.5);
                    blueEnemiesBullets.setAll('anchor.y', 0.5);
                    blueEnemiesBullets.setAll('outOfBoundsKill', true);
                    blueEnemiesBullets.setAll('checkWorldBounds', true);
                    blueEnemiesBullets.forEach(function(enemy) {
                        enemy.body.setSize(20, 20);
                    });


                      bossEnemiesBullets = game.add.group();
                    bossEnemiesBullets.enableBody = true;
                    bossEnemiesBullets.physicsBodyType = Phaser.Physics.ARCADE;
                    bossEnemiesBullets.createMultiple(30, 'blueEnemyBullet');
                    bossEnemiesBullets.callAll('crop', null, {
                        x: 90,
                        y: 0,
                        width: 90,
                        height: 90
                    });
                    bossEnemiesBullets.setAll('alpha', 0.9);
                    bossEnemiesBullets.setAll('anchor.x', 0.5);
                    bossEnemiesBullets.setAll('anchor.y', 0.5);
                    bossEnemiesBullets.scale.set(2, 2);
                    bossEnemiesBullets.setAll('outOfBoundsKill', true);
                    bossEnemiesBullets.setAll('checkWorldBounds', true);
                    bossEnemiesBullets.forEach(function(enemy) {
                        enemy.body.setSize(20, 20);
                    });

                    explosions = game.add.group();
                    explosions.enableBody = true;
                    explosions.physicsBodyType = Phaser.Physics.ARCADE;
                    explosions.createMultiple(30, 'explosionAnim');
                    explosions.setAll('anchor.x', 0.5);
                    explosions.setAll('anchor.y', 0.5);
                    explosions.forEach(function(explosion) {
                        explosion.animations.add('explosionAnim');
                    });
/*
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);
                    game.time.events.add(game.rnd.integerInRange(12000, 15000), this.launchBlueEnemy, this);*/



                    this.cursors = game.input.keyboard.createCursorKeys();
                    this.fireButton = game.input.keyboard.addKey(Phaser.Keyboard.SPACEBAR)



        },


                update: function() {
                     if(boss.move){

                        boss.exists = true;
                        if(boss.body.y>40){
                            boss.body.y=40;

                            game.add.tween(boss).to( { angle: 170 }, 700, Phaser.Easing.Linear.None, true);
                            game.time.events.add(game.rnd.integerInRange(1000, 2500), this.launchBossEnemy, this);
                        }
                        else{
                        boss.body.y++;
                        }
                      }

                    this.backgroundImg.tilePosition.y += 2;
                    player.body.acceleration.x = 0;
                    if (this.cursors.left.isDown) {
                        player.body.acceleration.x -= 600;

                    } else if (this.cursors.right.isDown) {
                        player.body.acceleration.x += 600;

                    }
                    game.physics.arcade.overlap(player, greenEnemies, this.shipCollideGreen, null, this);
                    game.physics.arcade.overlap(greenEnemies, bullets, this.bulletCollideGreen, null, this);

                    game.physics.arcade.overlap(player, blueEnemies, this.shipCollideBlue, null, this);
                    game.physics.arcade.overlap(blueEnemies, bullets, this.bulletCollideBlue, null, this);
                    game.physics.arcade.overlap(blueEnemiesBullets, player, this.enemyHitsPlayer, null, this)

                    game.physics.arcade.overlap(boss, bullets, this.bulletCollideBoss, null, this);
                    game.physics.arcade.overlap(blueEnemiesBullets, player, this.enemyHitsPlayer, null, this)

                    if (player.alive && this.fireButton.isDown) {
                        //Grab first bullet from the pool

                        if (game.time.now > bulletTimer) {
                            var bullet = bullets.getFirstExists(false);
                            if (bullet) {
                                bullet.reset(player.x, player.y + 8);
                                //Getting it up
                                bullet.body.velocity.y = -400;
                                bulletTimer = game.time.now + 250;
                            }

                        }
                    }

                    if (player.health <= 0) {
                        player.kill();
                    }
                    if (!(player.alive)) {
                       //GameOver
                    }



                },
                launchGreenEnemy: function() {

                    enemy = greenEnemies.getFirstExists(false);
                    if (enemy) {
                        enemy.reset(game.rnd.integerInRange(0, game.width), -20);
                        enemy.body.velocity.x = game.rnd.integerInRange(-300, 300);
                        enemy.body.velocity.y = 300;
                        enemy.body.drag.x = 100;
                        if (this.y > game.height) {
                            this.kill()
                        }

                    }


                    game.time.events.add(game.rnd.integerInRange(100, 3000), this.launchGreenEnemy, this);

                },

                shipCollideBlue: function(player, enemy) {

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(enemy.body.x + enemy.body.halfWidth, enemy.body.y + enemy.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    enemy.kill();
                    player.health = player.health - 40;
                    shields.render();

                },
                shipCollideGreen: function(player, enemy) {

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(enemy.body.x + enemy.body.halfWidth, enemy.body.y + enemy.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    enemy.kill();
                    console.log(player.health);

                    if (!bossLaunched && score > 0) {
                    //  dramatic pause before boss
                    boss.move=true;
                    game.time.events.add(2000, this.launchedBoss,this);
                }
                    player.health = player.health - 20;
                    shields.render();

                },

                launchedBoss:function(){
                     bossLaunched = true;
                     boss.move = true;


                },
                bulletCollideGreen: function(bullet, enemy) {

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    enemy.kill();
                    bullet.kill();
                    score += 20 * 10;
                    scoreText.render()
                },
                bulletCollideBlue: function(bullet, enemy) {

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    enemy.kill();
                    bullet.kill();
                    score += 40 * 10;
                    scoreText.render()
                },

                bulletCollideBoss :function(bullet,enemy){

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    bullet.kill();
                    console.log(bossHealth);
                    bossHealth -= 50;

                  /*  if(boss.health<=0){
                        console.log("boss DEAD");
                        boss.kill()
                    }*/
                    scoreText.render()
                },


                 launchBossEnemy: function() {

                    var bulletSpeed = 400;
                    var firingDelay = 2000;

                    var bank;

                    var enemy = boss
                    if (enemy) {


                        enemy.reset(160, 140);


                        var bulletSpeed = 400;
                        var firingDelay = 2000;

                        enemy.bullets = 1;
                        enemy.lastShot = 0;
                        enemy.update = function() {

                            enemyBullet = bossEnemiesBullets.getFirstExists(false);
                            for (i = 0; i <= 8; i++) {
                                if (enemyBullet &&
                                    this.alive &&
                                    this.bullets &&
                                    this.y > game.width / 8 &&
                                    game.time.now > firingDelay + this.lastShot) {
                                    this.lastShot = game.time.now;
                                    this.bullets--;
                                    enemyBullet.reset(this.x, this.y + this.height / 2);
                                    var angle = game.physics.arcade.moveToObject(enemyBullet, player, bulletSpeed);
                                    enemyBullet.damageAmount = this.damageAmount;
                                    enemyBullet.angle = game.math.radToDeg(angle);
                                }

                                //  Kill enemies once they go off screen
                                if (this.y > game.height + 200) {
                                    this.kill();
                                    this.y = -20;
                                }
                            }
                        }
                        game.time.events.add(game.rnd.integerInRange(8000, 8500), this.launchBlueEnemy, this);

                    }





                },
                launchBlueEnemy: function() {


                    var bulletSpeed = 400;
                    var firingDelay = 2000;

                    var bank;

                    var enemy = blueEnemies.getFirstExists(false);
                    if (enemy) {


                        enemy.reset(game.rnd.integerInRange(0, game.width), -20);
                        enemy.body.velocity.x = 200
                        enemy.body.velocity.y = 200;
                        enemy.body.drag.x = 100;

                        var bulletSpeed = 400;
                        var firingDelay = 2000;

                        enemy.bullets = 1;
                        enemy.lastShot = 0;
                        enemy.update = function() {

                            enemyBullet = blueEnemiesBullets.getFirstExists(false);
                            for (i = 0; i <= 3; i++) {
                                if (enemyBullet &&
                                    this.alive &&
                                    this.bullets &&
                                    this.y > game.width / 8 &&
                                    game.time.now > firingDelay + this.lastShot) {
                                    this.lastShot = game.time.now;
                                    this.bullets--;
                                    enemyBullet.reset(this.x, this.y + this.height / 2);
                                    var angle = game.physics.arcade.moveToObject(enemyBullet, player, bulletSpeed);
                                    enemyBullet.damageAmount = this.damageAmount;
                                    enemyBullet.angle = game.math.radToDeg(angle);
                                }

                                //  Kill enemies once they go off screen
                                if (this.y > game.height + 200) {
                                    this.kill();
                                    this.y = -20;
                                }
                            }
                        }
                        game.time.events.add(game.rnd.integerInRange(8000, 8500), this.launchBlueEnemy, this);

                    }





                },

                enemyHitsPlayer: function(player, bullet) {


                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    player.health -= 40
                    shields.render()


                    bullet.kill();
                },


                // Restart the game
                platformsCreate: function() {

                }
        };

        var Menu = {
            preload: function() {

            },
            create: function() {

            },
            update: function() {


            },
            render: function() {

            },
            start: function() {

            }

        };

        var Game_Over = {

            preload: function() {



            },
            create: function() {




            },
            update: function() {

            },
            render: function() {

            },
        };
        // Add and start the 'main' state to start the game
        game.state.add('CountDown', CountDown)
        game.state.add('main', mainState);
        game.state.add('Menu', Menu);
        game.state.add('Game_Over', Game_Over);
        game.state.start('main');

修改

更改了上面这行代码：

 bulletCollideBoss :function(bullet,enemy){

                    var explosion = explosions.getFirstExists(false);
                    explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    bullet.kill();
                    console.log(bossHealth);
                    bossHealth -= 50;

                  /*  if(boss.health<=0){
                        console.log("boss DEAD");
                        boss.kill()
                    }*/
                    scoreText.render()
                },

对此：

  bulletCollideBoss :function(bullet,enemy){

                    var explosion = explosions.getFirstExists(false);
                    if(explosion){
                        explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                    }

                    explosion.body.velocity.y = enemy.body.velocity.y;
                    explosion.alpha = 0.7;
                    explosion.play('explosionAnim', 30, false, true);
                    bullet.kill();
                    console.log(bossHealth);
                    bossHealth -= 50;

                  /*  if(boss.health<=0){
                        console.log("boss DEAD");
                        boss.kill()
                    }*/
                    scoreText.render()
                },

我得到错误：未捕获的TypeError：无法读取null的属性'body'在第355行。

这是图片：

这个工作

bulletCollideBoss :function(bullet,enemy){


                var explosion = explosions.getFirstExists(false);
                if(explosion){
                   explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                   explosion.body.velocity.y = enemy.body.velocity.y;
                   explosion.alpha = 0.7;
                   explosion.play('explosionAnim', 30, false, true);
                }

                bullet.kill();
                console.log(bossHealth);
                bossHealth -= 50;

              /*  if(boss.health<=0){
                    console.log("boss DEAD");
                    boss.kill()
                }*/
                scoreText.render()
            },

Answer 1

只需在代码中的其他位置执行该行之前的空检查：

if (explosion) {                 
     explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
     explosion.body.velocity.y = enemy.body.velocity.y;
     explosion.alpha = 0.7;
     explosion.play('explosionAnim', 30, false, true);
}

Answer 2

你可能想要改变它：

 bulletCollideBoss :function(bullet,enemy){

                var explosion = explosions.getFirstExists(false);
                if(explosion){
                   explosion.reset(bullet.body.x + bullet.body.halfWidth, bullet.body.y + bullet.body.halfHeight);
                   explosion.body.velocity.y = enemy.body.velocity.y;
                   explosion.alpha = 0.7;
                   explosion.play('explosionAnim', 30, false, true);
                }

                bullet.kill();
                console.log(bossHealth);
                bossHealth -= 50;

              /*  if(boss.health<=0){
                    console.log("boss DEAD");
                    boss.kill()
                }*/
                scoreText.render()
            },

Answer 3

解：

为爆炸池制造90次爆炸

explosions.createMultiple(90, 'explosionAnim');

TL; DR：

前几天我遇到了同样的问题。如果这个动画对你来说很重要，那么其他用户解决方案可能会产生副作用（对我而言）。

很容易修复和理解它。

见这一行：

var explosion = explosions.getFirstExists(false);

getFirstExists 会返回第一个孩子。 param 存在是 false 。

存在 param是什么？

如果是，请找到第一个现有的孩子;否则找到第一个不存在的孩子。（http://phaser.io/docs/2.4.4/Phaser.Group.html#getFirstExists）

但我有30次爆炸！

这就是重点！当你遇到这个错误时，所有爆炸都是可见的（'EXIST'）。

我需要多少爆炸？

请注意，您正在制作30次爆炸：

explosions.createMultiple(30, 'explosionAnim');

但是你要制造90发子弹（玩家+蓝色敌人+老板）：

bullets.createMultiple(30, 'bullet');
blueEnemiesBullets.createMultiple(30, 'blueEnemyBullet');
bossEnemiesBullets.createMultiple(30, 'blueEnemyBullet');

如果所有这些子弹同时爆炸，你将需要90次爆炸。

未捕获的TypeError：无法在Phaser中读取null的属性“reset”

修改

这个工作

3 个答案:

解：

TL; DR：