This is the ninth of a series of articles that cover my journey learning and exploring one of the most powerful indie game creation tools available - Unity. I’ll be sharing my knowledge and discoveries over a 12 week period. Each week I’ll post primarily on the process of learning Unity 3D along with other topics such as the history of the game engine, the community, and prominent artists/creators. Last week I covered lighting and baked lighting in Unity.
Unity’s Particle System
No game would be complete without effects. You need fire, water, and wind along with steam, smoke and electrical effects. And these are just the effects I can think of off the top of my head. How do you create these kinds of effects? By using Unity’s particle system which, like Lighting, is really great.
If you remember the basic elements of Unity creation you have the game object and the component(s) inside of the game object. What this means is that you can add a particle system (wind, flames, etc) to ANY object in Unity. The feature gives you an incredible amount of freedom to create unique effects.
The Unity manual has a great definition of a particle system:
Particles are small, simple images or meshes that are displayed and moved in great numbers by a particle system. Each particle represents a small portion of a fluid or amorphous entity and the effect of all the particles together creates the impression of the complete entity. Using a smoke cloud as an example, each particle would have a small smoke texture resembling a tiny cloud in its own right. When many of these mini-clouds are arranged together in an area of the scene, the overall effect is of a larger, volume-filling cloud.
Elements of a Particle System
Although it’s easy to set up a particle system in a scene (you simply add the component to whatever game object you are working with) it starts to become more complex when you have to figure in the elements of whatever system you are working with. Some of the particle elements are the lifetime of the particle, the emission rate, the size and spread of the particles and many more. Adjusting these elements against each other is what eventually determines the success of your effect.
Varying properties over time
Many of the numeric properties of particles or even the whole Particle System can vary over time. Unity provides several different methods of specifying how this variation happens:
- Constant: The property’s value is fixed throughout its lifetime.
- Curve: The value is specified by a curve/graph.
- Random Between Two Constants: Two constant values define the upper and lower bounds for the value; the actual value varies randomly over time between those bounds.
- Random Between Two Curves: Two curves define the upper and lower bounds of the value at a given point in its lifetime; the current value varies randomly between those bounds.
Particle Mega Video
Rather than go into written detail on the particle system, I’m sharing an excellent introduction to particles in Unity by Brackeys. This simple 10-minute tutorial will tell you everything you need to know about what you can do with Unity’s particle system. I also recommend Unity’s own tutorial on particles which you can find here.