mitsuba::DirectSamplingRecord Struct Reference

Record for solid-angle based area sampling techniques. More...

#include <mitsuba/render/common.h>

Inheritance diagram for mitsuba::DirectSamplingRecord:

Public Member Functions
	DirectSamplingRecord ()
	Create an invalid direct sampling record. More...
	DirectSamplingRecord (const Point &ref, Float time)
	Create an new direct sampling record for a reference point ref located somewhere in space (i.e. not on a surface) More...
	DirectSamplingRecord (const Intersection &refIts)
	Create an new direct sampling record for a reference point ref located on a surface. More...
	DirectSamplingRecord (const MediumSamplingRecord &mRec)
	Create an new direct sampling record for a reference point ref located in a medium. More...
void	setQuery (const Ray &ray, const Intersection &its, EMeasure measure=ESolidAngle)
	Create a direct sampling record, which can be used to query the density of a surface position (where there reference point lies on a surface) More...
std::string	toString () const
	Return a human-readable description of the record. More...
Public Member Functions inherited from mitsuba::PositionSamplingRecord
	PositionSamplingRecord ()
	Create an invalid position sampling record. More...
	PositionSamplingRecord (Float time)
	Create a new position sampling record that can be passed e.g. to Shape::samplePosition. More...
	PositionSamplingRecord (const Intersection &its, EMeasure measure=EArea)
	Create a position sampling record from a surface intersection. More...
std::string	toString () const
	Return a human-readable description of the record. More...

Public Attributes
Point	ref
	Reference point for direct sampling. More...
Normal	refN
	Optional: normal vector associated with the reference point. More...
Vector	d
	Unit direction from the reference point to the target direction. More...
Float	dist
	Distance from the reference point to the target direction. More...
Public Attributes inherited from mitsuba::PositionSamplingRecord
Point	p
	Sampled position. More...
Float	time
	Associated time value. More...
Normal	n
	Sampled surface normal (if applicable) More...
Float	pdf
	Probability density at the sample. More...
EMeasure	measure
	Denotes the measure associated with the sample. More...
Point2	uv
	Optional: 2D sample position associated with the record. More...
const ConfigurableObject *	object
	Optional: Pointer to an associated object. More...

Detailed Description

Record for solid-angle based area sampling techniques.

This sampling record is used to implement techniques that randomly pick a position on the surface of an object with the goal of importance sampling a quantity that is defined over the sphere seen from a given reference point.

This general approach for sampling positions is named "direct" sampling throughout Mitsuba motivated by direct illumination rendering techniques, which represent the most important application.

This record inherits all fields from PositionSamplingRecord and extends it with two useful quantities that are cached so that they don't need to be recomputed many times: the unit direction and length from the reference position to the sampled point.

Constructor & Destructor Documentation

mitsuba::DirectSamplingRecord::DirectSamplingRecord ( )

inline

Create an invalid direct sampling record.

mitsuba::DirectSamplingRecord::DirectSamplingRecord ( const Point &  ref, Float  time  )

inline

Create an new direct sampling record for a reference point ref located somewhere in space (i.e. not on a surface)

Parameters

ref	The reference point
time	An associated time value

DirectSamplingRecord::DirectSamplingRecord ( const Intersection &  refIts )

inline

Create an new direct sampling record for a reference point ref located on a surface.

Parameters

its	The reference point specified using an intersection record

mitsuba::DirectSamplingRecord::DirectSamplingRecord ( const MediumSamplingRecord &  mRec )

inline

Create an new direct sampling record for a reference point ref located in a medium.

Parameters

mRec	The reference point specified using an medium sampling record

Member Function Documentation

void DirectSamplingRecord::setQuery ( const Ray &  ray, const Intersection &  its, EMeasure  measure = ESolidAngle  )

inline

Create a direct sampling record, which can be used to query the density of a surface position (where there reference point lies on a surface)

Parameters

ray	Reference to the ray that generated the intersection its. The ray origin must be located at refIts.p
its	A surface intersection record (usually on an emitter)

std::string mitsuba::DirectSamplingRecord::toString

(

)

const

Return a human-readable description of the record.

Member Data Documentation

Vector mitsuba::DirectSamplingRecord::d

Unit direction from the reference point to the target direction.

Float mitsuba::DirectSamplingRecord::dist

Distance from the reference point to the target direction.

Point mitsuba::DirectSamplingRecord::ref

Reference point for direct sampling.

Normal mitsuba::DirectSamplingRecord::refN

Optional: normal vector associated with the reference point.

When nonzero, the direct sampling method can use the normal vector to sample according to the projected solid angle at ref.

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The documentation for this struct was generated from the following files:

• include/mitsuba/render/common.h
• include/mitsuba/render/records.inl