a5c-ai/unity-vfx-graph

Unity VFX Graph Skill

Visual Effect Graph development for GPU-accelerated particle systems in Unity.

Overview

This skill provides capabilities for creating high-performance visual effects using Unity's Visual Effect Graph, leveraging GPU compute for millions of particles.

Capabilities

Particle Systems

• Create GPU particle systems
• Configure spawn, initialize, update, output contexts
• Handle particle attributes
• Implement particle collision

Procedural Effects

• Use noise and turbulence
• Implement SDF-based effects
• Create mesh sampling effects
• Build camera-based interactions

Visual Authoring

• Design effects in VFX Graph editor
• Create subgraphs for reuse
• Implement property sheets
• Build event-driven effects

Integration

• Connect to C# scripts
• Handle events and parameters
• Integrate with Timeline
• Manage performance budgets

Prerequisites

• Unity 2021.3+ with VFX Graph package
• SRP (URP or HDRP) project
• Compute shader capable hardware

Usage Patterns

Spawning Particles from Code

public class VFXController : MonoBehaviour
{
    [SerializeField] private VisualEffect vfx;

    void Start()
    {
        // Set properties
        vfx.SetFloat("SpawnRate", 100f);
        vfx.SetVector3("EmitterPosition", transform.position);
    }

    public void TriggerBurst()
    {
        // Send event
        vfx.SendEvent("OnBurst");
    }
}

Property Binding

// Expose VFX properties via C# bindings
vfx.SetInt("ParticleCount", 1000);
vfx.SetGradient("ColorOverLife", gradient);
vfx.SetTexture("ParticleTexture", texture);

Best Practices

1. Use subgraphs for reusable components
2. Profile GPU performance
3. Set particle count limits
4. Use LOD for distant effects
5. Optimize texture sampling

References

• VFX Graph Documentation