Settings and properties related to the Water System

This page explains the settings and properties you can use to configure the:

• Water Volume Inspector
• Water System Volume Override
• Water System in the Rendering Debugger
• Water System in the HDRP Asset

Water Volume Inspector

Additional properties

To see properties related to Fade, Caustics Intensity, and Caustics Plane Band Distance, you must enable them in Preferences > Core Render Pipeline. Select the Visibility option All Visible. These properties are not visible by default because they are not essential to use the feature, being primarily for performance optimization.

Water type			Property	Description
Pool	River	Ocean, Sea, or Lake
X	X	X	General
			Surface Type	Specifies the type of water body that this surface should imitate.
			Geometry Type	Specifies the shape of the water surface. The options are: Quad: Based on a square. Custom Mesh: Based on a Mesh you provide. Overrides the vertical position of the vertices to keep the surface of the water consistently level. Infinite (Ocean, Sea, or Lake only): Bounds the water surface with the Global Volume.
			Script Interactions	Enable to have HDRP calculate the height of the water simulation on the CPU. Increases visual fidelity but demands more from the CPU. See Scripting in the Water System for more information.
			- Full Resolution	Only available if Script Interactions is active. Enable to have HDRP calculate the CPU simulation at full resolution. Otherwise, HDRP calculates the simulation at half resolution. Full resolution simulations demand more from the CPU.
			- Evaluate Ripples	Only available if Script Interactions is active. Enable to have HDRP include ripples in the simulation on the CPU. Increases visual fidelity, but demands more from the CPU.
X	X	X	Simulation
			Time Multiplier	Determines the speed at which HDRP presents the water simulation. Values above 1 increase the simulation speed; values lower than 1 decrease it.
			Water Mask	A texture HDRP uses to attenuate or supress Ripple (green channel) and Swell or Agitation (red channel) water frequencies. For more information, see Decals and masking in the Water System.
	X	X	River surface types: Agitation Ocean, Sea, or Lake surface types: Swell
			Repetition Size	The size of the water patch in meters. Higher values result in less visible repetition. Also affects the Maximum Amplitude of Swell or Agitation frequency bands.
			Distant Wind Speed	Represents the speed of distant wind in kilometers per hour. This property indirectly determines the Maximum Amplitude and shape of the swell in a nonlinear way. Nonlinear means that changes to Distant Wind Speed do not have a proportional effect on swells.
			Distant Wind Orientation	Represents the orientation of distant wind counterclockwise to the world space X vector. (This vector aligns with the blue handle of the Transform Gizmo). Only affects a swell with a Chaos value less than 1.
			Chaos	Determines how much the Local Wind Orientation affects ripples; values less than 1 increase Local Wind Orientation's influence. Values more than 1 decrease Local Wind Orientation's influence.
			Current	Translates the swell at a constant speed in the given direction. Speed: Determines how fast the current moves, measured in kilometers per hour. Orientation: Determines the orientation of the current in degrees relative counterclockwise to the world space X vector. (This vector aligns with the blue handle of the Transform Gizmo).
	X	X	Simulation Band properties
			Amplitude Multiplier	Amplitude Multiplier (Ocean, Sea, or Lake) First band: The degree to which amplitude attenuates on the first frequency band of the Swell. Second Band: The degree to which amplitude attenuates on the second frequency band of the Swell. Amplitude Multiplier (River) A multiplier that determines the degree to which amplitude can attenuate on the Agitation frequency band. For example, if your Amplitude value is 10 meters and you set this property to 0.5, your Agitation is 5 meters high.
			Fade	Additional property. When this option is active, HDRP begins fading the contribution of this frequency band at the distance from the camera that the Range value specifies. This helps minimize distant aliasing artifacts.
			- Range	Additional property. The distance from the camera in meters at which HDRP begins to fade the contribution of this frequency band.
			Total Amplitude	The combined amplitude of all bands.
		X	Simulation Band property specific to Ocean, Sea, or Lake, appears after Amplitude Mulitplier for each band.
			Max Amplitude	The amplitude of this band, in meters. This is the sum of the original amplitude and the multiplied amplitude.
X	X	X	Ripples
			Local Wind Speed	Represents the speed of local wind blowing over the water surface in kilometers per hour. This determines the maximum amplitude and shape of ripples indirectly, in a nonlinear way. Nonlinear means that changes to Local Wind Speed do not have a proportional effect on ripples.
			Local Wind Orientation	Represents the orientation of local wind counterclockwise to the world space X vector. (This vector aligns with the blue handle of the Transform Gizmo). Only affects ripples with a Chaos value less than 1. River and Ocean, Sea, or Lake only: If set to 0, matches the Distant Wind Orientation.
			Chaos	Determines how much the Local Wind Orientation affects ripples; values below 1 increase Local Wind Orientation's influence. Values above 1 decrease the influence of Local Wind Orientation.
			Current	Pool: Determines the orientation and constant speed of the swells that displace ripples in the pool. River: Determines the orientation and constant speed of the current that displaces ripples in the river. By default, River Current inherits the Agitation values, but you can also set custom orientation and speed values. Ocean, Sea, or Lake: Determines the orientation and constant speed of the current that displaces ripples in the river. By default, Ocean, Sea, or Lake Current inherits the Swell values, but you can also set custom orientation and speed values. Speed: Determines how fast the current moves, measured in kilometers per hour. Orientation: Determines the orientation of the current in degrees relative counterclockwise to the world space X vector. (This vector aligns with the blue handle of the Transform Gizmo).
			Fade	Additional property. When this option is active, HDRP begins fading the contribution of this frequency band at the distance from the camera that corresponds to the Range value in meters. This helps minimize distant aliasing artifacts.
			- Range	Additional property. The distance from the camera, in meters, at which HDRP begins to fade the contribution of this frequency band.
x	X	X	Deformation
			Enable	Specify if this surface supports deformation..
			Resolution	The resolution of the deformation texture used to represent the deformation area. 256 x 256: Set the deformation texture to 256 x 256 pixels. 512 x 512: Set the deformation texture to 512 x 512 pixels. 1024 x 1024: Set the deformation texture to 1024 x 1024 pixels. 2048 x 2048: Set the deformation texture to 2048 x 2048 pixels.
			Area Size	Set the size of the deformation area in meters.
			Area Offset	Set the offset of the deformation area in meters
	X	X	Foam
			Simulation Foam Amount	Determines the amount of surface foam. Higher values generate larger foam patches. The Wind Speed Dimmer configuration determines which Distant Wind Speed values generate foam, and how much; see Foam in the water system.
			Simulation Foam Smoothness	Determines the lifespan of surface foam. Higher values cause foam to persist longer and leave a trail.
			Texture Tiling	Determines the tile size of the foam texture, in meters.
			Custom Texture	Choose a texture Unity can use to define foam's appearance. If this is None, HDRP uses the default texture.
			Mask	Select a texture whose red channel Unity uses to attenuate and suppress foam.
			Wind Speed Dimmer	Determines foam intensity. The normalized Distant Wind Speed determines the X axis value. The spline editor configures the Y axis value. See Foam in the water system for more information.
X	X	X	Appearance
			Custom Material	Select a custom material Unity can use to render the water surface. If this is None, Unity uses the default material.
			Smoothness
			Close	Determines how detailed the water surface is when closer to the Scene camera than the smoothness Fade Start value.
			- Distant	Determines how detailed the water surface is when further from the Scene camera than the smoothness Fade Distance value.
			Fade Range	Specifies the range over which Unity interpolates smoothness from close to distant. Start: Determines the distance in meters from the Scene camera at which HDRP begins removing detail and interpolating the smoothness value for the water surface. Distance: Determines the distance in meters from the Start point at which the Distant smoothness value takes effect.
			Refraction
			Color	Determines the color HDRP uses to simulate underwater refraction.
			Maximum Distance	Determines the maximum distance from the Scene camera Unity renders underwater refraction. Higher values increase the distortion amount.
			Absorption Distance	Determines how deep into the water the camera can perceive, in meters.
			Scattering
			Color	Determines the color that Unity uses to simulate underwater scattering.
			Ambient Term	Determines the intensity of the ambient scattering term.
			Height Term	Determines the intensity of height-based scattering. The higher the vertical displacement, the more the water receives scattering. You can adjust this for artistic purposes.
			Displacement Term	Determines the intensity of displacement-based scattering. The larger this value is, the more the water receives scattering.
			Direct Light Body Term	Determines the intensity of direct light scattering on the bodies of waves.
	X	X	Direct Light Tip Term	Determines the intensity of direct light scattering on the tips of waves. You can perceive this effect more at grazing angles.
X	X	X	Caustics
X	X	X	Caustics	Enable to render caustics.
			Caustics Resolution	The resolution at which Unity renders caustics in the simulation.
	X	X	Simulation Band	Determines which Simulation Band Unity uses for caustics evaluation. For Ocean, Sea, or Lake water surfaces, the Swell simulation determines the first (index 0) and second (index 1) simulation band values. Ripples determine the third band value (index 2). The River type has two Simulation Bands, one for Agitation simulation and one for Ripples. For the Pool type, ripples determine the caustics evaluation. A higher Local Wind Speed value results in larger, looser caustics.
X	X	X	Virtual Plane Distance	Determines the distance from the camera at which Unity projects simulated caustics. High values generate sharper caustics but can cause artifacts. The larger the waves are, the further the plane distance should be to obtain sharp caustics.
			Caustics Intensity	Additional property. The normalized intensity of underwater caustics.
			Caustics Plane Blend Distance	Additional property. The vertical blending distance of the water caustics, in meters from the camera.
X	X	X	Underwater
			Volume Bounds	Specifies the collider Unity uses to determine the volume in which it applies the underwater effect for non-infinite water surfaces.
			Volume Priority	Determines which surface Unity prioritizes for underwater rendering when multiple water surfaces overlap. Unity renders surfaces with a higher value first.
			Transition Size	Where the distance between the camera and the water surface is lower than or equal to this value, Unity begins to blend the water surface rendering with the underwater rendering to prevent a sharp cutoff between them.
			Absorption Distance Multiplier	Determines how far the camera can see underwater. For example, a value of 2.0 means the camera can see twice as far underwater as you can from the water surface.
X	X	X	Miscellaneous
			Decal Layer Mask	Specifies the decal layers that render on the water surface. To use this feature, enable Decal Layers in your HDRP Asset.
			Light Layer Mask	Specifies the light layers that affect the water surface. To use this feature, enable Light Layers in your HDRP Asset.

Water System Volume Override

To use a Volume Override, you must first add a Volume Profile.

See The Water System Volume Override for more information.

Property	Description
General
Enable	Enable the override to render water surfaces.
Level of Detail
Min Grid Size	Determines the minimum water grid size in meters. The Grid is the geometry Unity uses to render the water, which is always a square. Min Grid Size determines the size of the central patch for the closest Level of Detail (LOD), and the other LOD sizes are mulipliers of Min Grid Size.
Max Grid Size	Determines the maximum water grid size in meters.
Elevation Transition	Determines the elevation at which Unity reaches the maximum water grid size.
Num Level of Details	The Patch is the size of the area on which Unity runs the simulation for a particular Simulation Band. Determines the number of LOD patches that Unity renders for water. One level of detail (LOD) means one patch represents the water surface. Two LOD levels means that 8 patches surround the the central patch, three LODs means 16 patches around the central one, and this formula remains the same as the LOD level increases.
Tessellation (Additional property set)
Max Tessellation Factor	Additional property. The maximum tessellation factor for the water surface. Determines how many subdivisions the water surface can have.
Tessellation Factor Fade Start	Additional property. Determines the distance from the camera at which the tessellation factor begins to decrease.
Tessellation Factor Fade Range	Additional property. Determines the distance from the camera at which the tessellation factor reaches 0.
Lighting
Ambient Probe Dimmer	Determines the influence of the ambient light probe on the water surface.

Water System in the Rendering Debugger

The Main Camera and Scene Camera Rendering tabs of the Rendering Debugger window include Water among their frame settings.

Water System in the HDRP Asset

You enable the Water System in the HDRP Asset as the Use the Water System in your Project describes. You can also adjust several related settings in the HDRP Asset.