Implementing a particle system effect
A particle system is a system that controls particles. In our case, ParticleSystem is a class we will write that will spawn instances (lots of instances) of the Particle class (also a class we will write) that will create a simple explosion-like effect.
Here is an image of some particles controlled by a particle system:
Figure 22.1 – Particle system effect
Just for clarification, each of the colored squares is an instance of the Particle class and all the Particle instances are controlled and held by the ParticleSystem class. In addition, the user will create multiple (hundreds) of ParticleSystem instances by drawing with their finger. The particles will appear as dots or blocks until the user taps the pause button, when they will come to life. We will examine the code closely enough that you will be able to set, in code, the size, color, speed, and quantity of Particle and ParticleSystem instances.
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