About Fluid Frenzy

Key Features Contents Requirements Limitations Pipeline Support Platform Support Feature Support

Installation

Package Manager Unity Package File

Samples

Importing Samples Universal Render Pipeline Running Samples River Grand Canyon Water Modifiers Volcano Terraform Fossil Finder Pool Simple Terraform Tiled Simulation Runtime Setup GPULOD Terrain Scene Configuration

Setup

Simulation Time Step Water Simulation Terraform Simulation Simulation Regions Fluid Channels Shader Stripper GPULOD Displacement Waves Flow Mapping Ocean FFT Cascades Sampling Universal Render Pipeline High-Definition Render Pipeline

Fluid Frenzy Toolbar

Accessing the Toolbar Modes Sculpt Mode (WIP) Modifier Mode Shared Settings Terrain or Fluid Layer Splat Channels Blend Mode Tool Properties

Fluid Simulation Components

Fluid Simulation Terrain and Obstacle Input Boundary Conditions Side Border Settings Domain Solver Initial Conditions Terrain & Ground Simulation Culling Extension Layers Create Collider Fluid Simulation Settings Creation Properties Second Layer Flux Fluid Simulation The Pipe (Flux) Model Simulation Characteristics Flux Fluid Simulation Settings Creation Specialized Flux Properties Flow Fluid Simulation The 2D Height Field Model Performance and Stability Solver Ocean FFT Coupling Flow Fluid Simulation Settings Creation Specialized Flow Properties Foam Layer Foam Layer Settings Foam Render Settings Foam Decay Settings Foam Pressure Settings Foam Wave Settings Shallow Foam Settings Turbulence Foam Settings Fluid Flow Mapping Fluid Flow Mapping Settings Erosion Layer Multi-Layer Terrain System Terrain Modification Processes Erosion Settings Terraform Layer Liquefaction (Solid Terrain to Fluid) Fluid Contact Reactions (Fluid and Terrain) Fluid Mixing (Fluid + Fluid to Solid Terrain) Fluid Contact Reaction Terraform Settings Terrain Modifier Terrain Modifier Settings Terraform Modifier Fluid Particle Generator Splash Particles Surface Particles Fluid Particle System Fluid RigidBody Prerequisite Fluid Density Calibration Interaction Calculation Fluid Displacement Profile Fluid Interaction Profile Fluid RigidBody Lite Fluid Simulation Obstacle Settings Fluid Event Trigger

Fluid Rendering Components

Fluid Renderer Fluid World Renderer Fluid Renderer vs Fluid World Renderer Setting up a tiled world Which simulations are included General Mesh Rendering Detail Waves & Displacement Ocean FFT (cascaded) Water World Renderer Underwater Effects Caustics Surface Reflections Ocean FFT Settings Surface Renderer Render Properties Detail Wave Effect Detail Wave Settings HDRP Water Surface Properties Water Rendering Water Surface Water Shader Underwater Effect Underwater Settings Caustics Effect Caustics Settings Surface Reflections Lava Lava Surface Under Lava Effect Lava Shader Particles Shaders Shadows HDRP Water System

Fluid Modifiers

Fluid Modifier Volume Fluid Source Settings Fluid Flow Settings Fluid Force Settings Fluid Modifier Waves Fluid Modifier Pressure Foam Modifier

Terrain

Simple Terrain Terraform Terrain Terraform Terrain Shader Terraform Terrain (Single Layer) Shader

C# Interaction & Scripting

Fluid Simulation Manager Simulation control Adding fluid Applying flow and forces Sampling the simulation

Using ShaderGraph

Fluid Simulation Nodes Terraform Terrain Nodes Particle Nodes

Tiled Simulations

Purpose Setup Padding for Continuity

Physics Colliders

Surface Collider GPU-CPU Synchronization and Performance Collider Properties

Simulation Debugger

Third-party Support

Enviro 3 Sky and Weather COZY: Stylized Weather 3 Curved World

Future Updates & Roadmap

Fluid Frenzy: 2026 Development Roadmap Roadmap Overview Upcoming Feature Breakdown Old Roadmap

C# Interaction & Scripting

Fluid Frenzy exposes a static API on FluidFrenzy.FluidSimulationManager for querying and modifying all registered Fluid Simulation components in the scene. Each call iterates every active simulation and applies the operation where the world position falls inside that simulation’s bounds.

The manager is driven automatically by FluidSimulationLoop, which hooks into Unity’s player loop (FixedUpdate by default, or Update when FLUIDFRENZY_RUN_UPDATE is defined). You normally do not call Step yourself unless you are building a custom integration.

Fluid Simulation Manager

Simulation control

FluidSimulationManager.simulations          // List<FluidSimulation> of all registered sims
FluidSimulationManager.globalTimeScale      // float multiplier for all sim time (script-only)
FluidSimulationManager.Step(deltaTime, maxSteps)
FluidSimulationManager.MarkSettingsChanged(bool changed)
FluidSimulationManager.RequestObstacleUpdate(bool changed)

Step advances every registered simulation, runs solid-to-fluid coupling on Fluid RigidBody instances, and updates cull/pause state from active game cameras. MarkSettingsChanged and RequestObstacleUpdate broadcast to all simulations when shared settings or obstacle geometry change at runtime.

Adding fluid

AddFluid(Vector3 worldPos, Vector2 size, float amount, float falloff, int layer, float timestep)

Adds fluid in a circular region at the specified world position and size. layer selects the fluid layer index. falloff controls the radial gradient. timestep is the delta time for this application (typically Time.deltaTime).

Applying flow and forces

ApplyFlow(Vector3 worldPos, Vector2 direction, Vector2 size, float strength, float falloff, float timestep)
ApplyFlowVortex(Vector3 worldPos, Vector2 size, float innerStrength, float outerStrength, float timestep)
ApplyForce(Vector3 worldPos, Vector2 direction, Vector2 size, float strength, float falloff, float timestep, bool splash)
ApplyForceVortex(Vector3 worldPos, Vector2 size, float strength, float falloff, float timestep)
ApplyForce(Texture texture, float strength, float timestep)

These mirror Fluid Modifier Volume behaviors programmatically. Flow methods write to the velocity field; force methods displace the height field. Set splash to true on ApplyForce for an outward radial impulse instead of a directional push. The texture overload applies a red-channel height/force mask in simulation UV space.

Sampling the simulation

Height & velocity
bool GetHeight(Vector3 worldPos, out Vector2 heightData)
bool GetHeightLayer(Vector3 worldPos, out Vector2 heightData, out int layer)
bool GetHeightVelocity(Vector3 worldPos, out Vector2 heightData, out Vector3 velocity)

Samples height and/or velocity at the specified world space position when inside a simulation’s bounds.

  • heightData.x contains the total height in world space, including the height of the underlying terrain.
  • heightData.y contains depth of the fluid in relation to the underlying terrain.
  • velocity contains the fluid velocity in world space.
  • GetHeightLayer also returns the dominant (highest) fluid layer index at that point.

Returns false when no simulation contains the position or no valid data is available.

Normals
bool GetNormal(Vector3 worldPos, out Vector3 normal)

Samples the world-space surface normal at the specified position.

Distance field
bool GetNearestFluidLocation2D(Vector3 worldPos, out Vector3 fluidLocation)
bool GetNearestFluidLocation3D(Vector3 worldPos, out Vector3 fluidLocation)

Samples the fluid distance field to find the nearest location containing fluid.

  • 2D returns the nearest XZ location from the distance field; Y is copied from worldPos.y. Use this when you will sample other data at that horizontal location.
  • 3D returns the nearest location including the fluid surface height. Useful for placing audio sources or markers directly on the water line.
Example

This script places a GameObject containing an AudioSource at the nearest fluid location relative to the object. Attach it to a camera or player.

public class FluidFinder : MonoBehaviour
{
    public GameObject audioSource;

    void Update()
    {
        FluidFrenzy.FluidSimulationManager.GetNearestFluidLocation3D(transform.position, out Vector3 location);
        audioSource.transform.position = location;
    }
}