Sky light

This command simulated both direct sunlight and ambient lighting from the sky. This radiation is much more diffuse than other light, providing much softer lighting.

Creation Stages / Use:

Click the icon or select Visualization > Lights > Sky Light... from the drop-down menu.

Sky light: Defines the various sky parameters.

Select the turbidity of the sky: a value near 0 indicates a clear sky, a vue near 10, a sky very polluting.
Specify the factor of albedo. It is the fraction of sun energy which is reflected by the floor. The more the surface is reflecting, the higher is albedo.
Specify the factor of saturation. This factor allows to modulate the sky color. A value of 100% corresponds to the color of a clear sky, a value near 0 corresponds to a grey sky.
Select the intensity by dragging the cursor or entering the value. A value of 100% corresponds to the intensity of a clear sky. A lower value allows to simulate a cloudy sky.
Indicate the direction of north.
Indicate the direction of the zenith.
Choose whether to enable shadows.

Sun: Defines the various sun parameters (position, color, and intensity).

Enter the azimuth and altitude, or click the Position calculator button.
Select the intensity by dragging the cursor or entering the value. A value of 100% corresponds to the intensity of sun with a clear weather. A lower value allows to simulate the sun veiled by clouds.

Clouds: Defines the various clouds parameters.

Cumulus/Stratus:

Density: percentage defining the density of clouds (compact, thick and tight).
Opacity: percentage defining the opposition to the passage of light.

Cirrus:

Type: cirrus type to use (5 types available).
Opacity: percentage defining the opposition to the passage of light.

Luminosity: percentage of light emission.
Random seed: integer between 1 and 10000 to simulate a random position of clouds in the sky.

Colors of the sky and the sun are automatically defined regarding the sun position (orange in the morning or evening, blue during the day, ....)
Clouds: position the mouse cursor on the Cumulus/Stratus button or on the Type field of Cirrus to see a preview of clouds.

Openings:

If the sky light can pass through faces (windows, or others, ...), select them to reduce rendering calculations.