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Phaser: collisions and screen boundaries

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This post is part of a Phaser series. Click here to see the first post of the series.

You can detect a collision between physics-enabled items.

Phaser offers us 2 handy methods, to start with.

We have collider and overlap. Both let us detect when objects get one near the other, but with a difference: collider automatically makes object bounce when they meet. overlap lets objects overlap with each other.

This is how we add a collider:

const collisionHappened = (dog, cat) => {

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

and this is how we add an overlap:

const overlapHappened = (dog, cat) => {

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

You can also set screen boundaries so physics objects will not disappear when they reach the end of the screen.

Call the setCollideWorldBounds() on the object, and pass it the true value:

const dog = this.physics.add.sprite(20, 20, 'dog')

If you also want it to bounce when it reaches the screen limit, call


The number you pass will determine how fast it will bounce back. Try setting 0.5 or 1.5 and you’ll see it bouncing with less or more energy.

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