Harnessing SpriteKit's particle system

SpriteKit includes a powerful particle system that makes it easy to add exciting graphics to your game. Particle emitter nodes create many small instances of an image that are combined together to create a great-looking effect. You can use emitter nodes to generate snow, fire, sparks, explosions, magic, and other useful effects that would otherwise require a lot of effort.

For our game, you will learn how to use an emitter node to create a trail of small dots behind Pierre Penguin as he flies, making it easier for the player to learn how their taps influence Pierre's flight path.

When we are finished, Pierre's dot trail will look something like this:

Adding the circle particle asset

Each particle system emits multiple versions of a single image in order to create a cumulative particle effect. In our case, the image is a simple circle. To add the circle image to the game, follow these steps:

1. Open the Assets.xcassets file in Xcode.

2. Locate the [e-mail] and...