STANDARD
February 26, 2019
Fireball FX in Unity
Unity 5 – Game Effects VFX – Fireball Spell / Projectile
Gabriel Aguiar Prod.
They start by creating a basic fireball shape in Photoshop. They used the brush presets to get a nice, fuzzy and flowy effect for drawing this. I went with Round Watercolor since that seemed pretty close to what they used. They also turn the opacity down to allow for increased color on the overlapped sections.
In Photoshop I had something selected on a layer still so when I tried to draw it would only draw in that selection, so that took some time to figure out that issue. They like to use white and just color in Unity. I also used some black to hedge out some of the white values, but not sure if that will create issues in Unity later.
We started creating the Particle System in Unity. We begin by creating a new material that they suggest changing the shader to Particles/Additive, which is a legacy shader now. I tried Particles/Standard Surface, and set the Albedo map to our PNG file instead of dragging it into a texture box (what is done in Particles/Additive).
In the Particle System, we turned off Shape. We edited 3D start size with random between 2 constants. This lets you set bounds that it could scale on any axis. We changed Emission Rate over Time to 1.
We added Rotation over Lifetime. You turn on Separate Axes to get access to more axis options. You also need to change the Start Speed to 0 so it stays in place and solely rotates. You raise the emission rate now to have several spinning at once, and alter the opacity to get the desired visual.
We changed the Render Alignment to Local so it doesn’t always face the camera.
You need to find the balance between: Start Lifetime, Opacity, and Emission Rate over Time. For Colors you can use Start Color/Random Between 2 Constants, or Color over Lifetime. Color over Lifetime gives better options with a gradient functionality.
We added another particle system as a child to the original one. This used another Photoshop image as a texture that was just a small ball of light. This would be used in the material (another Particles/Standard Unlit) of the particle system, as well as for its trail.
This particle system used the following effects: Velocity over Lifetime, Color over Lifetime, Size over Lifetime, Noise, and Trails. The trails add a wind-like light trail effect to each particle that adds a lot to the system. The noise makes trails curvier and more random/organic looking as opposed to always firing in straight lines.
We then added a duplicated version of this secondary particle system but removed the noise and random velocities to just have it travel in a straight line directly behind the overall particle system. Finally we added a Light to the main particle system. This is done by creating a light prefab and dragging it into the Light section of the particle system.
SUMMARY
- Use white colors for FX for Unity so you can color them in Editor
- In Particle Systems, in Renderer, increase Max Particle Size (i.e. 3) so when you get closer you don’t get weird problems
- Adding Noise to the particle system can make it look more random and organic
- You can add Light prefabs to particle systems