module Input Lighting

Operations relating to input lighting generation for the Enlighten runtime.

This is the original input lighting api. Note that there is a new 'extended' input lighting api available on most platforms through EnlightenInputLighting.h.

There is a considerable amount of freedom in how you choose to provide input lighting to Enlighten and the design trade-offs involved can have a huge impact on the success of Enlighten in your product. Most games are unique in some respect, so please feel free to contact Enlighten support for help in choosing the best option for your game.

There are also now two apis for providing input lighting to Enlighten. This one (the original api) and a newer 'extended' input lighting api, available through EnlightenInputLighting.h. They both use the same InputWorkspace structure and have other elements in common, but differ in how the calculation is performed, and the extended api supports additional features.

Enlighten uses a physically realistic algorithm for bouncing indirect light around a scene (subject to the tweakable albedo and bounce scale values), but makes no particular assumptions about the direct lighting model.

In practice, it's often more convenient to use a non-physical fall-off model for spot and point lights. They can be simpler to work with, reduce artefacts, and given the limitations of output displays it's often the only way to produce the desired effect.

Because of this, Enlighten allows users to specify a custom distance fall-off for point and spot light using the Enlighten::InputLightFalloffTable. Now, it is worth emphasising that there needn't be an exact correspondence between the model used for direct, on-screen lighting and the model used for producing input lighting for Enlighten. The closer the two models correspond, the more self-consistent the lighting model as a whole; on the other hand, if the Enlighten input lighting uses a completely non-physical model, it can produce counter-intuitive effects. (One example would be that the amount of light in the scene could vary wildly as a light source of constant intensity is moved closer to or further away from geometry; as soon as the model is non-physical, energy is not necessarily conserved.)

For convenience, Enlighten provides two API functions for generating suitable fall-off tables: Enlighten::GenerateUnrealCompatibleLightFalloffTable(), Enlighten::GenerateUnityCompatibleLightFalloffTable() and Enlighten::GenerateInverseSquaredLightFalloffTable(). See also the Enlighten::InputLight class.

Classes

Variables

Functions

Enums

Typedefs

bool GEO_CALL Enlighten::AddCachedValuesToInputWorkspace

---

public: bool GEO_CALL AddCachedValuesToInputWorkspace
(
    const InputWorkspace * workspaceMemory,
    InputLightingBuffer * output,
    const InputLightingBuffer * cachedValues
)

---

Adds light values from one input lighting buffer to another.

Parameters

bool GEO_CALL Enlighten::AddDusterValuesToInputWorkspace

---

public: bool GEO_CALL AddDusterValuesToInputWorkspace
(
    const InputWorkspace * workspaceMemory,
    InputLightingBuffer * output,
    const Geo::v128 * dusterValues
)

---

Adds light values laid out in a duster block to an Enlighten input workspace.

Parameters

Geo::u32 GEO_CALL Enlighten::CalcInputLightingBufferSize

---

public: Geo::u32GEO_CALL CalcInputLightingBufferSize
(
    const InputWorkspace * inputWorkspace,
    PrecisionHint::Value precisionHint
)

---

Tells you the amount of memory required to hold input lighting for a given system.

Parameters

Returns

Required memory in bytes, 0xFFFFFFFF upon error.

Geo::u32 GEO_CALL Enlighten::CalcLightVisibilitySize

---

public: Geo::u32GEO_CALL CalcLightVisibilitySize
(
    const InputWorkspace * workspaceMemory,
    eLightType lightType
)

---

Determine how much memory is required for a light visibility block.

Directional lights store a byte per cluster, all other lights store a bit per input sample (duster).

Parameters

Returns

Required memory in bytes, 0xFFFFFFFF upon error.

Geo::u32 GEO_CALL Enlighten::CalcLightVisibilitySize

---

public: Geo::u32GEO_CALL CalcLightVisibilitySize
(
    const InputWorkspace * workspaceMemory,
    Enlighten::VisibilityFormat::Type visibilityType
)

---

Determine how much memory is required for a light visibility block.

Directional lights store a byte per cluster, all other lights store a bit per input sample (duster).

Parameters

Returns

Required memory in bytes, 0xFFFFFFFF upon error.

Geo::u32 GEO_CALL Enlighten::CalcPrecomputedVisibilityWorkspaceSize

---

public: Geo::u32GEO_CALL CalcPrecomputedVisibilityWorkspaceSize
(
    const InputWorkspace * workspaceMemory,
    const PrecomputedVisibilityData * precomputedVisibilityData
)

---

Determine how much memory is required for a precomputed visibility workspace.

Parameters

Returns

Required memory in bytes, 0xFFFFFFFF upon error.

bool GEO_CALL Enlighten::ClearInputWorkspace

---

public: bool GEO_CALL ClearInputWorkspace
(
    const InputWorkspace * workspaceMemory,
    InputLightingBuffer * buffer
)

---

Clear the input lighting to black.

This wipes out all bounced light for all previous iterations. Used when "starting over".

Parameters

bool GEO_CALL Enlighten::CompareInputLightingBuffers

---

public: bool GEO_CALL CompareInputLightingBuffers
(
    Geo::Statistics & res,
    const InputLightingBuffer * bufA,
    const InputLightingBuffer * bufB
)

---

Compares Returns true if the lighting buffers could be compared.

Parameters

InputLightingBuffer* GEO_CALL Enlighten::CreateInputLightingBuffer

---

public: InputLightingBuffer *GEO_CALL CreateInputLightingBuffer
(
    void * memory,
    const InputWorkspace * inputWorkspace,
    PrecisionHint::Value precisionHint
)

---

Construct an InputLightingBuffer inside the memory provided.

Parameters

PrecomputedVisibilityWorkspace* GEO_CALL Enlighten::CreatePrecomputedVisibilityWorkspace

---

public: PrecomputedVisibilityWorkspace *GEO_CALL CreatePrecomputedVisibilityWorkspace
(
    void * memory,
    const InputWorkspace * workspaceMemory,
    const PrecomputedVisibilityData * precomputedVisibilityData
)

---

Construct an PrecomputedVisibilityWorkspace inside the memory provided.

Parameters

bool GEO_CALL Enlighten::GenerateInverseSquaredLightFalloffTable

---

public: bool GEO_CALL GenerateInverseSquaredLightFalloffTable
(
    InputLightFalloffTable * lightTable,
    float lightFalloffDistance,
    float lightRadius
)

---

Helper function that generates a Falloff Table using an inverse squared light falloff function, closely approximating real world light falloff.

Light falloff is smoothly biased to zero as it approaches the cutoff.

Parameters

bool GEO_CALL Enlighten::GenerateUnityCompatibleLightFalloffTable

---

public: bool GEO_CALL GenerateUnityCompatibleLightFalloffTable
(
    InputLightFalloffTable * lightTable
)

---

Helper function that generates a falloff table compatible with the Unity light falloff model.

Parameters

bool GEO_CALL Enlighten::GenerateUnrealCompatibleLightFalloffTable

---

public: bool GEO_CALL GenerateUnrealCompatibleLightFalloffTable
(
    InputLightFalloffTable * lightTable,
    float falloffExponent
)

---

Helper function that generates a Falloff Table compatible with the Unreal light falloff model.

Parameters

bool GEO_CALL Enlighten::GetInputLightingBufferLightValue

---

public: bool GEO_CALL GetInputLightingBufferLightValue
(
    const InputLightingBuffer * inputLightingBuffer,
    float lightValue,
    Geo::s32 clusterIdx
)

---

Fill the specified array with the current light value for the given cluster index.

Geo::u32 GEO_CALL Enlighten::GetInputLightingBufferSize

---

public: Geo::u32GEO_CALL GetInputLightingBufferSize
(
    const InputLightingBuffer * inputLightingBuffer
)

---

Returns the size of the specified InputLightingBuffer object.

Parameters

Returns

Required memory in bytes, 0xFFFFFFFF upon error.

Geo::GeoGuid GEO_CALL Enlighten::GetInputLightingBufferSystemId

---

public: Geo::GeoGuidGEO_CALL GetInputLightingBufferSystemId
(
    const Enlighten::InputLightingBuffer * inputLightingBuffer
)

---

Get system id from InputLightingBuffer.

Parameters

bool GEO_CALL Enlighten::GetInputWorkspaceDebugIterator

---

public: bool GEO_CALL GetInputWorkspaceDebugIterator
(
    const InputWorkspace * inputWorkspace,
    Enlighten::InputWorkspaceDebugIterator & debugIterator
)

---

Return a debug iterator object in {debugIterator} which can be used to iterate through the systems debug points.

bool GEO_CALL Enlighten::GetInputWorkspaceDebugPoint

---

public: bool GEO_CALL GetInputWorkspaceDebugPoint
(
    const InputWorkspace * inputWorkspace,
    InputWorkspaceDebugPoint * debugPoint,
    Geo::s32 index
)

---

Fill the specified debug data structure with the current values for the given input workspace sample point.

Does not include lighting.

bool GEO_CALL Enlighten::GetInputWorkspaceLitDebugPoint

---

public: bool GEO_CALL GetInputWorkspaceLitDebugPoint
(
    const InputWorkspace * inputWorkspace,
    InputWorkspaceDebugPoint * debugPoint,
    Geo::s32 index,
    const InputLightingBuffer * lightValues
)

---

Fill the specified debug data structure with the current values for the given input workspace sample point.

Does not include albedo information, as this is part of the various albedo workspaces.

bool GEO_CALL Enlighten::GetInputWorkspaceNormalArray

---

public: bool GEO_CALL GetInputWorkspaceNormalArray
(
    const InputWorkspace * inputWorkspace,
    Geo::v128 * normalsOut
)

---

Fills an array with the normals of all of the input points in an input workspace.

The array should be big enough to hold one vector for each point in the input workspace. The number of points is returned by GetNumberOfPointsInInputWorkspace().

Parameters

bool GEO_CALL Enlighten::GetInputWorkspaceNumPointsPerClusterArray

---

public: bool GEO_CALL GetInputWorkspaceNumPointsPerClusterArray
(
    const InputWorkspace * inputWorkspace,
    Geo::s32 * numPointsPerClusterArray
)

---

Fills the array with the number of points per cluster.

The points inside an input workspace are ordered and grouped by cluster, so you can identify which point belongs it which cluster from this information. You can also produce this information from GetInputWorkspaceDebugPoint() and GetInputWorkspaceLitDebugPoint(), but this implementation would be more efficient.

Parameters

Returns

False on error, true otherwise.

bool GEO_CALL Enlighten::GetInputWorkspacePositionAndNormalArray

---

public: bool GEO_CALL GetInputWorkspacePositionAndNormalArray
(
    const InputWorkspace * inputWorkspace,
    Geo::v128 * positionsOut,
    Geo::v128 * normalsOut
)

---

Fills arrays with the positions and normals of all of the input points in an input workspace.

This array can then be used for visibility computations (eg on the GPU).

Parameters

bool GEO_CALL Enlighten::GetInputWorkspacePositionArray

---

public: bool GEO_CALL GetInputWorkspacePositionArray
(
    const InputWorkspace * inputWorkspace,
    Geo::v128 * positionsOut
)

---

Fills an array with the positions of all of the input points in an input workspace.

This array can then be used for visibility computations (eg on the GPU). The array should be big enough to hold one vector for each point in the input workspace. The number of points is returned by GetNumberOfPointsInInputWorkspace().

Parameters

Geo::u32 GEO_CALL Enlighten::GetInputWorkspaceSize

---

public: Geo::u32GEO_CALL GetInputWorkspaceSize
(
    const InputWorkspace * inputWorkspace
)

---

Returns the size of the specified InputWorkspace object.

Returns

Memory used in bytes, 0xFFFFFFFF upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfClustersInInputWorkspace

---

public: Geo::s32GEO_CALL GetNumberOfClustersInInputWorkspace
(
    const InputWorkspace * inputWorkspace
)

---

Returns the total number of clusters in an input workspace.

Returns

Number of clusters, -1 upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfOutputBuckets

---

public: Geo::s32GEO_CALL GetNumberOfOutputBuckets
(
    const RadSystemCore * radCore
)

---

Returns the total number of output buckets.

Returns

Number of buckets, -1 upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfOutputPixels

---

public: Geo::s32GEO_CALL GetNumberOfOutputPixels
(
    const RadSystemCore * radCore
)

---

Returns the total number of output pixels being lit.

Returns

Number of pixels, -1 upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfOutputPixelsInBucket

---

public: Geo::s32GEO_CALL GetNumberOfOutputPixelsInBucket
(
    const RadSystemCore * radSysCore,
    const Geo::s32 & bucketIdx
)

---

Returns the total number of output pixels in the given bucket.

Returns

Number of pixels in bucket, -1 upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfPointsInInputWorkspace

---

public: Geo::s32GEO_CALL GetNumberOfPointsInInputWorkspace
(
    const InputWorkspace * inputWorkspace
)

---

Returns the total number of sample duster points in an input workspace.

Returns

Number of points, -1 upon error.

Geo::s32 GEO_CALL Enlighten::GetNumberOfTreeClustersInInputWorkspace

---

public: Geo::s32GEO_CALL GetNumberOfTreeClustersInInputWorkspace
(
    const InputWorkspace * inputWorkspace
)

---

Returns the total number of tree clusters in an input workspace.

Returns

Number of tree clusters, -1 upon error.

Geo::u32 GEO_CALL Enlighten::GetPrecomputedVisibilityDataSize

---

public: Geo::u32GEO_CALL GetPrecomputedVisibilityDataSize
(
    const PrecomputedVisibilityData * visibilityData
)

---

Returns the size of the specified PrecomputedVisibilityData object.

Returns

Memory used in bytes, 0xFFFFFFFF upon error.

bool GEO_CALL Enlighten::GetSystemBoundingBox

---

public: bool GEO_CALL GetSystemBoundingBox
(
    const InputWorkspace * inputWorkspace,
    Geo::GeoBoundingBox & bb
)

---

Returns the axis-aligned bounding box of the set of input points in the input workspace.

Parameters

bool GEO_CALL Enlighten::GetSystemBounds

---

public: bool GEO_CALL GetSystemBounds
(
    const InputWorkspace * inputWorkspace,
    Geo::GeoBoundingBox & boundingBox
)

---

Retrieve the bounding volume of the system.

Parameters

bool GEO_CALL Enlighten::SetDirectionalVisibility

---

public: bool GEO_CALL SetDirectionalVisibility
(
    const InputWorkspace * workspaceMemory,
    const PrecomputedVisibilityData * precomputedVisibilityData,
    PrecomputedVisibilityWorkspace * visibilityWorkspace,
    void * visibilityData,
    Geo::v128 lightDirection
)

---

Set visibility in an input workspace for a directional light, using precomputed visibility data.

Parameters

bool GEO_CALL Enlighten::VerifyInputLightingBufferData

---

public: bool GEO_CALL VerifyInputLightingBufferData
(
    const InputLightingBuffer * inputLightingBuffer
)

---

Returns true if there are no NaN's or non-finite numbers in the specified InputLightingBuffer object.

Parameters

bool GEO_CALL Enlighten::WriteInputLightingBuffer

---

public: bool GEO_CALL WriteInputLightingBuffer
(
    const Enlighten::InputLightingBuffer * source,
    Enlighten::InputLightingBuffer * destination
)

---

Overwrite an InputLightingBuffer with another InputLightingBuffer.

Fails if the system ids or sample counts do not match.

Parameters

eLightType

---

public: enum eLightType
{
    LIGHT_TYPE_INVALID = -1,
    LIGHT_TYPE_SPOT_LIGHT = 0,
    LIGHT_TYPE_POINT_LIGHT = 1,
    LIGHT_TYPE_DIRECTIONAL_LIGHT = 2,
    LIGHT_TYPE_RECTANGLE_LIGHT = 3,
    LIGHT_TYPE_FRUSTUM_LIGHT = 4,
    LIGHT_TYPE_BOXSPOT_LIGHT = 5,
    LIGHT_TYPE_NUM_TYPES
}

---

Different types of Enlighten input lights.

enumerators