RixShadingContext is analogous to a RenderMan grid - it is a group of 1 or more points that may be shaded. More...

#include <RixShading.h>

Classes
class	Allocator
	Allocator is a utility (fully inlined) class to assist with tedious memory pool allocations. More...

struct	Id
	shadingCtxId is a unique identifier for this shading context. More...

Public Types
enum	BuiltinVolume { k_SSDiffusion, k_SSPathTraced }
	BuiltinVolumes are "preloaded" and initialized by the renderer. More...

enum	BuiltinBxdf { k_NullBxdf }
	BuiltinBxdfs can be constructed cheaply and offer a basic set of capabilities. More...

enum	BuiltinVar { k_P = 0, k_PRadius, k_Po, k_Nn, k_Ngn, k_Non, k_Tn, k_Vn, k_VLen, k_curvature, k_incidentRaySpread, k_incidentRayRadius, k_incidentLobeSampled, k_mpSize, k_biasR, k_biasT, k_geomShadowTermBias, k_u, k_v, k_w, k_du, k_dufp = k_du, k_dv, k_dvfp = k_dv, k_dw, k_dwfp = k_dw, k_dPdu, k_dPdv, k_dPdw, k_dPdtime, k_time, k_Id, k_Id2, k_outsideIOR, k_Oi, k_lpeState, k_launchShadingCtxId, k_motionFore, k_motionBack, k_curvatureU, k_curvatureV, k_dPcameradtime, k_wavelength, k_Naon, k_numBuiltinVars }

enum	TransformInterpretation { k_AsPoints, k_AsVectors, k_AsNormals }

enum	MemCategory { k_BxdfMem, k_PatternMem }

Public Member Functions
bool	HasHits () const

bool	HasMisses () const

RixBxdf *	GetBxdf () const

RixOpacity *	GetOpacity () const

RixDisplacement *	GetDisplacement () const

RixVolumeIntegrator *	GetSubsurface () const

RixVolumeIntegrator *	GetVolume () const

RixPostLighting *	GetPostLighting () const

virtual bool	HasSubsurface () const =0

virtual RixVolumeIntegrator *	BeginSubsurface (int numRays, RtRayGeometry *rays) const =0

virtual void	EndSubsurface (RixVolumeIntegrator *) const =0

virtual bool	HasVolume (RixSCVolumeSelector) const =0
	Support for volume integration: More...

virtual RixVolumeIntegrator *	BeginVolume (RixSCVolumeSelector, int numRays, RtRayGeometry *rays) const =0

virtual void	EndVolume (RixVolumeIntegrator *) const =0

RixVolumeIntegrator *	BeginIncidentVol (int numRays, RtRayGeometry *rays) const
	two convenience methods More...

RixVolumeIntegrator *	BeginOppositeVol (int numRays, RtRayGeometry *rays) const

virtual std::vector< const RixShadingContext * > const *	GetOverlappingVolumes () const =0
	Returns a list of shading contexts associated with any overlapping volumes. More...

virtual RixVolumeIntegrator *	GetBuiltinVolume (BuiltinVolume builtin, RixBxdfFactory factory, void instanceData) const =0

virtual void	SetupRngCtxForPattern () const =0

virtual RixBxdf *	GetBuiltinBxdf (BuiltinBxdf, RixBxdfFactory *) const =0

virtual RixDisplayServices *	GetDisplayServices (int version=1) const =0
	Get access to the display services. More...

virtual void	GetBuiltinVar (BuiltinVar, int const **var) const =0

virtual void	GetBuiltinVar (BuiltinVar, float const **var) const =0

virtual void	GetBuiltinVar (BuiltinVar, RtFloat3 const **var) const =0

virtual void	GetBuiltinVar (BuiltinVar, RixLPEState const *var) const =0

virtual void	SetBuiltinVar (BuiltinVar, float *var)=0
	SetBuiltinVar() allows the values of any builtin variable to be overridden. More...

virtual void	SetBuiltinVar (BuiltinVar, RtFloat3 *var)=0

virtual RixSCDetail	GetPrimVar (const RtUString name, RixSCType type, int arraylen) const =0
	GetPrimVar: lazily evaluates the named primitive variable. More...

virtual RixSCDetail	GetPrimVar (const RtUString name, float fill, float const var, float const radius=NULL) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, RtFloat2 fill, RtFloat2 const var, float const radius=NULL) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, RtFloat3 fill, RtFloat3 const var, float const radius=NULL) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, RtUString const **var) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, RtMatrix4x4 const &fill, RtMatrix4x4 const **var) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, float const var, float const dXdu, float const **dXdv) const =0
	This variant of GetPrimVar produces uni/bi/trivariate derivatives of an arbitrary primvar across the surface measured with respect to u and v. More...

virtual RixSCDetail	GetPrimVar (const RtUString name, RtFloat2 const var, float const dXdu, float const dYdu, float const dXdv, float const **dYdv) const =0

virtual RixSCDetail	GetPrimVar (const RtUString name, RtFloat3 const var, float const dXdu, float const dYdu, float const dZdu, float const dXdv, float const dYdv, float const **dZdv) const =0

virtual void	SetPrimVar (const RtUString name, RixSCDetail d, float var, float radius)=0
	SetPrimVar: useful for changing state on mutable shading contexts for consumption by upstream pattern-graph nodes. More...

virtual void	SetPrimVar (const RtUString name, RixSCDetail d, RtFloat2 var, float radius)=0

virtual void	SetPrimVar (const RtUString name, RixSCDetail d, RtFloat3 var, float radius)=0

virtual void	SetPrimVar (const RtUString name, RixSCDetail d, RtUString *var)=0

virtual void	SetPrimVar (const RtUString name, RixSCDetail d, RtMatrix4x4 *var)=0

virtual bool	GetProperty (RayProperty, void const *) const
	As long as the RixIntegrator used supports the appropriate ray property query, shading plugin authors may want to query ray properties such as the ray depth or eye throughput, in order to allow for artistic control or optimization. More...

virtual bool	SetProperty (RayProperty, void const *) const

virtual int	Transform (TransformInterpretation interp, const RtUString fromSpace, const RtUString toSpace, RtFloat3 var, float radius=NULL) const =0
	Transform an array of RtFloat3 (and optional radius) the same size as the numPts in the RixShadingContext. More...

virtual int	GetTransform (const RtUString fromSpace, const RtUString toSpace, RtMatrix4x4 const *matrix, int numMatrices) const =0
	Return an array of matrices numPts in size that represents the transformation from "fromSpace" to "toSpace". More...

virtual RixShadingContext *	CreateMutableContext () const =0
	Create a context that can be mutated (implements SetBuiltinVar) for the purposes of super sampling a pattern network. More...

virtual RixShadingContext const *	GetPrimaryContext () const =0
	GetPrimaryContext returns a reference to the (immutable) primary shading context. More...

virtual RixIntegratorContext *	GetIntegratorContext () const =0
	Returns a reference to the RixIntegratorContext which created this shading context. More...

virtual RixShadingContext const *	GetContextById (RixShadingContext::Id sCtxId) const =0
	GetShadingContextById, given a RixShadingContext::Id, returns a reference to the shading context which has a matching Id, or NULL if no such context can be found. More...

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, int const *result, int const dflt=NULL, bool promoteToVarying=false) const =0
	EvalParam. More...

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, float const *result, float const dflt=NULL, bool promoteToVarying=false) const =0

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, RtColorRGB const *result, RtColorRGB const dflt=NULL, bool promoteToVarying=false) const =0

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, RtFloat3 const *result, RtFloat3 const dflt=NULL, bool promoteToVarying=false) const =0

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, RtMatrix4x4 const *result, RtMatrix4x4 const dflt=NULL, bool promoteToVarying=false) const =0

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, RtUString const *result, RtUString const dflt=NULL, bool promoteToVarying=false) const =0

virtual RixSCDetail	EvalParam (int paramId, int arrayIndex, RixBxdfFactory *result, RixBxdfFactory dflt=NULL, bool promoteToVarying=false) const =0

template<class T >
RixSCDetail	EvalAndCopyParam (int paramId, int arrayIndex, T *result, T const dflt=NULL, bool promoteToVarying=false, MemCategory mcat=k_BxdfMem) const
	EvalAndCopyParam: Templated convenience routine for callers who need to modify input parameters. More...

virtual int	GetParamId (const RtUString name, int *paramId) const =0
	GetParamId maps a string name to a more efficient integer reference. More...

virtual int	GetParamInfo (int paramId, RixSCType type, RixSCConnectionInfo cInfo, int *arrayLength=NULL) const =0
	GetParamInfo returns additional detail about the parameter such as its connection status, type, and array length. More...

int	GetParamInfo (int paramId, RixSCType type, bool isConnected, int *arrayLength=NULL) const
	This version of GetParamInfo is a convenience for use-cases where a bool notion of connection is sufficient. More...

virtual void	GetNearestHits (int numRays, RtRayGeometry const rays, RtHitPoint hits, const RtUString subset=US_NULL, const RtUString excludeSubset=US_NULL, RtHitSides hitSides=k_SidesBoth) const =0
	GetNearestHits: traces rays to determine the nearest hit in the given direction. More...

virtual bool	GetLightEmission (RtColorRGB emission, int lightGroupIds=NULL) const =0
	GetLightEmission: returns the sampled emission associated with the shading points. More...

virtual void *	Allocate (size_t n, size_t size, MemCategory m) const =0
	Allocate: fast memory allocation support from a memory pool tailored to Pattern and Bxdf plugins. More...

template<class T >
T *	New (size_t nObjs, MemCategory cat=k_BxdfMem) const
	New is a utility (fully inlined) non-virtual method to assist with tedious memory allocation tasks. More...

virtual RixInterface *	GetRixInterface (RixInterfaceId id) const =0
	Get the specified interface from this context. More...

Public Attributes
struct RixShadingContext::Id	shadingCtxId

int	numPts
	numPts is the number of shading points. More...

struct {
unsigned eyePath: 1

unsigned lightPath: 1
	true if shading for an eye path More...

unsigned primaryHit: 1
	true if shading for a light path More...

unsigned missContext: 1
	true if shading for a first hit More...

unsigned reyesGrid: 1
	true if this context represents misses More...

RixSCShadingMode shadingMode
	true if we're operating on a reyes grid this may occur in a variety of caching conditions More...

RixBxdf * bxdf
	The bxdf shader is non-NULL for radiance queries and is responsible for computing light scattering. More...

RixOpacity * opacity

RixDisplacement * displacement

RixVolumeIntegrator * subsurface

RixVolumeIntegrator * volume

RixPostLighting * postlighting

}	scTraits
	shadingCtxTraits conveys a variety of (uniform) ShadingContex traits to shader and integrator. More...

int *	integratorCtxIndex
	integratorCtxIndex maps indices to varying ShadingContext entries to the index associated with IntegratorContext. More...

int *	rayId
	rayId is similar to integratorCtxIndex. More...

RtColorRGB *	transmission
	transmission is a per-point transmission that is associated with the ray that produced the associated hit. More...

RtColorRGB *	matteTransmission
	Similar to transmission but restricted to the transmittance computed solely from matte or holdout volumes. More...

RtColorRGB *	pointWeight
	If the shading context was created via an importance sampling method, this is the associated weight the integrator needs to multiply in. More...

int *	pointSampleCount
	If multiple volume samples are taken for multi scattering, the integrator needs to multiply this value in for thruput. More...

RtColorRGB *	opacityThroughput

RtColorRGB *	opacity

float *	opacityStochasticWeight

void *	lightingServicesData
	lightingServicesData is a blind pointer private RixLightingServices data More...

RixLight const *	light

RixRNG *	m_rngCtx

Protected Member Functions
	~RixShadingContext () override

virtual RixShadingContext *	BeginVolumeSampling () const =0

virtual RixShadingContext const *	EndVolumeSampling (const RixShadingContext , RixBXLobeTraits const exposeVol=NULL, int const *membership=NULL) const =0

Protected Attributes
RixRNG::SampleCtx *	m_rngSampleCtx

Friends
class	RixVolumeIntegrator

class	LightVertexCache

Detailed Description

RixShadingContext is analogous to a RenderMan grid - it is a group of 1 or more points that may be shaded.

The group of points usually arrive through ray traced "hits". In this case, the shading context provides geometric details through its GetPrimVar and GetBuiltinVar methods. Associated with each primvar is a varying filter size that is computed as a function of rendering conditions such as shading rate and ray differentials. The incoming positions are not guaranteed to be neighbors and so do not support requirements for computing first-differences. Rather, differential information is embodied through filter radii and these are only computable for known builtin and primitive variables.

ShadingContexts can also be produced by ray traced "misses". Now only the ray origination information is available and the class of shading activities is limited to cases where no bxdf, builtin and primitive variables are required. RixShadingContexts are comprised exclusively of hits or misses and optionally delivered across the RixIntegratorContext's GetNearestHits method.

ShadingContexts operate in a small number of modes according to the integration requirements.

Member Enumeration Documentation

◆ BuiltinBxdf

enum RixShadingContext::BuiltinBxdf

BuiltinBxdfs can be constructed cheaply and offer a basic set of capabilities.

They differ from Bxdf plugins in that they expose no parameters and thus no BxdfFactories are required.

Enumerator
k_NullBxdf

◆ BuiltinVar

enum RixShadingContext::BuiltinVar

Enumerator
k_P	Shading position (type RtFloat3)
k_PRadius	When raytracing, the ray footprint radius at P, otherwise the micropolygon radius (ie half mpSize) at P (type float)
k_Po	Undisplaced P (type RtFloat3)
k_Nn	Normalized shading normal (type RtFloat3)
k_Ngn	Normalized geometric normal (type RtFloat3)
k_Non	Normalized undisplaced N (type RtFloat3)
k_Tn	Normalized shading tangent (type RtFloat3)
k_Vn	Normalized view vector, points away from shading points (type RtFloat3)
k_VLen	Length of view vector (type float)
k_curvature	Local mean surface curvature (type float)
k_incidentRaySpread	Spread of incident ray (type float): how much the ray radius increased for each unit distance the ray travelled.
k_incidentRayRadius	Radius of incident ray at P (type float)
k_incidentLobeSampled	RixBXLobeSampled id of incident rays (type int)
k_mpSize	Micropolygon size; 0 for non-tessellated surfaces (type float)
k_biasR	Bias to apply for reflected rays (type float)
k_biasT	Bias to apply for transmitted rays (type float)
k_geomShadowTermBias	Bias to apply for shadow rays (Direct Light) to avoid the geometric shadow terminator.
k_u	Surface U parameterization (type float)
k_v	Surface V parameterization (type float)
k_w	Surface W parameterization (type float)
k_du	Ray footprint (radius) in U (type float)
k_dufp
k_dv	Ray footprint (radius) in V (type float)
k_dvfp
k_dw	Ray footprint (radius) in W (type float)
k_dwfp
k_dPdu	Surface derivative in U (type RtFloat3)
k_dPdv	Surface derivative in V (type RtFloat3)
k_dPdw	Surface derivative in W (type RtFloat3)
k_dPdtime	Instantaneous P velocity relative to the world (type RtFloat3)
k_time	Shading time, normalized between shutter open and close (type float)
k_Id	Attribute "identifier" "id" (type int)
k_Id2	Attribute "identifier" "id2" (type int)
k_outsideIOR	Incident index of refraction (type float)
k_Oi	Opacity (type RtFloat3)
k_lpeState	Current LPE State (type RixLPEState)
k_launchShadingCtxId	Parent ray shading context serialization (type int)
k_motionFore	Forward 2D raster-space motion vector (type RtFloat3)
k_motionBack	Backward 2D raster-space motion vector (type RtFloat3)
k_curvatureU	Local principal surface curvature in u dir (type float)
k_curvatureV	Local principal surface curvature in v dir (type float)
k_dPcameradtime	Instantaneous P velocity relative to the camera (type RtFloat3)
k_wavelength	Wavelength of incident ray (type float): 380-780nm visible spectrum.
k_Naon	Normalized analytical undisplaced N (type RtFloat3)
k_numBuiltinVars

◆ BuiltinVolume

enum RixShadingContext::BuiltinVolume

BuiltinVolumes are "preloaded" and initialized by the renderer.

Plugin volumes are usually "compiled-in" to the associated Bxdf. In both cases, the Bxdf's BeginInterior method is invoked to instantiate a VolumeIntegrator object.

Enumerator
k_SSDiffusion
k_SSPathTraced

◆ MemCategory

enum RixShadingContext::MemCategory

Enumerator
k_BxdfMem
k_PatternMem

◆ TransformInterpretation

enum RixShadingContext::TransformInterpretation

Enumerator
k_AsPoints
k_AsVectors
k_AsNormals

Constructor & Destructor Documentation

◆ ~RixShadingContext()

RixShadingContext::~RixShadingContext ( )

inlineoverrideprotected

Member Function Documentation

◆ Allocate()

virtual void* RixShadingContext::Allocate	(	size_t	n,
		size_t	size,
		MemCategory	m
	)		const

pure virtual

Allocate: fast memory allocation support from a memory pool tailored to Pattern and Bxdf plugins.

Memory allocated via this interface is managed (freed) by RixShadingContext according to the lifetime requirements of the associated MemCategory. As with many custom memory allocation schemes, clients should use "placement new" and not rely on invocation of a destructor. RixAlloca can be used for intra-procedure dynamic memory allocation.

Referenced by RixShadingContext::Allocator::Allocate(), RixShadingContext::Allocator::AllocFor(), RixShadingContext::Allocator::AllocForBxdf(), RixShadingContext::Allocator::AllocForPattern(), RixShadingContext::Allocator::AllocForVolume(), EvalAndCopyParam(), and New().

◆ BeginIncidentVol()

RixVolumeIntegrator* RixShadingContext::BeginIncidentVol	(	int	numRays,
		RtRayGeometry *	rays
	)		const

inline

two convenience methods

References BeginVolume(), and k_RixSCIncidentVolume.

◆ BeginOppositeVol()

RixVolumeIntegrator* RixShadingContext::BeginOppositeVol	(	int	numRays,
		RtRayGeometry *	rays
	)		const

inline

References BeginVolume(), and k_RixSCOppositeVolume.

◆ BeginSubsurface()

virtual RixVolumeIntegrator* RixShadingContext::BeginSubsurface	(	int	numRays,
		RtRayGeometry *	rays
	)		const

pure virtual

◆ BeginVolume()

virtual RixVolumeIntegrator* RixShadingContext::BeginVolume	(	RixSCVolumeSelector	,
		int	numRays,
		RtRayGeometry *	rays
	)		const

pure virtual

Referenced by BeginIncidentVol(), and BeginOppositeVol().

◆ BeginVolumeSampling()

virtual RixShadingContext* RixShadingContext::BeginVolumeSampling ( ) const

protectedpure virtual

Referenced by RixVolumeIntegrator::BeginVolumeSampling().

◆ CreateMutableContext()

virtual RixShadingContext* RixShadingContext::CreateMutableContext ( ) const

pure virtual

Create a context that can be mutated (implements SetBuiltinVar) for the purposes of super sampling a pattern network.

The mutable context is created in the Bxdf memory of its parent context and does not need to be released. It will be automatically reclaimed when its parent context is released.

◆ EndSubsurface()

virtual void RixShadingContext::EndSubsurface ( RixVolumeIntegrator * ) const

pure virtual

◆ EndVolume()

virtual void RixShadingContext::EndVolume ( RixVolumeIntegrator * ) const

pure virtual

◆ EndVolumeSampling()

virtual RixShadingContext const* RixShadingContext::EndVolumeSampling	(	const RixShadingContext *	,
		RixBXLobeTraits const *	exposeVol = `NULL`,
		int const *	membership = `NULL`
	)		const

protectedpure virtual

Referenced by RixVolumeIntegrator::EndVolumeSampling().

◆ EvalAndCopyParam()

template<class T >

RixSCDetail RixShadingContext::EvalAndCopyParam	(	int	paramId,
		int	arrayIndex,
		T **	result,
		T const *	dflt = `NULL`,
		bool	promoteToVarying = `false`,
		MemCategory	mcat = `k_BxdfMem`
	)		const

inline

EvalAndCopyParam: Templated convenience routine for callers who need to modify input parameters.

Use with care as it incurs an additional memory allocation and memcpy. NB: only a subset of types produce meaningfully writable results. RtUStrings, RixBxdfFactory are not among them.

References Allocate(), EvalParam(), k_RixSCUniform, and k_RixSCVarying.

◆ EvalParam() [1/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		int const **	result,
		int const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

EvalParam.

Id-based parameter evaluation captures the data flow through graph of connected RixPattern and RixBxdf nodes.

A parameter can be constant or computed. Calls to the Eval method of non-constant parameters may trigger function evaluation. Parameter values may be cached by the renderer for the duration of an execution context (see RixBxdf Begin/End).

Calls to EvalParam must fill an entire ShadingContext of values. The exception to this rule is for RixBxdf composition where a RixBxdf may be obtained. In that case, the 'driver' Bxdf is expected to distribute Begin/Eval/Generate/End messages to subservient Bxdf instances.

Parameter evaluation: Bxdfs and Patterns invoke EvalParam to sample their inputs. Since inputs may or may not obtain values from upstream, the detail, obtained via GetParamInfo, can be consulted to hoist expensive computations out of per-point loops. Again, caller is expected to know the type of its parameters. If the optional EvalParam parameter, promoteToVarying is true, then the detail of the result is guaranteed to be k_RixSCVarying but the returned detail will be that associated with the actual connection state. EvalParam works for array elements as well as simple parameters. In the simple-case, set arrayIndex to -1. Result is const and should usually not be overwritten by by caller.. It's common for Bxdf's to wish to conform (clamp) their inputs to reasonable ranges and this can be done only in bxdf nodes and only by const_cast-ing. If a value can't be obtained via the network nor the Ri parameterlist, we fill the result with the default value provided. If the default value isn't provided we return RixSCInvalidDetail.

Referenced by EvalAndCopyParam(), RixShadingParam::InitEvalC(), RixShadingParam::InitEvalF(), RixShadingParam::InitEvalI(), and RixShadingParam::InitEvalV().

◆ EvalParam() [2/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		float const **	result,
		float const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ EvalParam() [3/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		RtColorRGB const **	result,
		RtColorRGB const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ EvalParam() [4/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		RtFloat3 const **	result,
		RtFloat3 const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ EvalParam() [5/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		RtMatrix4x4 const **	result,
		RtMatrix4x4 const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ EvalParam() [6/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		RtUString const **	result,
		RtUString const *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ EvalParam() [7/7]

virtual RixSCDetail RixShadingContext::EvalParam	(	int	paramId,
		int	arrayIndex,
		RixBxdfFactory **	result,
		RixBxdfFactory *	dflt = `NULL`,
		bool	promoteToVarying = `false`
	)		const

pure virtual

◆ GetBuiltinBxdf()

virtual RixBxdf* RixShadingContext::GetBuiltinBxdf	(	BuiltinBxdf	,
		RixBxdfFactory *
	)		const

pure virtual

◆ GetBuiltinVar() [1/4]

virtual void RixShadingContext::GetBuiltinVar	(	BuiltinVar	,
		int const **	var
	)		const

pure virtual

Referenced by RixIntegrator::IntegrateRays(), RixBump(), RixFresnelDielectric(), RixShiftCtxInU(), and RixShiftCtxInV().

◆ GetBuiltinVar() [2/4]

virtual void RixShadingContext::GetBuiltinVar	(	BuiltinVar	,
		float const **	var
	)		const

pure virtual

◆ GetBuiltinVar() [3/4]

virtual void RixShadingContext::GetBuiltinVar	(	BuiltinVar	,
		RtFloat3 const **	var
	)		const

pure virtual

◆ GetBuiltinVar() [4/4]

virtual void RixShadingContext::GetBuiltinVar	(	BuiltinVar	,
		RixLPEState const *	var
	)		const

pure virtual

◆ GetBuiltinVolume()

virtual RixVolumeIntegrator* RixShadingContext::GetBuiltinVolume	(	BuiltinVolume	builtin,
		RixBxdfFactory *	factory,
		void *	instanceData
	)		const

pure virtual

◆ GetBxdf()

RixBxdf* RixShadingContext::GetBxdf ( ) const

inline

References k_RixSCBakeIntegratorQuery, k_RixSCBakePatternQuery, k_RixSCScatterQuery, k_RixSCVolumeScatterQuery, k_RixSCVolumeTransmissionQuery, and scTraits.

Referenced by PxrGeoAOV::Splat().

◆ GetContextById()

virtual RixShadingContext const* RixShadingContext::GetContextById ( RixShadingContext::Id sCtxId ) const

pure virtual

GetShadingContextById, given a RixShadingContext::Id, returns a reference to the shading context which has a matching Id, or NULL if no such context can be found.

It is the responsibility of the integrator and the caller to ensure that the shading context has not been returned to the system via RixIntegratorContext::ReleaseShadingContexts.

◆ GetDisplacement()

RixDisplacement* RixShadingContext::GetDisplacement ( ) const

inline

References k_RixSCDisplacementQuery, and scTraits.

◆ GetDisplayServices()

virtual RixDisplayServices* RixShadingContext::GetDisplayServices ( int version = 1 ) const

pure virtual

Get access to the display services.

This is the same display service normally offered by the integrator context but is provided here to allow RixPatterns and RixBXDFs to bypass the integrator and write directly into AOV channels for special effects.

◆ GetIntegratorContext()

virtual RixIntegratorContext* RixShadingContext::GetIntegratorContext ( ) const

pure virtual

Returns a reference to the RixIntegratorContext which created this shading context.

◆ GetLightEmission()

virtual bool RixShadingContext::GetLightEmission	(	RtColorRGB *	emission,
		int *	lightGroupIds = `NULL`
	)		const

pure virtual

GetLightEmission: returns the sampled emission associated with the shading points.

Nonzero return values are only expected if the shading context is asssociated with a direct light source. This should not be confused with the results of the LocalEmission of a Bxdf, but might overlap as with PxrLightEmission.

◆ GetNearestHits()

virtual void RixShadingContext::GetNearestHits	(	int	numRays,
		RtRayGeometry const *	rays,
		RtHitPoint *	hits,
		const RtUString	subset = `US_NULL`,
		const RtUString	excludeSubset = `US_NULL`,
		RtHitSides	hitSides = `k_SidesBoth`
	)		const

pure virtual

GetNearestHits: traces rays to determine the nearest hit in the given direction.

Both arrays must be at least numRays long. Misses are indicated in the RtHitPoint via hits[i].dist == 0. An optional trace subset can be provided to further constrain objects considered. Clients should include RixIntegrator.h for the definition of RtRayGeometry and RtHitPoint structs.

Parameters

[in]	numRays	Number of rays to trace. Cannot be larger than RixIntegratorContext::k_MaxRaysPerBatch.
[in]	rays	The rays to trace. Array of size `numRays`.
[out]	hits	Resulting ray hits from tracing rays.
[in]	subset	The method will only yield hits on objects whose group membership matches `subset`.
[in]	excludeSubset	The method will ignore hits on objects whose group membership matches `excludeSubset`.
[in]	hitSides	The method will only yields hits on the indicated side of objects.

◆ GetOpacity()

RixOpacity* RixShadingContext::GetOpacity ( ) const

inline

References k_RixSCOpacityQuery, k_RixSCPresenceQuery, k_RixSCVolumeTransmissionQuery, and scTraits.

◆ GetOverlappingVolumes()

virtual std::vector<const RixShadingContext*> const* RixShadingContext::GetOverlappingVolumes ( ) const

pure virtual

Returns a list of shading contexts associated with any overlapping volumes.

◆ GetParamId()

virtual int RixShadingContext::GetParamId	(	const RtUString	name,
		int *	paramId
	)		const

pure virtual

GetParamId maps a string name to a more efficient integer reference.

The paramId may be negative to support dynamic inputs. Non-negative values are indices into the parameter table, while negative values are interpretted as indices into the parameterlist of a RIB instance. Returns 0 on success, returns nonzero if named parameter is not found.

◆ GetParamInfo() [1/2]

virtual int RixShadingContext::GetParamInfo	(	int	paramId,
		RixSCType *	type,
		RixSCConnectionInfo *	cInfo,
		int *	arrayLength = `NULL`
	)		const

pure virtual

GetParamInfo returns additional detail about the parameter such as its connection status, type, and array length.

Its primary use is during pattern-graph execution to determine connectivity or dynamic array sizes. Returns 0 on success, nonzero on failure.

Referenced by GetParamInfo().

◆ GetParamInfo() [2/2]

int RixShadingContext::GetParamInfo	(	int	paramId,
		RixSCType *	type,
		bool *	isConnected,
		int *	arrayLength = `NULL`
	)		const

inline

This version of GetParamInfo is a convenience for use-cases where a bool notion of connection is sufficient.

References GetParamInfo(), and k_RixSCNetworkValue.

◆ GetPostLighting()

RixPostLighting* RixShadingContext::GetPostLighting ( ) const

inline

References k_RixSCBakeIntegratorQuery, k_RixSCBakeQuery, k_RixSCScatterQuery, k_RixSCVolumeScatterQuery, and scTraits.

◆ GetPrimaryContext()

virtual RixShadingContext const* RixShadingContext::GetPrimaryContext ( ) const

pure virtual

GetPrimaryContext returns a reference to the (immutable) primary shading context.

Only in a case where the caller is operating on a mutable context created by a downstream node should the returned value differ from the invoking ShadingContext.

◆ GetPrimVar() [1/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RixSCType *	type,
		int *	arraylen
	)		const

pure virtual

GetPrimVar: lazily evaluates the named primitive variable.

Caller is expected to know the datatype in advance and invoke the correct variant. The first variant can be used to efficiently query the existence, type and arrayLength of an primvar. The optional radius parameter is filled with an approximate isotropic filter radius associated with the projected ray differentials of each shading point. If the primvar cannot be found, the return value is initialized with the fill value and the return value is k_RixSCInvalidDetail.

Referenced by RixBump().

◆ GetPrimVar() [2/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		float	fill,
		float const **	var,
		float const **	radius = `NULL`
	)		const

pure virtual

◆ GetPrimVar() [3/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtFloat2	fill,
		RtFloat2 const **	var,
		float const **	radius = `NULL`
	)		const

pure virtual

◆ GetPrimVar() [4/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtFloat3	fill,
		RtFloat3 const **	var,
		float const **	radius = `NULL`
	)		const

pure virtual

◆ GetPrimVar() [5/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtUString const **	var
	)		const

pure virtual

◆ GetPrimVar() [6/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtMatrix4x4 const &	fill,
		RtMatrix4x4 const **	var
	)		const

pure virtual

◆ GetPrimVar() [7/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		float const **	var,
		float const **	dXdu,
		float const **	dXdv
	)		const

pure virtual

This variant of GetPrimVar produces uni/bi/trivariate derivatives of an arbitrary primvar across the surface measured with respect to u and v.

This function is useful in unusual geometric supersampling conditions and for bump mapping. The simpler variant is preferred over this method unless the special features are required.

◆ GetPrimVar() [8/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtFloat2 const **	var,
		float const **	dXdu,
		float const **	dYdu,
		float const **	dXdv,
		float const **	dYdv
	)		const

pure virtual

◆ GetPrimVar() [9/9]

virtual RixSCDetail RixShadingContext::GetPrimVar	(	const RtUString	name,
		RtFloat3 const **	var,
		float const **	dXdu,
		float const **	dYdu,
		float const **	dZdu,
		float const **	dXdv,
		float const **	dYdv,
		float const **	dZdv
	)		const

pure virtual

◆ GetProperty()

virtual bool RixShadingContext::GetProperty	(	RayProperty	,
		void const *
	)		const

inlinevirtual

As long as the RixIntegrator used supports the appropriate ray property query, shading plugin authors may want to query ray properties such as the ray depth or eye throughput, in order to allow for artistic control or optimization.

For instance, as an optimization a RixBxdf may want to skip the evaluation of a particularly expensive lobe, if the current ray depth of the hit point is beyond some arbitrary threshold. This service is provided by GetProperty(). Callers of this routine are responsible for allocating and deallocating the result memory. The integrator is responsible for filling in the result.

Referenced by PxrGeoAOV::Splat().

◆ GetRixInterface()

virtual RixInterface* RixContext::GetRixInterface ( RixInterfaceId id ) const

pure virtualinherited

Get the specified interface from this context.

The generic interface that is returned must be cast to the appropriate type before use.

Referenced by PxrGeoAOV::disableIntegratorAOVs(), RixIES::ReadIESProfile(), RixBXLookupLobeByName(), RixDebugBasis(), RixGetSceneColorSpace(), RixIsHoldout(), and RixIsMatte().

◆ GetSubsurface()

RixVolumeIntegrator* RixShadingContext::GetSubsurface ( ) const

inline

References k_RixSCScatterQuery, k_RixSCVolumeScatterQuery, k_RixSCVolumeTransmissionQuery, and scTraits.

◆ GetTransform()

virtual int RixShadingContext::GetTransform	(	const RtUString	fromSpace,
		const RtUString	toSpace,
		RtMatrix4x4 const **	matrix,
		int *	numMatrices
	)		const

pure virtual

Return an array of matrices numPts in size that represents the transformation from "fromSpace" to "toSpace".

If the transformation is time varying, the numMatrices returned will be the same as numPts in the RixShadingContext. If the transformation is uniform, numMatrices will be set to 1. Zero is returned on success. If fromSpace or toSpace is US_NULL or an empty string, "current" is used instead.

◆ GetVolume()

RixVolumeIntegrator* RixShadingContext::GetVolume ( ) const

inline

References k_RixSCEmissionQuery, k_RixSCScatterQuery, k_RixSCVolumeScatterQuery, k_RixSCVolumeTransmissionQuery, and scTraits.

◆ HasHits()

bool RixShadingContext::HasHits ( ) const

inline

References scTraits.

Referenced by PxrGeoAOV::Splat().

◆ HasMisses()

bool RixShadingContext::HasMisses ( ) const

inline

References scTraits.

◆ HasSubsurface()

virtual bool RixShadingContext::HasSubsurface ( ) const

pure virtual

◆ HasVolume()

virtual bool RixShadingContext::HasVolume ( RixSCVolumeSelector ) const

pure virtual

Support for volume integration:

Begin/EndVolume: can be called by primary integrators to acquire a volume integrator for the selected volume subset (incident or opposite). Depending on the ray path and the requirements of the volume integrator itself, the resulting volume integrator may be bound to a different shading context that was associated with the originating rays. For this reason the incoming ray geometries must be non-const, their shadingCtxIndex may change.

◆ New()

template<class T >

T* RixShadingContext::New	(	size_t	nObjs,
		MemCategory	cat = `k_BxdfMem`
	)		const

inline

New is a utility (fully inlined) non-virtual method to assist with tedious memory allocation tasks.

Note that class-constructor methods may be run on array entries. This cost should be carefully considered for high performance requirements.

References Allocate().

◆ SetBuiltinVar() [1/2]

virtual void RixShadingContext::SetBuiltinVar	(	BuiltinVar	,
		float *	var
	)

pure virtual

SetBuiltinVar() allows the values of any builtin variable to be overridden.

However, for normal shading contexts, SetBuiltinVar() is a no-op. Shaders that wish to change the values of builtin variables must operate on a mutable shading context.

The caller is responsible for providing a pointer to memory allocated with a full RixShadingContext::numPts worth of allocation. This memory will subsequently be owned by the RixShadingContext, and therefore should be allocated using the RixShadingContext's own memory allocation methods (i.e. Allocate()) using the appropriate hint for Bxdf memory duration.

Normally, a shader that alters any single builtin variable is responsible for ensuring that all other builtin variables are also updated appropriately. As a special exception to this, any alteration of the builtin variables u, v, or w by a surface shader will automatically trigger recomputation of P, dPdu, dPdv, and Nn to reflect the updated values of u, v, w, as well as any other builtins that are derived from those values. All other built-in variables will be flushed from the cache and recomputed as necessary. For volume shading, any alteration of P will automatically trigger recomputation of all built-in variables derived from P.

Referenced by RixShiftCtxInU(), and RixShiftCtxInV().

◆ SetBuiltinVar() [2/2]

virtual void RixShadingContext::SetBuiltinVar	(	BuiltinVar	,
		RtFloat3 *	var
	)

pure virtual

◆ SetPrimVar() [1/5]

virtual void RixShadingContext::SetPrimVar	(	const RtUString	name,
		RixSCDetail	d,
		float *	var,
		float *	radius
	)

pure virtual

SetPrimVar: useful for changing state on mutable shading contexts for consumption by upstream pattern-graph nodes.

However, for normal shading contexts, SetPrimVar() is a no-op. Shaders that wish to change the values of builtin variables must operate on a mutable shading context. The caller is responsible for providing a pointer to memory allocated with a full RixShadingContext::numPts worth of allocation. This memory will subsequently be owned by the RixShadingContext, and therefore should be allocated using the RixShadingContext's own memory allocation methods (i.e. Allocate()) using the appropriate hint for Bxdf memory duration.

Unlike GetPrimVar(), SetPrimVar() allows for the creation of primitive variables that are not specified in the original geometry description.

◆ SetPrimVar() [2/5]

virtual void RixShadingContext::SetPrimVar	(	const RtUString	name,
		RixSCDetail	d,
		RtFloat2 *	var,
		float *	radius
	)

pure virtual

◆ SetPrimVar() [3/5]

virtual void RixShadingContext::SetPrimVar	(	const RtUString	name,
		RixSCDetail	d,
		RtFloat3 *	var,
		float *	radius
	)

pure virtual

◆ SetPrimVar() [4/5]

virtual void RixShadingContext::SetPrimVar	(	const RtUString	name,
		RixSCDetail	d,
		RtUString *	var
	)

pure virtual

◆ SetPrimVar() [5/5]

virtual void RixShadingContext::SetPrimVar	(	const RtUString	name,
		RixSCDetail	d,
		RtMatrix4x4 *	var
	)

pure virtual

◆ SetProperty()

virtual bool RixShadingContext::SetProperty	(	RayProperty	,
		void const *
	)		const

inlinevirtual

◆ SetupRngCtxForPattern()

virtual void RixShadingContext::SetupRngCtxForPattern ( ) const

pure virtual

◆ Transform()

virtual int RixShadingContext::Transform	(	TransformInterpretation	interp,
		const RtUString	fromSpace,
		const RtUString	toSpace,
		RtFloat3 *	var,
		float *	radius = `NULL`
	)		const

pure virtual

Transform an array of RtFloat3 (and optional radius) the same size as the numPts in the RixShadingContext.

The type of transformation is specified with TransformInterpretation. If fromSpace or toSpace is US_NULL or an empty string, "current" is used instead. If the call is successful it will return 0.

Friends And Related Function Documentation

◆ LightVertexCache

friend class LightVertexCache

friend

◆ RixVolumeIntegrator

friend class RixVolumeIntegrator

friend

Member Data Documentation

◆ bxdf

RixBxdf* RixShadingContext::bxdf

The bxdf shader is non-NULL for radiance queries and is responsible for computing light scattering.

◆ displacement

RixDisplacement* RixShadingContext::displacement

◆ eyePath

unsigned RixShadingContext::eyePath

◆ integratorCtxIndex

int* RixShadingContext::integratorCtxIndex

integratorCtxIndex maps indices to varying ShadingContext entries to the index associated with IntegratorContext.

The ith element of our integratorCtxIndex tells us the index of the associated primaryRay and other subsidiary channels. The integratorCtxIndex is critical for proper integrator functionality and should be considered "opaque" to the Bxdf.

Referenced by RtRayGeometry::InitOrigination(), RtRayGeometry::InitTransmitOrigination(), and RixIntegrator::IntegrateRays().

◆ light

RixLight const* RixShadingContext::light

◆ lightingServicesData

void* RixShadingContext::lightingServicesData

mutable

lightingServicesData is a blind pointer private RixLightingServices data

◆ lightPath

unsigned RixShadingContext::lightPath

true if shading for an eye path

◆ m_rngCtx

RixRNG* RixShadingContext::m_rngCtx

mutable

◆ m_rngSampleCtx

RixRNG::SampleCtx* RixShadingContext::m_rngSampleCtx

mutableprotected

◆ matteTransmission

RtColorRGB* RixShadingContext::matteTransmission

Similar to transmission but restricted to the transmittance computed solely from matte or holdout volumes.

◆ missContext

unsigned RixShadingContext::missContext

true if shading for a first hit

◆ numPts

int RixShadingContext::numPts

numPts is the number of shading points.

All other non-uniform values can be assumed to have this length.

Referenced by RixIntegrator::IntegrateRays(), RixBump(), RixFresnelDielectric(), RixShiftCtxInU(), RixShiftCtxInV(), and PxrGeoAOV::Splat().

◆ opacity [1/2]

RixOpacity* RixShadingContext::opacity

◆ opacity [2/2]

RtColorRGB* RixShadingContext::opacity

◆ opacityStochasticWeight

float* RixShadingContext::opacityStochasticWeight

◆ opacityThroughput

RtColorRGB* RixShadingContext::opacityThroughput

◆ pointSampleCount

int* RixShadingContext::pointSampleCount

If multiple volume samples are taken for multi scattering, the integrator needs to multiply this value in for thruput.

◆ pointWeight

RtColorRGB* RixShadingContext::pointWeight

If the shading context was created via an importance sampling method, this is the associated weight the integrator needs to multiply in.

◆ postlighting

RixPostLighting* RixShadingContext::postlighting

◆ primaryHit

unsigned RixShadingContext::primaryHit

true if shading for a light path

◆ rayId

int* RixShadingContext::rayId

rayId is similar to integratorCtxIndex.

This array can be used by integrators to track a correspondence between the ShadingContext entries and integrator-specific data structures. The rayId may be critical for proper functionality of a given integrator and should be considered "opaque" to the Bxdf.

◆ reyesGrid

unsigned RixShadingContext::reyesGrid

true if this context represents misses

◆ scTraits

struct { ... } RixShadingContext::scTraits

shadingCtxTraits conveys a variety of (uniform) ShadingContex traits to shader and integrator.

Referenced by GetBxdf(), GetDisplacement(), GetOpacity(), GetPostLighting(), GetSubsurface(), GetVolume(), HasHits(), and HasMisses().

◆ shadingCtxId

struct RixShadingContext::Id RixShadingContext::shadingCtxId

Referenced by RtRayGeometry::InitOrigination(), and RtRayGeometry::InitTransmitOrigination().

◆ shadingMode

RixSCShadingMode RixShadingContext::shadingMode

true if we're operating on a reyes grid this may occur in a variety of caching conditions

shadingMode contains the current mode of operation associated with this shading context.

◆ subsurface

RixVolumeIntegrator* RixShadingContext::subsurface

◆ transmission

RtColorRGB* RixShadingContext::transmission

transmission is a per-point transmission that is associated with the ray that produced the associated hit.

It's used by interiors and volumes to "occlude" the results of the radiance computation of each point.

◆ volume

RixVolumeIntegrator* RixShadingContext::volume

The documentation for this class was generated from the following file:

RixShading.h

Classes

Public Types

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ BuiltinBxdf

◆ BuiltinVar

◆ BuiltinVolume

◆ MemCategory

◆ TransformInterpretation

Constructor & Destructor Documentation

◆ ~RixShadingContext()

Member Function Documentation

◆ Allocate()

◆ BeginIncidentVol()

◆ BeginOppositeVol()

◆ BeginSubsurface()

◆ BeginVolume()

◆ BeginVolumeSampling()

◆ CreateMutableContext()

◆ EndSubsurface()

◆ EndVolume()

◆ EndVolumeSampling()

◆ EvalAndCopyParam()

◆ EvalParam() [1/7]

◆ EvalParam() [2/7]

◆ EvalParam() [3/7]

◆ EvalParam() [4/7]

◆ EvalParam() [5/7]

◆ EvalParam() [6/7]

◆ EvalParam() [7/7]

◆ GetBuiltinBxdf()

◆ GetBuiltinVar() [1/4]

◆ GetBuiltinVar() [2/4]

◆ GetBuiltinVar() [3/4]

◆ GetBuiltinVar() [4/4]

◆ GetBuiltinVolume()

◆ GetBxdf()

◆ GetContextById()

◆ GetDisplacement()

◆ GetDisplayServices()

◆ GetIntegratorContext()

◆ GetLightEmission()

◆ GetNearestHits()

◆ GetOpacity()

◆ GetOverlappingVolumes()

◆ GetParamId()

◆ GetParamInfo() [1/2]

◆ GetParamInfo() [2/2]

◆ GetPostLighting()

◆ GetPrimaryContext()

◆ GetPrimVar() [1/9]

◆ GetPrimVar() [2/9]

◆ GetPrimVar() [3/9]

◆ GetPrimVar() [4/9]

◆ GetPrimVar() [5/9]

◆ GetPrimVar() [6/9]

◆ GetPrimVar() [7/9]

◆ GetPrimVar() [8/9]

◆ GetPrimVar() [9/9]

◆ GetProperty()

◆ GetRixInterface()

◆ GetSubsurface()

◆ GetTransform()

◆ GetVolume()

◆ HasHits()

◆ HasMisses()

◆ HasSubsurface()

◆ HasVolume()

◆ New()

◆ SetBuiltinVar() [1/2]

◆ SetBuiltinVar() [2/2]

◆ SetPrimVar() [1/5]

◆ SetPrimVar() [2/5]

◆ SetPrimVar() [3/5]

◆ SetPrimVar() [4/5]