filament/io.github.erkko68.filament/FogOptions

FogOptions

Options to control large-scale fog in the scene.

Materials can enable the linearFog property, which uses a simplified, linear equation for fog calculation; in this mode, the heightFalloff is ignored as well as the mipmap selection in IBL or skyColor mode.

Constructors

FogOptions

constructor()

Properties

color

var color: FloatArray

Fog's color used for ambient light in-scattering. A good value is the average of the ambient light, possibly tinted towards blue for outdoor environments. Color components should be between 0 and 1; values above 1 are allowed but could create a non energy-conservative fog. Used as a tint when fogColorFromIbl is enabled. Default: white.

cutOffDistance

var cutOffDistance: Float

Distance in world units m after which the fog calculation is disabled. This can be used to exclude the skybox. The SkyBox is typically at a distance of 1e19 in world space. Default: infinity.

density

var density: Float

Extinction factor in 1/m at the fog height. Controls how much light is absorbed and out-scattered per unit of distance. Each unit of extinction reduces incoming light to 37% of its original value. In linearFog mode, this is the slope of the linear equation if heightFalloff is 0. Default: 0.1.

distance

var distance: Float

Distance in world units m from the camera to where the fog starts (>= 0.0). Default: 0.0.

enabled

var enabled: Boolean

Enable or disable large-scale fog. Default: false.

fogColorFromIbl

var fogColorFromIbl: Boolean

The fog color will be sampled from the IBL in the view direction and tinted by the color parameter. This simulates a more anisotropic phase-function. Ignored when skyColor is specified. Default: false.

height

var height: Float

Fog's floor in world units m. This sets the "sea level". Default: 0.0.

heightFalloff

var heightFalloff: Float

How fast the fog dissipates with altitude. heightFalloff has a unit of 1/m. It can be expressed as 1/H, where H is the altitude change in world units m that causes a factor 2.78 (e) change in fog density. A falloff of 0 means the fog density is constant everywhere. Ignored in linearFog mode if set to 0. Default: 1.0.

inScatteringSize

var inScatteringSize: Float

Very inaccurately simulates the Sun's in-scattering. Size of the Sun in-scattering (>0 to activate). Good values are >> 1 (e.g., ~10 - 100). Smaller values result in a larger scattering size. Ignored in linearFog mode. Default: -1.0.

inScatteringStart

var inScatteringStart: Float

Distance in world units m from the camera where the Sun in-scattering starts. Ignored in linearFog mode. Default: 0.0.

maximumOpacity

var maximumOpacity: Float

Fog's maximum opacity between 0 and 1. Ignored in linearFog mode. Default: 1.0.

skyColor

var skyColor: Texture?

Optional sky texture (mipmapped cubemap) for fog color sampling. When provided, the fog color will be sampled from this texture, with higher resolution mip levels used for objects at the far clip plane and lower resolution mip levels for closer objects. fogColorFromIbl is ignored when this is specified. In linearFog mode, mipmap level 0 is always used. Default: null.