Boids VFX · Lite · Fish Schools

Add swimming fish schools to aquariums, rivers, lakes and underwater environments with Boids VFX Lite — a free, focused edition of the GPU-driven Boids VFX system for Unity.

Not every scene needs advanced swarm navigation or complex interactions. Sometimes, a school of fish moving through a defined habitat is enough to make an environment feel more alive. Start with the included fish, then adapt their appearance and behaviour to your scene.

FOCUSED ON FISH. READY TO CUSTOMIZE.
- GPU-Driven Fish Schooling
- Procedural Fish Body Animation
- Lit & Unlit Fish Effects
- Custom Fish Meshes & Textures
- Box, Sphere, Capsule & Cylinder Habitats
- Obstacle Avoidance with Primitive Zones
- 11 Behaviour Presets
- Lifetime & Population Monitoring
- Edit Mode Preview
- Swarm Control Center & Runtime API

PDF and Markdown documentation are included in the package.

GIVE YOUR FISH THEIR OWN MOVEMENT STYLE

Create tightly grouped schools, loose groups or more independent movement using adjustable Cohesion, Alignment, Separation and Wander forces.

Fine-tune swimming speed, steering response and individual speed variation. Start with 11 included behaviour presets, then save your own movement settings for reuse.

Movement settings are independent of appearance, so the same fish effect can produce different schooling styles.

DEFINE A HABITAT AND ADD OBSTACLES

Use a single primitive Volume to define where your fish live. The entire population spawns immediately inside the habitat, while boundary settings control how fish turn near its edges and return after leaving it.

Add Obstacle Zones to steer fish around defined primitive shapes. Adjust clearance, detection distance and avoidance response to suit the size of your fish and the available swimming space.

Use this setup for aquariums, local underwater habitats and ambient fish populations.

MAKE THE SCHOOL FIT YOUR VISUAL STYLE

Use the included fish or assign your own compatible fish mesh and textures.

Choose Lit rendering for lighting and surface-map controls, or Unlit rendering for an unlit textured appearance. Adjust size, colour, individual scale variation and procedural body bending on the linked Visual Effect.

Custom fish require suitable geometry, orientation and a red vertex-colour animation mask. Mesh preparation is covered in the documentation.

CONFIGURE AND PREVIEW IN THE EDITOR

Swarm Control Center · Lite Edition brings references, movement, habitat settings, obstacles, population and presets into one Editor window.

Use the VFX Setup Assistant to check project requirements and access the demo. Preview movement directly in Edit Mode, without entering Play Mode.

Standard setup uses the provided components and Editor controls, with no custom movement scripts required. Optional Lifetime settings let fish die from age, while population monitoring reports how many remain alive.

For scripted integration, the Runtime API provides playback control, parameter changes, smooth transitions and a population-completion event.

CHOOSE LITE OR FULL FOR YOUR SCENE

Boids VFX Lite is a free, standalone edition with a focused feature set. It has no trial timer.
If you need fish swimming inside a simple habitat with configurable behaviour and obstacle avoidance, Lite may be all you need.

The full Boids VFX expands this foundation with birds and insects, Composite Volumes, Spawn Points, Follow and Spline Navigation, additional influence zones (Attraction, Repulsion and Flow), Death Zones, Trigger Zones and secondary VFX.

Explore Full when your project needs more advanced spawning, navigation and environmental interactions.

Boids VFX — Full Edition:
View the Full Edition on Unity Asset Store

See the Lite vs Full comparison image in the gallery for a detailed feature breakdown.

REQUIREMENTS
- Unity 6 or newer; tested with Unity 6000.0.77f1.
- Universal Render Pipeline (URP).
- Unity Visual Effect Graph package.
- GPU Compute Shader support on the target platform and graphics API.

KNOWN CONSTRAINTS & DESIGN TRADE-OFFS
- A single SwarmSystem supports up to 1,000 boids. Performance depends on population, mesh complexity, obstacles and rendering settings. Test your configuration on target hardware.
- Boids are GPU-simulated particles, not individual GameObjects with Transforms, Animators or Rigidbodies.
- Navigation uses local steering and primitive obstacles, not NavMesh pathfinding or exact MeshCollider collision. Tight or complex geometry may require adjustments.
- Fish animation uses shader deformation with suitable mesh geometry and Vertex Color.R masks. It does not run skeletal animation for individual fish.
- Dead boids do not automatically respawn. Reinitialize or restart the population to begin another cycle.
- Stop clears the population immediately. Pausing while preserving the simulation state is not supported.
- Main VFX particles have a technical lifetime of 9,999 seconds of VFX time. Rendering may end while the GPU simulation continues. Longer-running effects require starting a new simulation cycle.

Further configuration details, API examples and performance considerations are covered in the documentation.