clouds_base

A clouds_base material is used to create realistic volumetric clouds. It is applied to CloudLayer object.

Prior Knowledge

This article assumes you have prior knowledge of the following topics. Please read them before proceeding:

The clouds_base material has the following states:

States

Material Editor, States tab.

Self Shadows

This state determines if a cloud layer casts shadows on itself. By default the state is enabled.


Self Shadows enabled.	Self Shadows disabled.

Receive Shadows

This state determines if shadows from an upper cloud layer can be cast on this cloud layer. By default the state is disabled.


Receive Shadows enabled.	Receive Shadows disabled.

Cast Shadows

This state determines if a cloud layer casts shadows. By default the state is enabled.


Cast Shadows enabled.	Cast Shadows disabled.

Fix Coverage Tiling

This state determines if reduction of tiling for the clouds coverage texture is enabled. Such tiling becomes noticeable in large-scale worlds when observing clouds at significant distances. It is recommended to enable this state only when the unwanted effect appears. Please use it wisely, as additional texture fetching affects performance. By default the state is disabled.

Notice

Tiling reduction for clouds should be enabled globally (via Settings -> Rendering -> Clouds -> Fix Tiling).

Textures

Material Editor, Textures tab.

Clouds Coverage#

An RGB8 texture with the following channels:

	Red channel stores a coverage map. It determines cloud density in a horizontal plane. Notice For a number of tuning options to work correctly, this map should not contain absolutely black pixels.
	Green channel stores a stormcloud map. It determines areas of the coverage map, where cumulonimbus clouds are located.
	Blue channel stores a height map. It determines cloud height for each point of the coverage map. Notice Absolutely black color does not correspond to an absolutely flat cloud, it determines a minimum possible cloud thickness for a certain configuration.

Geometry#

Geometry Parameters

Layer Height

Determines the height of the cloud layer.


Layer Height = 100	Layer Height = 500

Coverage Size

Determines the size of the coverage texture.


Coverage Size = 0.3	Coverage Size = 1

Coverage Contrast

This parameter determines the contrast of the coverage texture and can be used for fine tuning. It also makes it possible to gradually increase cloudiness without changing the coverage texture when simulating weather. The lower the value the more cloudy the sky looks.

NoticeFor this parameter to work properly, the coverage texture must not contain absolutely black pixels.


Coverage Contrast = 0.3	Coverage Contrast = 1

Coverage Cloudiness

Intensity of storm clouds coverage that is stored in the Green channel of the Clouds coverage texture.


Storm Cloud Density = 0	Storm Cloud Density = 1

Bottom Fade

Determines the form of clouds bottom. Lower values make the bottom more flat.


Bottom Fade = 0	Bottom Fade = 0.5

Cloud Density

Controls density of the clouds which determines visual appearance. This parameter can be used to simulate cirrus clouds. The default value is 1.

NoticeThis parameter should only be used when the desired visual appearance cannot be achieved using other parameters. The higher is the cloud density, the higher is the performance. Lower density values can significally reduce performance.


Cloud Density = 0.2	Cloud Density = 0.4

Procedural#

Procedural Parameters

Noise Size

Determines noise graininess. The default value is 0.45.

NoticeHigher values reduce performance and may bring up the tiling issue. Recommended range of values is from 0.3 to 1


Noise Size = 0.3	Noise Size = 1

Noise Threshold

Determines the density threshold of cloud formation. The higher the value the rougher the clouds are.

NoticeThis parameter should be used only for fine tuning. Significant changes made to this parameter may result in mismatch of cloud shapes and their shadows.


Noise Threshold = 0.07	Noise Threshold = 0.375

Noise Threshold Extent

This parameter works together with Noise Threshold parameter and adjusts appearance of clouds making it possible to make clouds softer or rougher for a selected noise threshold.

NoticeThis parameter should be used only for fine tuning. Significant changes made to this parameter may result in mismatch of cloud shapes and their shadows.


Noise Threshold Extent = 0.01	Noise Threshold Extent = 0.2

Base Noise Mip Offset

Controls mip levels of the base noise texture in order to reduce blurring at large distances. The recommended range of values is from 0 to 3. Higher values reduce performance.

Detail Noise Size

Determines the size of details cutout from the clouds. This parameter is analogous to the Noise size parameter. The lower is the value the larger pieces are cutout.


Detail Noise Size = 0.01	Detail Noise Size = 5

Detail Distortion Size

Determines the scale of clouds detail distortion according to the corresponding texture. This parameter is used to control detail turbulence. The higher is the value the stronger is the detail turbulence effect.


Detail Distortion Size = 0	Detail Distortion Size = 10

Detail Distortion Force

Determines the intensity of clouds detail distortion. This parameter is used to control detail turbulence. The higher is the value the stronger is the detail turbulence effect.


Detail Distortion Force = 0.5	Detail Distortion Force = 4

Detail Wispy Billowy Gradient

Controls the inversion of detail noise. With the default value of 0, the clouds form is as in the detail texture, increasing the value gradually inverts the values from wispy to billowy and from billowy to wispy.

Detail Intensity

Adjusts detail cutout intensity. Details are cut mostly from the bottom of the clouds.

NoticeThunderclouds are dense and do not have detail cutout. Therefore, they have detail intensity value equal to 0.


Detail Intensity = 0.8	Detail Intensity = 1.4

Shading#

Shading Parameters

Ambient Intensity Top

Determines intensity of ambient lighting of clouds (lighting from above). Analogous to the previous parameter. The higher is the value, the more ambient lighting affects clouds.

Ambient Intensity Bottom

Determines intensity of ambient lighting of clouds (lighting from below). The higher is the value, the more ambient lighting affects clouds.


Ambient Intensity = 0 (Ground color set to ff0000)	Ambient Intensity = 1 (Ground color set to ff0000)

Sun Intensity

Determines intensity of the sun light affecting the clouds (from above). The higher is the value, the more sun lighting affects clouds. This parameter makes it possible to adjust the appearance of clouds by means of correction of sunlight intensity.

Notice

Areas lighted by the sun do not have environment lighting.


Sun intensity = 0	Sun intensity = 1

Haze Gradient

Controls the degree of gradual fading of the clouds to the haze depending on the haze parameters.


Haze Gradient = 0.0	Haze Gradient = 4.0

Sun Saturation

Determines the saturation of the sun light affecting the clouds.

Ambient Saturation

Controls ambient lighting color saturation.


Ambient Saturation = 0.0	Ambient Saturation = 1.0

Sun Attenuation

Controls the amount of sun light passing through clouds without changing their density. The higher the value the less light passes through clouds.

Multiscattering Intensity

Controls the approximation of light scattering in clouds. A view-dependent effect is created to control shadows on clouds: when clouds are looked on against the sun, shadows are more intensive compared to the side view.

Attenuation Coefficient

Controls the rate of opacity growth (alpha channel) with the distance inside the cloud, imitating cloud volume and fixing a break at a certain height appearing in the process of rendering curved cloud layers when viewed from inside the layer.

Inscatter Density Threshold

Determines the density threshold value; if this value is exceeded, the darkening is not applied.

Inscatter Energy Compensation

Compensates for the overall brightness loss from the in-scattering effect.

Inscatter Intensity

Controls the in-scattering effect, which affects the possibility of darkening the edges of clouds.

Other#

Other Parameters

Wind speed (X axis)

Wind speed along X axis (shifts the coverage texture).

Wind speed (Y axis)

Wind speed along Y axis (shifts the coverage texture).


No wind	Wind X = 20, Wind Y = 20

Wind speed (Z axis)

Wind speed along Z axis (shifts noise).


No wind	Wind Z = 100

Wind Deformation

Control dynamics of moving clouds, i.e. how much clouds change their form as they move.

Shadow Intensity

Determines the intensity of shadows cast by clouds. This parameter is used for synchronization of visual appearance of clouds with their shadows.


Shadow intensity = 0.8	Shadow intensity = 1

Shadow Contrast

Determines the contrast of shadows cast by clouds.


Shadow contrast = 0.3	Shadow contrast = 1.0

Shadow Multiplier

Determines darkness of shadows cast by clouds. The lower the value, the darker the shadows are.


Shadow multiplier = 0.3	Shadow multiplier = 1.0

Shadow Subtraction

The higher the value, the larger the area under clouds is covered by the shadow. Decreasing the value causes shadows from clouds to be subtracted from the shadow that covers the area under the clouds.
The parameter can be set to the maximum value, for example, when the shadow cast by the clouds doesn't fully cover the area beneath, however, clouds look dense enough.


Shadow subtraction = 0.2	Shadow subtraction = 0.4

FieldWeather Mask

Bitmask that determines interaction with FieldWeather objects.

In This Article:

States#

Textures#