The V-Ray Luminaire light allows efficient rendering of entire light fixtures by loading their respective precomputed light fields from .vlw files.

Such files are generated by Chaos and used in Chaos Cosmos light assets marked with a "Luminaire" tag.

There is only initial support for V-Ray Luminaire in V-Ray GPU. Artifacts and errors may come up.

You can access the Luminaire Light's parameters by expanding the Cosmos asset containing the light and selecting the Luminaire Light Source .

Besides the Luminaire Light, a standard light is also created to allow light to shine within the lamp geometry. Depending on the lamp type, a different light serves this purpose. See the page for your corresponding standard light on the Lights landing page.

Enabled – Turns the VRayLuminaire light on and off.

Color – Specifies the tint color of the Luminaire Light.

Intensity – Sets an intensity multiplier.

File – Specifies the .vlw file that holds the baked lighting.

Units – Choose the light units. Using the correct units is essential when using the V-Ray Physical Camera. The light automatically takes the scene's unit scale into consideration to produce the correct result for the scale you are working with. The possible values are:

Default – The color and multiplier directly determine the visible color of the light without any conversion. The light surface appears with the given color in the final image when seen directly by the camera (assuming there is no color mapping involved).
Lumens – Total emitted visible light power measured in lumens. When this setting is used, the intensity of the light does not depend on its size. A typical 100W electric bulb emits about 1500 lumens of light. Note that V-Ray uses a conversion unit of 683 lum/watt, that is, the maximum physical possible Luminous efficacy.
lm/m/m/sr – Visible light surface power measured in lumens per square meter per steradian. When this setting is used, the intensity of the light depends on its size.
Watts – Total emitted visible light power measured in watts. With this setting, the intensity of the light does not depend on its size. Keep in mind that this is not the same as the electric power consumed by a light bulb, for example. A typical 100W light bulb only emits between 2 and 3 watts of visible light. Note that V-Ray uses a conversion unit of 683 lum/watt, that is, the maximum physical possible Luminous efficacy.
w/m/m/sr – Visible light surface power measured in watts per square meter per steradian. When this setting is used, the intensity of the light depends on its size. 

Filtering On – Enables stochastic filtering of the light field to reduce aliasing.

Filter Strength – Specifies the strength of the stochastic filtering of the light field.

Lo D On – 

Scale – Allows the loaded asset to be scaled up or down.

Invisible – Controls whether the shape of the light source is visible in the render result. When this option is enabled, the light source is not visible in the rendering. When this option is disabled, if the light source is seen directly by the camera or through refractions, it appears in renderings in the current light color.

Affect Diffuse – Determines whether the light affects the diffuse properties of the materials.

Affect Specular – Determines whether the light affects the specular properties of the materials. This means glossy reflections.

Affect Atmospherics – When enabled, the light influences the atmospheric effects in the scene. This option is not available with V-Ray GPU.

Diffuse Contribution – A multiplier for the effect of the light on the diffuse component.

Specular Contribution – A multiplier for the effect of the light on the specular component.

Atmospherics Contribution – Determines the amount of influence the light has on the atmospheric effects.

LPE Label – Allows a label to be assigned, which can be used to reference the light in a Light Path Expression. This is especially useful when working with the Light Select render element to evaluate custom light contributions in the scene.

Shadows – When enabled (the default), the light casts shadows. Disable this option to turn off shadows for the light.

Shadow Color – Controls the color of shadows for this light. Note that anything different from black is not physically correct. 

Shadow Bias – Moves the shadow toward or away from the shadow-casting object (or objects). Higher values move the shadow toward the object(s), while lower values move it away. If this value is too extreme, shadows can "leak" through places they shouldn't or "detach" from an object. Other effects from extreme values include Moire patterns, out-of-place dark areas on surfaces, and shadows not appearing at all in the rendering.

Caustics Subdivs – Only used when calculating Caustics. Lower values mean more noisy results but render faster. Higher values produce smoother results but take more time.

Caustics Multiplier – This value is a multiplier for the generated caustics by the selected object. Note that this multiplier is cumulative - it does not override the multiplier in the Caustics render settings rollout section.

Cut-off Threshold – Specifies a threshold for the light intensity below which the light is not computed. This can be useful in scenes with many lights, where you want to limit the effect of the lights to some distance around them. Larger values cut away more of the light; lower values make the light range larger. When this value is 0.0, the light is calculated for all surfaces.

Near Decay On – Toggles near decay on and off.

Near Decay Start – Determines where the fade in starts. Anything before this point is rendered dark.

Near Decay End – Determines where the fade in ends. After this threshold, the light is at its full value.

Far Decay On – Toggles far decay on and off.

Far Decay Start – Determines where the fade off starts.

Far Decay End – Determines where the light reaches a value of 0, i.e. completely fades off. See the Far Decay End example for more.

Project is used to create a list of objects that can be excluded (or included) from the light's effects, such as illumination or shadow casting.

Mode – Specifies whether the objects in the list are considered Included or Excluded from the light's effects.

Objects – Creates a list of objects to be excluded or included. When an object is added to the list, the  icons appear, which determine how the light affects the object. The  icon controls whether the emitted light affects the object. The  icon controls whether the shadows caused by the light affect the object. The  determines whether the object's children are affected.

Relink Cosmos Asset – If the asset is misplaced or missing from the scene, it will appear in the Objects tab with this icon . Clicking on this option will automatically relink the asset to the scene.

Alternatively, you can relink assets using the Download Cosmos Assets tool.