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 World Runtime Setup State Sync GPULOD Terrain Scene Configuration

Setup

Simulation Time Step Water Simulation Terraform Simulation Layer Capture Simulation Baked Surface Playback 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 Simulation Preview Modes Sculpt Mode 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 Fluid Simulation Static Fluid Surface Bake Foam Layer Foam Layer Settings Foam Render Settings Foam Decay Settings Foam Pressure Settings Foam Wave Settings Shallow Foam Settings Turbulence Foam Settings Wetness Layer Wetness Layer Settings Rendering Settings Decay 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 Sediment Modifier Sediment 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 Floater Fluid Simulation Obstacle Settings Fluid Event Trigger Fluid Ripple Zone (Beta) Fluid Ripple Impulse (Beta)

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 Water World Renderer Ocean FFT Settings Surface Renderer Render Properties Detail Wave Effect Detail Wave Settings HDRP Water Surface Properties Water Rendering Water Surface Underwater Effect Underwater Settings Current Particles Current Particle Settings Wet Lens Effect Wet Lens Settings Caustics Effect Caustics Settings Surface Reflections Fluid Decal Renderer Lava Lava Surface Under Lava Effect Shadows HDRP Water System

Fluid Shaders

Water Shader Stylized Water Shader Toon Water Shader Lava Shader Particle Shaders Fluid Decal Shader

Terrain

Simple Terrain Eight-layer terrain Terrain sculpting and painting Brush stamps Sculpt tools Height layers and splat Scene View shortcuts Strength, undo, and preview Terraform Terrain Terraform Terrain Shader Terraform Terrain (Single Layer) Shader

Fluid Modifiers

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

C# Interaction & Scripting

Fluid Simulation Manager Simulation control Multiplayer hooks (Beta) Adding fluid Adding sediment Applying flow and forces Sampling the simulation Per-simulation brushes Creating simulations, modifiers, and obstacles Simulations Surfaces In-memory settings Extension layers Terraform terrain and simulation Editor presets Fluid modifiers Terrain and terraform brushes Obstacles

Using ShaderGraph

Fluid Simulation Nodes Terraform Terrain Nodes Particle Nodes Current Displacement Shaders

Tiled Simulations

Purpose Setup Padding for Continuity

Physics Colliders

Which collider to use Surface Collider GPU-CPU Synchronization and Performance Collider Properties

Simulation Debugger

Edit Mode Preview

AI Skills

How to use them

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

Fluid Frenzy Toolbar

The Fluid Frenzy Toolbar is a dedicated overlay for the Unity Scene View, designed to streamline fluid simulation, terrain, terraform, and obstacle modifier placement. It features a responsive UI that adapts to both horizontal and vertical layouts depending on your Scene View dimensions.

Accessing the Toolbar

To enable the toolbar in your Scene View, right-click on the Scene View tab (or the Overlay menu icon), navigate to Overlays, and select Fluid Frenzy > Level Design. (The overlay was previously listed as Fluid Frenzy > Toolbar.) This strip holds Sculpt Mode, Modifier Mode, and the shared layer and brush controls.

Simulation preview transport lives on a second overlay: Fluid Frenzy > Simulation Preview. You can enable both overlays on the same Scene View and dock them where you like. They are independent so preview controls do not crowd the sculpt UI.

Simulation Preview

The Simulation Preview overlay includes Play, Pause, Stop, and Reset for Edit Mode Preview. These controls match Window > Fluid Frenzy > Preview Simulation and the Preview button on the Fluid Simulation inspector. They are available while you use Sculpt Mode or Modifier Mode on Level Design. Stop preview before sculpting so the simulation is not using the live terrain textures.

Control Action
Play Starts the simulation in Edit Mode. If no simulations are enabled, every loaded simulation is started.
Pause Pauses the simulation. GPU resources stay allocated and the water stays frozen in place.
Stop Stops the simulation and releases GPU resources. Terraform and erosion terrain return to the maps stored in Terrain Data. Preview is session-only and is not saved with the scene.
Reset Resets the water on simulations that are currently previewing.

Preview is disabled while Unity is in Play Mode. The solver then runs from Play Mode as usual.

Modes

The toolbar is divided into two primary modes of operation. You can switch between them using the toggle buttons located at the start of the toolbar.

Sculpt Mode

Sculpt Mode paints heightmaps and splat layers directly onto Simple Terrain and Terraform Terrain in the Scene View. Your edits are saved with the scene in the Terrain Data asset. This is for building the level in the editor. Changes from the Erosion Layer or Terrain Modifier during Edit Mode Preview or Play Mode are separate.

The same brushes, tools, and sliders appear on the terrain inspector Paint tab. Changing Size on the toolbar updates the inspector immediately, and the reverse is true. Size and Strength slider ranges (min/max on the folded-out sliders on Paint) persist per project in ProjectSettings/Packages/com.frenzybyte.fluidfrenzy/LevelDesignSliders.asset. The active brush texture is remembered for the editor session (including after a domain reload).

When you can sculpt

  • Unity must be in Edit Mode (not Play Mode).
  • Edit Mode Preview must be stopped so the simulation is not owning the live heightmap.
  • Sculpt input is enabled when Level Design is visible, Sculpt Mode is on, or when a terrain is selected and the inspector Paint tab is open.

While you work, the Scene View shows a cursor preview of the brush footprint on the terrain. Press G to switch to live mesh preview, which deforms the terrain mesh to show the result of the brush before you click (helpful for Set, Min, Max, and cliff shapes). Press G again to return to the lighter cursor preview.

Choosing a brush

Click the brush thumbnail on the toolbar to open a popup grid of stamp textures. Pick any thumbnail to use it for the next strokes. The list matches the scrollable palette on the Paint tab. Package brushes are soft gaussian falloffs. You can add project folders under Scan Folders on Paint (see Brush stamps). Only the red channel of the texture is used as the brush shape. Rotate the stamp with Rot or Alt + scroll.

Button Tool Summary
+ Raise or Lower Add or subtract height on the selected layers. Hold Ctrl (Windows) or Cmd (macOS) while painting to lower.
Sm Smooth Average neighboring heights inside the brush.
Sh Sharpen Emphasize ridges and cliff edges. Adjust Shrp (feature sharpness).
= Set Height Blend toward a target height. Stamp black pixels are skipped.
< Minimum Pull height down where it is above the target (digging, shelves).
> Maximum Push height up where it is below the target (plateaus).
Sl Slippage Steep slopes on the selected layer only slide downhill and pile at the bottom. Adjust Ang (rest angle in degrees).
L / W Height space L = local layer thickness. W = world surface height (Set, Min, Max only).

Scene View shortcuts (sculpt)

Input Action
Left drag Paint a stroke (one undo group per stroke).
Ctrl / Cmd + drag Lower while + is selected.
Ctrl / Cmd + scroll Brush Size (diameter in world units).
Shift + scroll Brush Strength (Str, 0–100).
Alt + scroll Brush Rotation (Rot).
G Toggle live mesh preview vs cursor preview.
Alt + drag Does not paint (Alt is used for rotation via scroll).

For full tool descriptions, layers, splat painting, and custom brushes, see Terrain sculpting and painting.

Modifier Mode

This mode provides a drag-and-drop palette for placing simulation and layout objects. To use these tools, simply click and drag an icon from the toolbar directly into the Scene View to spawn the object at that location.

Icon Component
Fluid Source
Fluid Force
Fluid Current
Fluid Path
Fluid Vortex
Terrain Modifier
Sediment Modifier
Terraform Modifier
Obstacle Cube
Obstacle Sphere
Obstacle Cylinder
Obstacle Elipse
Obstacle Wedge
Obstacle HexPrism
Obstacle Cone
Obstacle Capsule

Shared Settings

The settings panel allows you to configure properties that apply to the object being dragged or the brush being used.

Terrain or Fluid Layer

Selects the target layer for the operation (1–8). When placing a Fluid Source, only layers 1 and 2 are supported. For terrain operations, this corresponds to the specific erosion layer being modified. Layers 5–8 write the second heightmap when eight-layer terrain is enabled. In Sculpt Mode, toggles which heightmap channels receive the stroke. Turn all layers off to paint splat only. Click a layer to select only that layer. Ctrl/Cmd-click toggles a layer on or off without clearing the others. The solo (eye) control hides layers above the highest selected layer in the Scene View preview only.

Splat Channels

Selects the specific color channel (Red, Green, Blue, or Alpha) to modify. This setting is strictly for Terrain Modifiers and is only active when Layer 1 is selected. It has no effect on Fluid Modifiers or Obstacles. In Sculpt Mode on Terraform Terrain, the R/G/B/A buttons paint that splat channel (click again to clear). They are disabled for Smooth, Sharpen, and Slippage.

Blend Mode

Determines how the tool interacts with existing data. Additive adds value to the current height or strength. Set overrides the current value with the specific setting. Minimum blends by taking the lowest value between the modifier and the existing data (useful for digging). Maximum blends by taking the highest value (useful for raising).

In Sculpt Mode, the sculpt tool buttons select the operation directly: + uses Additive, = / < / > use Set / Minimum / Maximum. Smooth, Sharpen, and Slippage use their own operators (not this blend picker).

Tool Properties

These sliders adjust the physical properties of the object being spawned. Size controls the initial scale of the spawned object or the radius of the brush. Str (Strength) controls the intensity or opacity of the modifier. Rot (Rotation) applies an initial Y-axis rotation (0–360°) to the object.

In Sculpt Mode, Size is the brush diameter in world units. Str is how strong each tool paints. Raise, Smooth, and Slippage feel different at the same Str. Set, Min, and Max use Str as how hard you push toward the target height. Rot spins the stamp texture. Shrp appears when Sharpen is selected. Ang appears when Slippage is selected. Use Ctrl/Cmd + scroll, Shift + scroll, and Alt + scroll in the Scene View to change Size, Strength, and Rotation without using the sliders.