Phaser: Handling Collisions and Screen Boundaries

In this post, we will explore how to handle collisions between objects and set screen boundaries in Phaser.

Introduction

Phaser provides two methods that are useful for detecting collisions between physics-enabled items: collider and overlap. Both methods allow us to detect when objects come into proximity with each other, but with a slight difference in their behavior. The collider method automatically makes objects bounce when they collide, while the overlap method allows objects to overlap.

Handling Collisions

To add a collider between two objects, you can use the following code:

const collisionHappened = (dog, cat) => {
    projectile.destroy();
}

this.physics.add.collider(dogs, cats, collisionHappened, null, this);

And to add an overlap between two objects, you can use the following code:

const overlapHappened = (dog, cat) => {
    projectile.destroy();
}

this.physics.add.overlap(dogs, cats, collisionHappened, null, this);

Replace dogs and cats with the groups or arrays of objects you want to collide or overlap. The collisionHappened and overlapHappened functions are the callbacks that will be executed when a collision or overlap occurs.

Setting Screen Boundaries

In addition to handling collisions, you can also set screen boundaries for objects to prevent them from disappearing when they reach the edge of the screen. To do this, call the setCollideWorldBounds() method on the object and pass true as the value:

1 2	const dog = this.physics.add.sprite(20, 20, 'dog'); dog.setCollideWorldBounds(true);

If you want the object to bounce when it reaches the screen limit, you can call the setBounce() method on the object:

1	dog.setBounce(1);

The parameter you pass to setBounce() determines how fast the object will bounce back. You can try different values like 0.5 or 1.5 to adjust the energy of the bounce.

Conclusion

In this post, we explored how to handle collisions between objects using Phaser’s collider and overlap methods. We also learned how to set screen boundaries for objects to prevent them from disappearing. These techniques can be useful for creating dynamic and interactive games in Phaser.

Tags: Phaser, collisions, screen boundaries