USDMeshLight

Turns mesh primitives into USD mesh lights by assigning a MeshLight shader and adding the meshes to the default lights set.

user

Container for user-defined plugs. Nodes should never make their own plugs here, so users are free to do as they wish.

enabled

The on/off state of the node. When it is off, the node outputs the input scene unchanged.

filter

The filter used to control which parts of the scene are processed. A Filter node should be connected here.

parameters

The parameters of the light shader applied to the mesh.

parameters.intensity

The base intensity of the light. Scales the brightness of the light linearly.

parameters.exposure

Exposure setting of the light. Scales the brightness of the light exponentially.

parameters.color

The color of the emitted light, in the rendering color space.

parameters.enableColorTemperature

Controls whether colorTemperature is used.

parameters.colorTemperature

The color temperature of the light, in degrees Kelvin.

parameters.specular

A multiplier for the effect of this light on the specular response of materials.

parameters.diffuse

A multiplier for the effect of this light on the diffuse response of materials.

parameters.ri:light:intensityNearDist

intensityNearDist: Near distance between the point being illuminated and the light at which the sample doesn’t get brighter. This may help you avoid hot spots and sampling issues where a light is near a surface.

parameters.ri:light:specularNearDist

specularNearDist: Near distance between the point with specular shading being illuminated and the light at which the sample doesn’t get brighter. This may help you avoid hot spots and sampling issues where a light is near a specular surface. Note that this value will not apply to lights as seen from the camera.

parameters.ri:light:diffuseNearDist

diffuseNearDist: Near distance between the point with diffuse shading being illuminated and the light at which the sample doesn’t get brighter. This may help you avoid hot spots and sampling issues where a light is near a diffuse surface. Note that this value will not apply to lights as seen from the camera.

parameters.ri:light:msApprox

Enable volume multi-scattering approximation. When enabled, volume multi-scattering approximation mimics the effect of multi-scattering in aggregate volumes.

parameters.ri:light:msApproxBleed

The color of the light bleed from volume multi-scattering approximation. Controls how much light bleeds into the volumes illuminated by this light. Has no effect if ‘Gain’ (msApprox) is set to 0.

parameters.ri:light:msApproxContribution

The color of the contribution of light from volume multi-scattering approximation. Controls how much the light bleed contributes to the brightness of volumes illuminated by this light. Has no effect if ‘Gain’ (msApprox) is set to 0.

parameters.normalize

Controls if the light power should be normalized by the surface area of the light. If enabled, the light power remains constant if the light’s area or angular size is changed.

parameters.ri:light:traceLightPaths

Enables light and photon tracing from this light. This value enforces a physically-based light and as a side-effect disables thinShadow and visibleInRefractionPath. Users may use this feature to selectively decide which lights emit photons when using the PxrVCM or PxrUnified Integrators. Because it will automatically disable thin shadows, this should not be enabled when using the PxrPathTracer integrator.

parameters.ri:light:thinShadow

thinShadow: Enable thin shadow and disable refraction caustics for this light. This parameter will be ignored if Trace Light Paths is enabled. This is a non-physical control that creates “fake” colored shadows for transmissive objects without needing to generate photons for caustics. Also for the paths where Cheap Caustics is enabled (surfaces marked “MWWalkable”), then thinShadow is ignored as well.

parameters.ri:light:visibleInRefractionPath

visibleInRefractionPath: Make this light source visible in refraction paths. This parameter will be ignored if Cheap Caustics is enabled.

parameters.ri:light:cheapCaustics

Enable manifold walk computation and disable thin shadow for this light. This parameter will be ignored if Trace Light Paths is enabled.

parameters.ri:light:cheapCausticsExcludeGroup

Specifies the exclude shadow subset for manifold walk. Will be used to prevent occlusion during the search of caustic path.

parameters.ri:light:importanceMultiplier

Importance of this light for noise control.

parameters.ri:light:lightGroup

lightGroup: Specify the light group name used for light group LPEs. This is useful to generate per-light AOVs for later adjustment in compositing.