Implementation details of the extended input lighting API.

Classes

Name	Description
Enlighten::A8CpuTextureSampler	A8 texture sampler.
Enlighten::AllFilter	Return all light types.
Enlighten::BoxSpotlight	BoxSpotlight class used by extended input lighting.
Enlighten::BoxSpotlight::CachedData	Cached data for box spotlight.
Enlighten::CachedLightSelector	Selects the Cached type for the input light.
Enlighten::CachedLightSelector::Select	Selects the Cached type for the input light.
Enlighten::CachedLightWriter	Cached Lights writer.
Enlighten::CanQuickShade	By default, light types do not support quickshade.
Enlighten::CanQuickShade< LIGHT_TYPE_DIRECTIONAL_LIGHT >	Specialization to enable QuickShade on this light type.
Enlighten::ClusterMaterialComponent	Enlighten internal class for per material dynamic updates.
Enlighten::ClusterMaterials	Enlighten internal implementation for cluster albedo materials.
Enlighten::ClusterMaterials::ClusterMaterialCount	Number of dusters and a material index which is assigned to them.
Enlighten::ClusterProbeBounceSampleData	Precompute data block detailing a buffer of ClusterProbeBounceSamples (internal).
Enlighten::ClusterProbeSample	Cluster probe bounce sample (internal).
Enlighten::ClusterProbeTransparencySampleData	Precompute data block detailing probe transparency sample data (internal).
Enlighten::ConstLightValueIterator	Const LightValue iterator. This contains the logic for iterating over LightValue64 or LightValue128 arrays.
Enlighten::CountLightSizeVisitor	Count light size.
Enlighten::CpuTextureSamplerBase	CPU texture sampler base class.
Enlighten::CullCluster	A class used to apply cluster-light level culling.
Enlighten::CullClusterGroup	A class used to apply clustergroup-light level culling.
Enlighten::CullingIterator	Struct to iterate over the lights of a particular type, applying the culling operation.
Enlighten::CullingIterator< LIGHT_TYPE_INVALID, Culler >	Terminator for CullingIterator.
Enlighten::CullSystem	A class used to apply system-light level culling.
Enlighten::DefaultGeometryTransparencySampler	The default transparency sampler.
Enlighten::DirectionalLight	DirectionalLight class used by extended input lighting.
Enlighten::DirectionalLight::CachedData	Cached data for DirectionalLight.
Enlighten::DynamicMaterialWorkspace	Enlighten object used for dynamic material updates at runtime.
Enlighten::ExcludeQuickShadeFilter	Return all types except quick shade lights.
Enlighten::Fp16CpuTextureSampler	FP16 texture sampler.
Enlighten::FrustumLight	FrustumLight class used by extended input lighting.
Enlighten::FrustumLight::CachedData	Cached data for FrustumLight.
Enlighten::HashLightVisitor	Hash lights functor.
Enlighten::IncidentLightingBuffer	A buffer containing the incident lighting for a system's input sample points (internal).
Enlighten::IndirectInputLightingInternalParameters	A class containing the parameters to be used as input to the internal indirect input lighting stage.
Enlighten::InputLightingBuffer	A single frame of the InputWorkspace lighting (internal).
Enlighten::InputWorkspaceDebugIterator	This class is used to iterate through the duster samples in order to get a InputWorkspaceDebugPoint.
Enlighten::InputWorkspaceDynamicInternal	Runtime data about the quad approximations to clusters used for radiosity computations for dynamic systems (internal).
Enlighten::InputWorkspaceInternal	Runtime data about the dusters (internal).
Enlighten::InternalLightFalloffTable	The light table stores the falloff model of a light.
Enlighten::LightSelector	Selects the input light type.
Enlighten::LightSelector::Select	Selects the input light type.
Enlighten::LightTypeInfo	A class which represents a group of a particular type of lights.
Enlighten::LightValue64	Convenience value type for a half precision lighting value.
Enlighten::LightValueIterator	LightValue iterator. This contains the logic for iterating over LightValue64 or LightValue128 arrays.
Enlighten::LrbCpuTextureSampler	LRB texture sampler.
Enlighten::MaterialAlbedoSampler	Albedo sampler read the cluster albedo after all the quads have been sampled.
Enlighten::MaterialEmissiveSampler	Emissive sampler reads the emissive for the cluster.
Enlighten::MaterialGuids	Storage of mappings between "old" u64 material IDs and "new" instance, mesh and material GUIDs.
Enlighten::MaterialGuids::GeometryInfo	Stored data for a geometry.
Enlighten::MaterialGuids::InstanceInfo	Stored data for an instance.
Enlighten::MaterialGuids::MaterialGuidMapping	Stored data for a material-guid mapping.
Enlighten::MaterialGuids::MeshInfo	Stored data for a mesh.
Enlighten::MaterialSampler	Material sampler reads albedo, emissive and transparency for the cluster.
Enlighten::MaterialTransparencySampler	Transparency sampler reads the transparency for the cluster.
Enlighten::NullGeometryTransparencySampler	A transparency sampler which samples the transparency as opaque.
Enlighten::NullMaterialEmissiveSampler	An emissive material sampler which returns black.
Enlighten::NullMaterialTransparencySampler	A transparency sampler which samples the transparency as opaque.
Enlighten::NullSampler	A base implementation for a sampler that does nothing.
Enlighten::NullSurroundingsSampler	Surroundings sampler that always returns zero.
Enlighten::PackedDusterPoint	This class contains the positions and normals of 4 duster points (internal).
Enlighten::PixelCoord	Enlighten internal class for storing a pixel index within an albedo or emissive texture.
Enlighten::PointLight	PointLight class used by extended input lighting.
Enlighten::PointLight::CachedData	Cached data for point light.
Enlighten::PrecisionHint	Enumeration for the precision hint. The hint is used depending on whether the option is supported on the platform.
Enlighten::ProbeBounceWorkspace	Workspace used for probe bounce (internal).
Enlighten::QuadIterator	Quad iterator class applies the samplers to a set of quads for a given cluster.
Enlighten::QuadShader	The QuadShader class is responsible for unpacking the quad positions and normal during the constructor call and then later it will then iterate through a given set of lights shading the extracted quad.
Enlighten::QuickFlatClusterShader	The QuickFlatClusterShader class is responsible for unpacking a single normal during the constructor call and then later it will then iterate through a given set of lights shading the extracted normal.
Enlighten::QuickQuadShader	The QuickQuadShader class is responsible for unpacking four quad normals during the constructor call and then later it will then iterate through a given set of lights shading the extracted normals.
Enlighten::QuickShadeOnlyFilter	Return only quick shade light types.
Enlighten::R11G11B10CpuTextureSampler	R11G11B10 texture sampler.
Enlighten::R9G9B9E5CpuTextureSampler	R9G9B9E5 texture sampler.
Enlighten::RadiosityInputTree	Compressed description of the input cluster tree.
Enlighten::RectangleLight	RectangleLight class used by extended input lighting.
Enlighten::RectangleLight::CachedData	Cached data for rectangle light.
Enlighten::RgbaCpuTextureSampler	RGBA texture sampler.
Enlighten::RgbmCpuTextureSampler	RGBM texture sampler.
Enlighten::SelectAll	Selector which selects all lights.
Enlighten::SelectCulled	Selector which selects culled lights.
Enlighten::SelectUnculled	Selector which selects unculled lights.
Enlighten::ShadeFourSamplesOperator	Visitor operator used to shade four samples for each light type.
Enlighten::ShadeQuadOperator	Visitor operator used to shade the quad for each light type.
Enlighten::SortedLights	A class used to produce a sorted, culled list of lights.
Enlighten::SortedLightsOperator	Sorted lights operator interface.
Enlighten::SortedLightsVisibilityIdxWriter	Sorted lights visibility index writer.
Enlighten::SortedLightsVisitor	Visitor construct to apply each operator to the relevant light types.
Enlighten::SortedLightsVisitor< LIGHT_TYPE_INVALID, Op, LightTypeFilter >	Terminator condition for light visitor.
Enlighten::Spotlight	Spotlight class used by extended input lighting.
Enlighten::Spotlight::CachedData	Cached data for spotlights.
Enlighten::TransformedBounds	A struct used to apply a transform to a bounding box.
Enlighten::TransparencySurroundingsSampler	Surroundings sampler for transparency.
Enlighten::TransparencyWorkspace	Workspace used for authored destruction of lightmapped geometry (internal).
Enlighten::TypeIdToType	Convert from type enum to concrete type Put this above the light type includes so the specialisations can go in the same file.
Enlighten::TypeIdToType< LIGHT_TYPE_BOXSPOT_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_DIRECTIONAL_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_FRUSTUM_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_POINT_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_RECTANGLE_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_SPOT_LIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_UE4_DIRECTIONAL_LILGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_UE4_ISFALLOFF >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_UE4_RECTLIGHT >	Specialization to convert Light type enumeration to concrete type.
Enlighten::TypeIdToType< LIGHT_TYPE_UE4_UNREALFALLOFF >	Specialization to convert Light type enumeration to concrete type.
Enlighten::VisibilityBuffer	Encapsulation of light visibility information.
Enlighten::VisitLightsGeneric	Visit the lights of a particular type. Do this recursively.
Enlighten::VisitLightsGeneric< TypeSelector, Visitor, LIGHT_TYPE_INVALID >	Visitor terminator.
Enlighten::VisitSelectedLightsGeneric	Visitor for selected lights.
Enlighten::VisitSelectedLightsGeneric< TypeSelector, Visitor, LightSelector, LIGHT_TYPE_INVALID >	Visitor for selected lights.

Variables

Name	Description
const Geo::s32 g_MaxLightDataStackDepth = 6	This is the number of copies of lightcount pointers we have in the LightDataStack member of InputWorkspaceData in the lighting internals.
const Geo::v128 g_VFalloffInvSamples = Geo::VBroadcast(1.0f / (InputLightFalloffTable::g_SampleCount - 2.0f))	Light falloff constants for the function: index = (((samples - 1.0) / (samples - 2.0)) / (1.0 / (samples - 2.0) + d * d);.
const Geo::v128 g_VFalloffNumSamples = Geo::VBroadcast(float(InputLightFalloffTable::g_SampleCount))	Light falloff constants for the function: index = (((samples - 1.0) / (samples - 2.0)) / (1.0 / (samples - 2.0) + d * d);.
const Geo::v128 g_VFalloffSampleFraction = Geo::VBroadcast((InputLightFalloffTable::g_SampleCount - 1.0f) / (InputLightFalloffTable::g_SampleCount - 2.0f))	Light falloff constants for the function: index = (((samples - 1.0) / (samples - 2.0)) / (1.0 / (samples - 2.0) + d * d);.

Typedefs

Name	Description
Geo::v128 LightValue128	Convenience value type for a full precision lighting value.
ClusterMaterialComponent< AlbedoBuffer::ColourType > MaterialAlbedoComponent	Material component for albedo.
ClusterMaterialComponent< EmissiveBuffer::ColourType > MaterialEmissiveComponent	Material component for emissive.
ClusterMaterialComponent< TransparencyBuffer::ColourType > MaterialTransparencyComponent	Material component for transparency.

Functions

Name	Description
CalcLightTableMem(Geo::u32)	Calculate the maximum memory required to hold the lights table.
CalcRequiredScratchSpaceMemoryInternal(InputLightBase **, Geo::u32, Geo::s32)	Calculate how much scratchspace memory will be required by the DoDirectInputLighting() function given the lights to be shaded.
CalculateCoordLinearShiftedByHalfPixel(float, float, Geo::s32, Geo::s32, Geo::s32 &, Geo::s32 &, float &, float &)	Shift by half pixel is needed so that the interpolation code (SampleBilinear) interpolates between correct pixels.
CalculateLightsCachedDataSize(InputLightBase **, Geo::u32)	Calculate the size of the cached lighting data.
CreateSortedLights(InputLightBase , void , Geo::s32, void *, size_t, Geo::u32 &)	Create the buffer of lights sorted by type.
DoDirectInputLightingInternal(DirectInputLightingParameters , void , size_t, TransformOp)	Do the internal direct input lighting stage.
DoIndirectInputLightingInternal(IndirectInputLightingInternalParameters< MaterialSamplerType, InputLightingSurroundingsType, GeometryTransparencySamplerType > *)	Do the internal indirect input lighting stage.
GenerateCachedData(SortedLights , InputLightBase , void **)	Go through all the sorted lights generating the CachedData for each. Also modifies sortedLights to point to the cached data.
GenerateCachedDataGeneric(SortedLights , InputLightBase , void **)	Generate the CacheData for a specific light type.
GenerateCachedDataGeneric< LIGHT_TYPE_INVALID >(SortedLights , InputLightBase , void **)	Specialisation for invalid light types - does nothing.
GetZeroValue()	Helper template to get the zero value of different types.
GetZeroValue< float >()	Helper template to get the zero value of floats.
GetZeroValue< Geo::v128 >()	Helper template to get the zero value of v128s.
LightFalloffFunction(const InternalLightFalloffTable &, const Geo::v128 &, const Geo::v128 &)	common light falloff function used by spot and point lights, computes four lights at a time
operator&(DynamicMaterialWorkspace::Status, DynamicMaterialWorkspace::Status)	Bitwise AND of two dynamic material workspace statuses.
operator\|(DynamicMaterialWorkspace::Status, DynamicMaterialWorkspace::Status)	Bitwise OR of two dynamic material workspace statuses.
operator~(DynamicMaterialWorkspace::Status)	Bitwise NOT of a dynamic material workspace status.
Quantise(const ValueType &)	Quantise the ValueType value based on the ColourType storage.
SampleBilinear(const tIrradianceTexture *, float, float)	Samples the given texture at the given co-ordinates, using bilinear filtering.
SelectAlbedoEmissiveTransparencyAndSurroundings(const IndirectInputLightingParameters , const InputWorkspaceInternal )	Selects albedo, emissive, transparency and surroundings.
SelectEmissiveTransparencyAndSurroundings(const IndirectInputLightingParameters , const InputWorkspaceInternal )	Selects emissive, transparency and surroundings.
SelectSamplersAndDoIndirectInputLighting(const IndirectInputLightingParameters , const InputWorkspaceInternal )	Selects samplers and does indirect input lighting.
SelectSurroundings(const IndirectInputLightingParameters , const InputWorkspaceInternal )	Selects surroundings.
SelectTransparencyAndSurroundings(const IndirectInputLightingParameters , const InputWorkspaceInternal )	Selects transparency and surroundings.
SortedLights(SortedLights *, const Culler &)	Construct from another SortedLights while applying culling.
VisitLights(SortedLights *, Visitor &)	Visitor function to apply the visitor functor to each light.
VisitSelectedLights(const SortedLights , Visitor &, LightSelector &, SortedLightsOperator )	Visits the selected lights with the given visitor.
WriteSortedLightsToMem(SortedLights , void )	Write the sorted lights to memory.

Geo::u32 Enlighten::CalcLightTableMem

public: Geo::u32 CalcLightTableMem
(
Geo::u32 numLights
)

Calculate the maximum memory required to hold the lights table.

Parameters

[in]

numLights

Number of lights in the world

size_t Enlighten::CalcRequiredScratchSpaceMemoryInternal

public: size_t CalcRequiredScratchSpaceMemoryInternal
(
InputLightBase ** lights,
Geo::u32 numLights,
Geo::s32 numLevelsOfCulling
)

Calculate how much scratchspace memory will be required by the DoDirectInputLighting() function given the lights to be shaded.

Parameters

[in]	lights	An array of pointers to input lights.
[in]	numLights	The number of light pointers in the array.
[in]	numLevelsOfCulling	each level of culling requires an additional copy of the SortedLights structure.

Returns

Required memory in bytes

GEO_CONTROLLED_INLINE void Enlighten::CalculateCoordLinearShiftedByHalfPixel

public: GEO_CONTROLLED_INLINE void CalculateCoordLinearShiftedByHalfPixel
(
float u,
float v,
Geo::s32 width,
Geo::s32 height,
Geo::s32 & xi,
Geo::s32 & yi,
float & fracX,
float & fracY
)

Shift by half pixel is needed so that the interpolation code (SampleBilinear) interpolates between correct pixels.

size_t Enlighten::CalculateLightsCachedDataSize

public: size_t CalculateLightsCachedDataSize
(
InputLightBase ** lights,
Geo::u32 numLights
)

Calculate the size of the cached lighting data.

SortedLights* Enlighten::CreateSortedLights

public: SortedLights * CreateSortedLights
(
InputLightBase ** lights,
void ** visibilityPointers,
Geo::s32 numTotalLights,
void * bankScratchspace,
size_t bankScratchspaceSize,
Geo::u32 & requiredLightsBufferSize
)

Create the buffer of lights sorted by type.

Lights banks are controlled through the visibilityPointers parameter.

Parameters

[in]	lights	An unsorted array of pointers to lights
[in]	visibilityPointers	An unsorted array of pointers to visbility buffers. The pointers must correspond to their respective lights in the lights array.
[in]	numTotalLights	The number of entries in the lights and visibilityPointers arrays.
[in]	bankScratchspace	A pointer to memory where the SortedLights buffer will be constructed.
[in]	bankScratchspaceSize	The size of the bankScratchspace memory. (Reserved for future use)
[out]	requiredLightsBufferSize	The size of the buffer required to hold the CachedData objects for the given array of lights.

bool Enlighten::DoDirectInputLightingInternal

public: bool DoDirectInputLightingInternal
(
DirectInputLightingParameters * params,
void * scratchspace,
size_t scratchspaceSize,
TransformOp transform
)

Do the internal direct input lighting stage.

Called from DoDirectInputLighting() function.

Parameters

[in]	params	A pointer to a complete DirectInputLightingParameters object.
[in]	scratchspace	A pointer to allocated scratchspace memory.
[in]	scratchspaceSize	The size of the scratchspace memory calculated with CalcRequiredScratchSpaceMemory function.
[in]	transform	An internal transformation operand.

Returns

true on success

bool Enlighten::DoIndirectInputLightingInternal

public: bool DoIndirectInputLightingInternal
(
IndirectInputLightingInternalParameters< MaterialSamplerType, InputLightingSurroundingsType, GeometryTransparencySamplerType > * params
)

Do the internal indirect input lighting stage.

Called from DoIndirectInputLighting() function.

Parameters

[in]

params

A pointer to a complete IndirectInputLightingParameters object.

Returns

true on success

void* Enlighten::GenerateCachedData

public: void * GenerateCachedData
(
SortedLights * sortedLights,
InputLightBase * cachedLightMemory,
void ** unsortedVisibilityPointers
)

Go through all the sorted lights generating the CachedData for each. Also modifies sortedLights to point to the cached data.

void* Enlighten::GenerateCachedDataGeneric

public: void * GenerateCachedDataGeneric
(
SortedLights * sortedLights,
InputLightBase * cachedLightMemory,
void ** unsortedVisibilityPointers
)

Generate the CacheData for a specific light type.

void* Enlighten::GenerateCachedDataGeneric< LIGHT_TYPE_INVALID >

public: void * GenerateCachedDataGeneric< LIGHT_TYPE_INVALID >
(
SortedLights * sortedLights,
InputLightBase * cachedLightMemory,
void ** unsortedVisibilityPointers
)

Specialisation for invalid light types - does nothing.

ValueType Enlighten::GetZeroValue

public: ValueType GetZeroValue()

Helper template to get the zero value of different types.

float Enlighten::GetZeroValue< float >

public: float GetZeroValue< float >()

Helper template to get the zero value of floats.

Geo::v128 Enlighten::GetZeroValue< Geo::v128 >

public: Geo::v128 GetZeroValue< Geo::v128 >()

Helper template to get the zero value of v128s.

Geo::v128 Enlighten::LightFalloffFunction

public: Geo::v128 LightFalloffFunction
(
const InternalLightFalloffTable & light,
const Geo::v128 & lightRadius,
const Geo::v128 & lightDistances
)

common light falloff function used by spot and point lights, computes four lights at a time

DynamicMaterialWorkspace::Status Enlighten::operator&

public: DynamicMaterialWorkspace::Status operator&
(
DynamicMaterialWorkspace::Status a,
DynamicMaterialWorkspace::Status b
)

Bitwise AND of two dynamic material workspace statuses.

DynamicMaterialWorkspace::Status Enlighten::operator|

public: DynamicMaterialWorkspace::Status operator|
(
DynamicMaterialWorkspace::Status a,
DynamicMaterialWorkspace::Status b
)

Bitwise OR of two dynamic material workspace statuses.

DynamicMaterialWorkspace::Status Enlighten::operator~

public: DynamicMaterialWorkspace::Status operator~
(
DynamicMaterialWorkspace::Status a
)

Bitwise NOT of a dynamic material workspace status.

Enlighten::ClusterMaterialComponent< ColourType >::ValueType Enlighten::ClusterMaterialComponent< ColourType >::Quantise

public: ValueType Quantise
(
const ValueType & val
)

Quantise the ValueType value based on the ColourType storage.

GEO_CONTROLLED_INLINE Geo::v128 Enlighten::SampleBilinear

public: GEO_CONTROLLED_INLINEGeo::v128 SampleBilinear
(
const tIrradianceTexture * texture,
float u,
float v
)

Samples the given texture at the given co-ordinates, using bilinear filtering.

GEO_CONTROLLED_INLINE bool Enlighten::SelectAlbedoEmissiveTransparencyAndSurroundings

public: GEO_CONTROLLED_INLINE bool SelectAlbedoEmissiveTransparencyAndSurroundings
(
const IndirectInputLightingParameters * params,
const InputWorkspaceInternal * inputWorkspace
)

Selects albedo, emissive, transparency and surroundings.

GEO_CONTROLLED_INLINE bool Enlighten::SelectEmissiveTransparencyAndSurroundings

public: GEO_CONTROLLED_INLINE bool SelectEmissiveTransparencyAndSurroundings
(
const IndirectInputLightingParameters * params,
const InputWorkspaceInternal * inputWorkspace
)

Selects emissive, transparency and surroundings.

GEO_CONTROLLED_INLINE bool Enlighten::SelectSamplersAndDoIndirectInputLighting

public: GEO_CONTROLLED_INLINE bool SelectSamplersAndDoIndirectInputLighting
(
const IndirectInputLightingParameters * params,
const InputWorkspaceInternal * inputWorkspace
)

Selects samplers and does indirect input lighting.

GEO_CONTROLLED_INLINE bool Enlighten::SelectSurroundings

public: GEO_CONTROLLED_INLINE bool SelectSurroundings
(
const IndirectInputLightingParameters * params,
const InputWorkspaceInternal * inputWorkspace
)

Selects surroundings.

GEO_CONTROLLED_INLINE bool Enlighten::SelectTransparencyAndSurroundings

public: GEO_CONTROLLED_INLINE bool SelectTransparencyAndSurroundings
(
const IndirectInputLightingParameters * params,
const InputWorkspaceInternal * inputWorkspace
)

Selects transparency and surroundings.

GEO_CONTROLLED_INLINE Enlighten::SortedLights::SortedLights

public: SortedLights
(
SortedLights * sourceLights,
const Culler & culler
)

Construct from another SortedLights while applying culling.

Construct a SortedLights object from another SortedLights object while applying culling.

void Enlighten::VisitLights

public: void VisitLights
(
SortedLights * sortedLights,
Visitor & visitor
)

Visitor function to apply the visitor functor to each light.

void Enlighten::VisitSelectedLights

public: void VisitSelectedLights
(
const SortedLights * sortedLights,
Visitor & visitor,
LightSelector & lightSelector,
SortedLightsOperator * optionalSortedLightsOperator
)

Visits the selected lights with the given visitor.

void Enlighten::WriteSortedLightsToMem

public: void WriteSortedLightsToMem
(
SortedLights * sortedLights,
void * destMem
)

Write the sorted lights to memory.

This will be the buffer that the GPU uses to read lights from.

Parameters

[in]	sortedLights	A valid SortedLights buffer created though a call to CreateSortedLights()
[in]	destMem	A pointer to memory where the CachedData of the sorted lights will be written to.

Browser not supported