FX Driver
FX Driver actions map a changing gameplay value to visual effect properties.
Use them to make effects react in real time without custom scripting.
Core Concept
Each driver takes:
- Input
- Input Min
- Input Max
The value is normalized to 0-1, then used to control effect intensity.
Examples of valid inputs:
- Speed
- Thrust
- Heat
- Health
- Timer
- Proximity
Why Use Drivers
- Fast setup in the Action Editor
- Easy tuning by designers/artists
- Reusable across multiple effects
- Works well with pooled and runtime-spawned FX
Available Drivers
FxDriverTrailRenderer
Drives trail width, length, emission, gradient, and bloom intensity.
FxDriverLight
Drives light intensity and optional color gradient.
FxDriverParticleSystem
Drives emission rate and start size.
Typical Workflow
- Pick a gameplay value (for example thrust or speed).
- Assign it to Input.
- Set Input Min/Max to the expected gameplay range.
- Tune visual response until it feels right.
Practical Tips
- Keep gradients simple; use intensity for most punch.
- Reuse one input across multiple drivers for cohesive effects.
- Start with wide input ranges, then narrow as you tune.
Example
A single Thrust value can drive:
- Trail width
- Engine light intensity/color
- Particle emission
This creates a coordinated effect stack from one gameplay signal.