Lights

Generated from the schema registry by ernie schema --markdown.

LightAPI

What every light has: brightness, colour, and Ernie's polarization and pulses.

API schema · Built in: CollectionAPI · Built in: CollectionAPI

Attribute	Type	Description	Fallback	Values	Source
light:shaderId	token	The light's shader, as renderers name it.	""		UsdLux
light:materialSyncMode	token	For geometry that emits: whether its bound material's glow tints the light, is lit independently, or is ignored.	"noMaterialResponse"	materialGlowTintsLight, independent, noMaterialResponse	UsdLux
inputs:intensity	double	Brightness, scaled by 2^exposure.	1.0	≥ 0	UsdLux
inputs:exposure	double	Stops of brightness, as photographers count them.	0.0		UsdLux
inputs:diffuse	double	Multiplier of its diffuse response.	1.0	≥ 0	UsdLux
inputs:specular	double	Multiplier of its specular response.	1.0	≥ 0	UsdLux
inputs:normalize	bool	Divides its power by its area, so resizing it leaves its brightness.	false		UsdLux
inputs:color	color3d	Linear RGB tint.	[1.0,1.0,1.0]	≥ 0	UsdLux
inputs:enableColorTemperature	bool	Tints it by its colour temperature too.	false		UsdLux
inputs:colorTemperature	double	Kelvin, a black body's.	6500.0	> 0	UsdLux
ernie:polarization:degree	double	The fraction of its light linearly polarized.	0.0	≥ 0, ≤ 1	Ernie
ernie:polarization:angle	double	Degrees from the light's +x to its electric field.	0.0		Ernie
ernie:pulse:rate	double	Pulses per second, a strobe's; 0 continuous.	0.0	≥ 0	Ernie
ernie:pulse:width	double	Seconds each pulse lasts.	0.0	≥ 0	Ernie
ernie:pulse:delay	double	Seconds on the sensor clock, or after the exposure opens, a pulse starts.	0.0		Ernie
ernie:pulse:decay	double	Seconds its level takes to fall by e over a pulse, as a xenon flash's; 0 flat.	0.0	≥ 0	Ernie
ernie:pulse:jitter	double	Seconds each pulse may start early or late.	0.0	≥ 0	Ernie
ernie:pulse:trigger	token	The sensor clock, or the camera's exposure: one pulse a frame, its delay after it opens.	"clock"	clock, exposure	Ernie

Fallbacks it changes: collection:lightLink:includeRoot true; collection:shadowLink:includeRoot true.

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/LightAPI": {
      "typeName": "Xform",
      "apiSchemas": ["LightAPI"],
      "light:materialSyncMode": "noMaterialResponse",
      "inputs:intensity": 1.0,
      "inputs:exposure": 0.0,
      "inputs:diffuse": 1.0,
      "inputs:specular": 1.0,
      "inputs:normalize": false,
      "inputs:color": [1.0, 1.0, 1.0],
      "inputs:enableColorTemperature": false,
      "inputs:colorTemperature": 6500.0,
      "ernie:polarization:degree": 0.0,
      "ernie:polarization:angle": 0.0,
      "ernie:pulse:rate": 0.0,
      "ernie:pulse:width": 0.0,
      "ernie:pulse:delay": 0.0,
      "ernie:pulse:decay": 0.0,
      "ernie:pulse:jitter": 0.0,
      "ernie:pulse:trigger": "clock"
    }
  }
}

BoundableLightBase

A light with a shape, bounded by it.

Abstract base · Inherits Boundable · Built in: LightAPI

Attribute	Type	Description	Fallback	Values	Source
ernie:power	double	Radiant flux in watts, scaling the illuminant's spectral shape; authored, it sets the brightness unless photometric values are authored.	0.0	≥ 0	Ernie

NonboundableLightBase

A light at infinity or around everything, so unbounded.

Abstract base · Inherits Xformable · Built in: LightAPI

DistantLight

A light from infinitely far along +z, such as the Sun's.

Prim type · Inherits NonboundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:angle	double	Angular diameter in degrees; the Sun's is 0.53.	0.53	≥ 0, ≤ 360	UsdLux
ernie:irradiance	double	W m^-2 at normal incidence (the Sun's at 1 au), scaling the illuminant's spectral shape; authored, it sets the brightness unless photometric values are authored.	1361.0	≥ 0	Ernie

Fallbacks it changes: inputs:intensity 50000.0.

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/DistantLight": {
      "typeName": "DistantLight",
      "inputs:angle": 0.53,
      "ernie:irradiance": 1361.0
    }
  }
}

DiskLight

A disk emitting towards -z.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:radius	double	Metres; a disk facing -z.	0.5	≥ 0	UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/DiskLight": {
      "typeName": "DiskLight",
      "inputs:radius": 0.5
    }
  }
}

RectLight

A rectangle emitting towards -z.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:width	double	Metres along x; a rectangle facing -z.	1.0	≥ 0	UsdLux
inputs:height	double	Metres along y.	1.0	≥ 0	UsdLux
inputs:texture:file	asset	An image it emits.	""		UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/RectLight": {
      "typeName": "RectLight",
      "inputs:width": 1.0,
      "inputs:height": 1.0
    }
  }
}

SphereLight

A sphere emitting outwards.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:radius	double	Metres.	0.5	≥ 0	UsdLux
treatAsPoint	bool	Lights as a point however large it is.	false		UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/SphereLight": {
      "typeName": "SphereLight",
      "inputs:radius": 0.5,
      "treatAsPoint": false
    }
  }
}

CylinderLight

A cylinder along x emitting outwards.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:length	double	Metres along x.	1.0	≥ 0	UsdLux
inputs:radius	double	Metres.	0.5	≥ 0	UsdLux
treatAsLine	bool	Lights as a line however thick it is.	false		UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/CylinderLight": {
      "typeName": "CylinderLight",
      "inputs:length": 1.0,
      "inputs:radius": 0.5,
      "treatAsLine": false
    }
  }
}

DomeLight

Light from all around, from an environment image.

Prim type · Inherits NonboundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:texture:file	asset	The environment it emits.	""		UsdLux
inputs:texture:format	token	The texture's mapping.	"automatic"	automatic, latlong, mirroredBall, angular, cubeMapVerticalCross	UsdLux
ernie:texture	float tensor, rank 3	float32 (rows, columns, 3 or 4) linear RGB in memory, latitude-longitude about +z, in place of the file.			Ernie
portals	rel[]	Portal lights its light enters through.	[]		UsdLux
guideRadius	double	Metres to the sphere drawn as its guide.	100000.0	> 0	UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/DomeLight": {
      "typeName": "DomeLight",
      "inputs:texture:format": "automatic",
      "guideRadius": 100000.0
    }
  }
}

PortalLight

A rectangle a dome light's light comes in through, guiding its samples.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
inputs:width	double	Metres along x.	1.0	≥ 0	UsdLux
inputs:height	double	Metres along y.	1.0	≥ 0	UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/PortalLight": {
      "typeName": "PortalLight",
      "inputs:width": 1.0,
      "inputs:height": 1.0
    }
  }
}

MeshLightAPI

Makes a Mesh emit, its bound material's glow tinting the light.

API schema · Built in: LightAPI · Applies to Mesh

Fallbacks it changes: light:shaderId "MeshLight"; light:materialSyncMode "materialGlowTintsLight".

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/MeshLightAPI": {
      "typeName": "Mesh",
      "apiSchemas": ["MeshLightAPI"]
    }
  }
}

VolumeLightAPI

Makes a Volume emit, its bound material's glow tinting the light.

API schema · Built in: LightAPI · Applies to Volume

Fallbacks it changes: light:shaderId "VolumeLight"; light:materialSyncMode "materialGlowTintsLight".

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/VolumeLightAPI": {
      "typeName": "Volume",
      "apiSchemas": ["VolumeLightAPI"]
    }
  }
}

ShapingAPI

Focuses a light, limits it to a cone, or shapes it by an IES profile.

API schema

Attribute	Type	Description	Fallback	Values	Source
inputs:shaping:focus	double	Concentrates its light towards -z.	0.0	≥ 0	UsdLux
inputs:shaping:focusTint	color3d	The colour of what the focus takes away.	[0.0,0.0,0.0]		UsdLux
inputs:shaping:cone:angle	double	Degrees from -z it lights.	90.0	≥ 0, ≤ 180	UsdLux
inputs:shaping:cone:softness	double	How gradually the cone's edge falls off.	0.0	≥ 0	UsdLux
inputs:shaping:ies:file	asset	An IES LM-63 profile.	""		UsdLux
inputs:shaping:ies:angleScale	double	Widens or narrows the profile's angles.	0.0		UsdLux
inputs:shaping:ies:normalize	bool	Keeps the profile from changing the light's power.	false		UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/ShapingAPI": {
      "typeName": "Xform",
      "apiSchemas": ["ShapingAPI"],
      "inputs:shaping:focus": 0.0,
      "inputs:shaping:focusTint": [0.0, 0.0, 0.0],
      "inputs:shaping:cone:angle": 90.0,
      "inputs:shaping:cone:softness": 0.0,
      "inputs:shaping:ies:angleScale": 0.0,
      "inputs:shaping:ies:normalize": false
    }
  }
}

ShadowAPI

Controls a light's shadows.

API schema

Attribute	Type	Description	Fallback	Values	Source
inputs:shadow:enable	bool	Whether it casts shadows.	true		UsdLux
inputs:shadow:color	color3d	The colour of shadows.	[0.0,0.0,0.0]		UsdLux
inputs:shadow:distance	double	Metres shadow rays reach; -1 for no limit.	-1.0		UsdLux
inputs:shadow:falloff	double	Metres over which shadows fade near their limit; -1 for none.	-1.0		UsdLux
inputs:shadow:falloffGamma	double	The fade's curve.	1.0		UsdLux

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/ShadowAPI": {
      "typeName": "Xform",
      "apiSchemas": ["ShadowAPI"],
      "inputs:shadow:enable": true,
      "inputs:shadow:color": [0.0, 0.0, 0.0],
      "inputs:shadow:distance": -1.0,
      "inputs:shadow:falloff": -1.0,
      "inputs:shadow:falloffGamma": 1.0
    }
  }
}

PhotometricAreaLightAPI

Omniverse's photometric units for shaped lights: lumens, or lux at a distance.

API schema

Attribute	Type	Description	Fallback	Values	Source
photometric:power	double	Luminous flux in lumens, whatever the colour or cone. Authored, it alone sets the light's brightness.	1600.0	≥ 0	Ernie
photometric:illuminance	double	Lux on a surface facing it on its axis at the distance below, in place of the power when both are above 0.	0.0	≥ 0	Ernie
photometric:illuminance:distance	double	Metres at which the illuminance holds; 0 uses the power.	0.0	≥ 0	Ernie

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/PhotometricAreaLightAPI": {
      "typeName": "Xform",
      "apiSchemas": ["PhotometricAreaLightAPI"],
      "photometric:power": 1600.0,
      "photometric:illuminance": 0.0,
      "photometric:illuminance:distance": 0.0
    }
  }
}

PhotometricDistantLightAPI

Omniverse's photometric units for distant lights: lux on a facing surface.

API schema

Attribute	Type	Description	Fallback	Values	Source
photometric:illuminance	double	Lux on a surface facing the light. Authored, it alone sets the light's brightness.	10000.0	≥ 0	Ernie

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/PhotometricDistantLightAPI": {
      "typeName": "Xform",
      "apiSchemas": ["PhotometricDistantLightAPI"],
      "photometric:illuminance": 10000.0
    }
  }
}

PhotometricDomeLightAPI

Omniverse's photometric units for dome lights: lux on an upward-facing surface.

API schema

Attribute	Type	Description	Fallback	Values	Source
photometric:illuminance	double	Lux on an upward-facing surface under the dome. Authored, it alone sets the light's brightness.	10000.0	≥ 0	Ernie

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/PhotometricDomeLightAPI": {
      "typeName": "Xform",
      "apiSchemas": ["PhotometricDomeLightAPI"],
      "photometric:illuminance": 10000.0
    }
  }
}

PhysicalLightIlluminantAPI

Omniverse's illuminant: the shape of a light's spectrum.

API schema

Attribute	Type	Description	Fallback	Values	Source
physical:illuminant	token	The spectrum's shape: white (flat) or blackbody over 380 to 780 nm, illuminant D at the colour temperature, custom (the pairs below), or sun (TSIS-1, 115 nm to 200 um); unset, a black body when the temperature is used, else flat.	""	white, blackbody, illuminant D, custom, sun	Ernie
physical:customIlluminant	float[]	(nm, value) pairs, wavelengths increasing, of a custom illuminant's shape; 0 outside them.	[]		Ernie

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/PhysicalLightIlluminantAPI": {
      "typeName": "Xform",
      "apiSchemas": ["PhysicalLightIlluminantAPI"],
      "physical:customIlluminant": []
    }
  }
}

LaserLight

A laser along -z: a Gaussian beam and its pattern. Its power is ernie:power, its pulses LightAPI's, and its extent the emitter, so framing it frames the device.

Prim type · Inherits BoundableLightBase

Attribute	Type	Description	Fallback	Values	Source
ernie:laser:wavelength	double	Centre wavelength, nm.	532.0	> 0	Ernie
ernie:laser:linewidth	double	Spectral width (FWHM), nm.	0.1	≥ 0	Ernie
ernie:laser:speckle	bool	Grain on rough surfaces, sized by the camera's aperture.	false		Ernie
ernie:laser:waistRadius	double2	1/e^2 radius at the waist along x and y, metres.	[0.0005,0.0005]	> 0	Ernie
ernie:laser:waistDistance	double	Metres from the aperture along the beam to its waist.	0.0		Ernie
ernie:laser:beamQuality	double2	M^2 along x and y: 1 for an ideal beam.	[1.0,1.0]	≥ 1	Ernie
ernie:laser:apertureRadius	double	Metres at which the aperture clips the beam's tails; 0 none.	0.0	≥ 0	Ernie
ernie:laser:pattern	token	The beam itself, a line fanned along x, a grid of beamlets, a field of dots, an image, or a scanned Lissajous figure.	"spot"	spot, line, grid, dots, image, scan	Ernie
ernie:laser:fanAngle	double	A line's full angle along x, degrees.	60.0	> 0, < 170	Ernie
ernie:laser:lineProfile	token	Along a line: flat (a Powell lens) or Gaussian, 1/e^2 at the fan's edges.	"flat"	flat, gaussian	Ernie
ernie:laser:gridColumns	int	A grid's beamlets along x.	5	≥ 1	Ernie
ernie:laser:gridRows	int	A grid's beamlets along y.	5	≥ 1	Ernie
ernie:laser:gridPitch	double2	Degrees between a grid's beamlets along x and y.	[2.0,2.0]	> 0	Ernie
ernie:laser:dotColumns	int	Dots per tile along x.	64	≥ 1	Ernie
ernie:laser:dotRows	int	Dots per tile along y.	48	≥ 1	Ernie
ernie:laser:dotTileColumns	int	Tiles of the same dots along x.	1	≥ 1	Ernie
ernie:laser:dotTileRows	int	Tiles of the same dots along y.	1	≥ 1	Ernie
ernie:laser:dotJitter	double	How far a dot strays from its cell's centre, in cells: 0 a regular grid, 1 anywhere.	0.9	≥ 0, ≤ 1	Ernie
ernie:laser:dotSeed	int	The seed the dots derive from.	1	≥ 0	Ernie
ernie:laser:scanFrequencies	double2	A scan's Lissajous turns along x and y each period, swept faster than cameras see.	[3.0,2.0]	≥ 0	Ernie
ernie:laser:scanPhase	double	A scan's phase along x, degrees.	90.0		Ernie
ernie:laser:efficiency	double	The fraction of the power that goes into the pattern.	1.0	≥ 0, ≤ 1	Ernie
ernie:laser:zeroOrder	double	The fraction of the power left in a beam along the axis.	0.0	≥ 0, ≤ 1	Ernie
ernie:laser:pattern:image	asset	The image pattern's relative power (linear), its top towards +y.	""		Ernie
ernie:laser:pattern:imageArray	float tensor, rank 2	float32 (rows, columns) pattern image in place of the file, on the host or a device.			Ernie
ernie:laser:pattern:fieldOfView	double2	Full angles an image, dots or a scan span along x and y, degrees.	[40.0,30.0]	≥ 0, < 170	Ernie
ernie:laser:sequence:count	int	Patterns shown in turn; 1 for one pattern.	1	≥ 1	Ernie
ernie:laser:sequence:period	double	Seconds each pattern of a sequence shows.	0.03333333333333333	> 0	Ernie
ernie:laser:sequence:delay	double	Seconds on the sensor clock the first pattern shows.	0.0		Ernie

Fallbacks it changes: ernie:power 0.001; ernie:polarization:degree 0.98.

{
  "$schema": "https://alexmaietta.github.io/ernie/schema/ernie-scene.schema.json",
  "prims": {
    "/World/LaserLight": {
      "typeName": "LaserLight",
      "ernie:laser:wavelength": 532.0,
      "ernie:laser:linewidth": 0.1,
      "ernie:laser:speckle": false,
      "ernie:laser:waistRadius": [0.0005, 0.0005],
      "ernie:laser:waistDistance": 0.0,
      "ernie:laser:beamQuality": [1.0, 1.0],
      "ernie:laser:apertureRadius": 0.0,
      "ernie:laser:pattern": "spot",
      "ernie:laser:fanAngle": 60.0,
      "ernie:laser:lineProfile": "flat",
      "ernie:laser:gridColumns": 5,
      "ernie:laser:gridRows": 5,
      "ernie:laser:gridPitch": [2.0, 2.0],
      "ernie:laser:dotColumns": 64,
      "ernie:laser:dotRows": 48,
      "ernie:laser:dotTileColumns": 1,
      "ernie:laser:dotTileRows": 1,
      "ernie:laser:dotJitter": 0.9,
      "ernie:laser:dotSeed": 1,
      "ernie:laser:scanFrequencies": [3.0, 2.0],
      "ernie:laser:scanPhase": 90.0,
      "ernie:laser:efficiency": 1.0,
      "ernie:laser:zeroOrder": 0.0,
      "ernie:laser:pattern:fieldOfView": [40.0, 30.0],
      "ernie:laser:sequence:count": 1,
      "ernie:laser:sequence:period": 0.03333333333333333,
      "ernie:laser:sequence:delay": 0.0
    }
  }
}