Dev Diary #4: Creating Stylized Explosion VFX in Unity!

Our VFX specialist wrote this blog on stylized explosions! You can read the full article and view the images he is referencing here:

Dev's take on stylized VFX in Unity

Creating Stylized Explosion VFX in Unity! Ryan Bradford

Welcome!

Stylized games have seen a massive surge to the forefront of the gaming industry, and it just so happens that I am working on one!

Ringleaders

In this post I will explain the way that I approach an effect like this, how you might apply some artistic principles to your own, and some general tips at the end for the unity particle system.

Here's a look at the explosion I'll be referencing throughout this post:

The Boom What is the most important part of the explosion? The BOOM! So, first things first, it is important to understand how you want your boom to appear. Looking at a conventional explosion we can break it up into a couple of sections:

The explosion is initiated This can be any sort of signal or implication that a blast is about to happen. In the example, a mine is placed and then begins activating. It is important to use this to telegraph to the player what is about to happen so they know to run! This section can be anything from a couple of particles being sucked into the center, to an entire pre-explosion animation sequence.

The Sun Phase If you look closely you can see that right at the start of the explosion there is the most intense color and heat.

This should be communicated through your initial particle burst. Typically this is made up of a bright flash followed by a ball of the brightest/most intense color you want present in the effect. It's important that the Sun Phase only lasts a moment* so that the rest of the explosion can play out. * -- This is how traditional explosions work, and by no means are you limited to keeping this short if your explosion should be slowed down or last longer than usual. The BOOM Now comes the blast! Here we get the typical smoke cloud and explosion of debris that you find in most grenade and bomb effects. I feel this is the best place for artistic expression because this phase typically lasts a second or two and is easily visible during run time. In a stylized effect, it can be fun to make up shapes that your smoke cloud takes on, create layering with multiple clouds, and use colors that typically aren't found in real life explosions. In the example above you can see we're using a noise texture on our expanding spheres of post Sun Phase smoke. Additionally we've layered multiple effects to create a shadow cloud that generates a lot of contrast with the larger red cloud. Some good options for play here can be to change the shape of your expanding mesh or try different color combinations (vibrating colors are a great place to start!). The Particles Now that we have covered the basic approach, it's time to discuss how to actually get there. The Unity particle system is pretty intricate, and I would highly recommend you take a look at it before continuing because particles can be tricky little goobers. Some other great resources are Gabriel Aguiar and VFX Apprentice.

One more thing before you go deeper, it would be wise to brush up on your photoshop skills at this point. The particles are where an understanding of 2D painting and technical know-how come together.