This page describes the Aerial Perspective atmospheric approximation.
Overview
The VRayAerialPerspective atmospheric effect simulates aerial perspective - the effect that the Earth atmosphere has on the appearance of objects that are viewed from a distance, and which is similar to fog or haze. The atmospheric effect works together with the VRaySun and the VRaySky to calculate an approximation to the aerial perspective effect. It is faster to calculate than the VRayEnvironmentFog atmospheric, although the result is just an approximation - for example, the VRayAerialPerspective atmospheric cannot produce volumetric shadows.
UI Path
||Hypershade|| > Create panel > VRay section > Volumetric > VRay Aerial Perspective
Parameters
Sun – Specifies the V-Ray Sun object in the scene that the Aerial Perspective effect is connected to.
Enabled – Turns the atmospheric effect on or off.
Distance (m) – Specifies the distance, in meters, at which the fog has absorbed 90% of the light coming from objects behind it. Lower values make the fog appear more dense, while larger values reduce the effect of the aerial perspective. For more information, see the Visible Distance example below.
Atmospheric Height (m) – Controls the height of the atmosphere layer, in meters. Lower values can be used for artistic effects. The value is in meters and is converted internally based on the current Maya units. For more information, see the Visible Height example below.
Inscattered Light Mult. – Controls the amount of sunlight scattered from the atmospheric effect. The default value 1.0 is physically accurate; lower or higher values could be used for artistic purposes.
Affect Environment – When Disabled, the atmospheric effect is applied only to camera rays that hit actual objects, but not to rays that hit the sky. This is because the VRaySky texture already takes into account the amount of scattered sunlight. However, it is possible to enable this option for artistic effects, especially with low visibility ranges. For more information, see the Affect Environment Rays example below.
Affect Background – Specifies whether the effect is applied to camera rays that hit the background (if a background other than VRaySky is used). Normally this option should be disabled, but some interesting effects are possible when this option is enabled.
Filter Color – Affects the color of the unscattered light.
Example: Visibility Distance
Distance is 20000 meters
Distance is 100000 meters
Example: Visibility Height
Atmospheric Height is 20000 meters
Atmospheric Height is 60000 meters
Example: Affect Environment Rays
Aerial Perspective is Disabled
Aerial Perspective is Enabled, Affect Environment is Disabled
The sky color and sun shadows are unaffected by the mist effect
Aerial Perspective is Enabled, Affect Environment is Enabled
The mist effect blocks the sky and the sun light