Inherits G3D::ReferenceCountedObject.

Classes
class	BufferSet
	Per-path data passed between major routines. More...

class	Options

Public Member Functions
void	prepare (const Options &options) const
	Call on the main thread if you wish to force GPU->CPU conversion and tree building to happen right now. More...

void	setScene (const shared_ptr< Scene > &scene)
	Replaces the previous scene. More...

void	traceBuffer (Array< Ray > &rayBuffer, Radiance3 output, const Options &options, bool lightEmissiveOnFirstHit, const float weight=nullptr, float distance=nullptr, Vector3 primaryWSNormalBuffer=nullptr, Color3 *primaryAlbedoBuffer=nullptr) const
	More...

void	traceImage (const shared_ptr< Image > &radianceImage, const shared_ptr< Camera > &camera, const Options &options, const std::function< void(const String &, float)> &statusCallback=nullptr) const
	Assumes that the scene has been previously set. More...

const shared_ptr< TriTree > &	triTree () const

Static Public Member Functions
static shared_ptr< PathTracer >	create (shared_ptr< TriTree > t=nullptr)

Protected Types
typedef Point2	PixelCoord

Protected Member Functions
	PathTracer (const shared_ptr< TriTree > &t=nullptr)

void	addEmissive (const Array< Ray > &rayFromEye, const Array< shared_ptr< Surfel >> &surfelBuffer, const Array< bool > &impulseRay, const Array< Color3 > &modulationBuffer, Radiance3 *outputBuffer, const Array< int > outputCoordBuffer, const shared_ptr< Image > &radianceImage, const Array< PixelCoord > &pixelCoordBuffer) const
	In a properly modeled scene with area lights and no duplicating point lights, we should only count this term on the first bounce. More...

void	computeDirectIllumination (const Array< shared_ptr< Surfel >> &surfelBuffer, const Array< shared_ptr< Light >> &lightArray, const Array< Ray > &rayBuffer, int currentPathDepth, int currentRayIndex, const Options &options, const Array< PixelCoord > &pixelCoordBuffer, const int radianceImageWidth, Array< Radiance3 > &directBuffer, Array< Ray > &shadowRayBuffer) const
	Choose what light surface to sample, storing the corresponding shadow ray and biradiance value. More...

void	generateEyeRays (int width, int height, const shared_ptr< Camera > &camera, Array< Ray > &rayBuffer, bool randomSubpixelPosition, Array< PixelCoord > &pixelCoordBuffer, const shared_ptr< Image > &weightSumImage, int rayIndex, int raysPerPixel) const
	Produces a buffer of eye rays, stored in raster order in the preallocated rayBuffer. More...

const shared_ptr< Light > &	importanceSampleLight (const Array< shared_ptr< Light >> &lightArray, const Vector3 &w_o, const shared_ptr< Surfel > &surfel, int sequenceIndex, int rayIndex, int raysPerPixel, Biradiance3 &biradiance, Color3 &cosBSDFDivPDF, Point3 &lightPosition) const
	sequenceIndex = (pixelIndex * maxPathDepth) + currentPathDepth) More...

void	prepare (const Options &options, Array< shared_ptr< Light >> &directLightArray, Array< shared_ptr< Light >> &indirectLightArray) const

Point3	sampleOneLight (const shared_ptr< Light > &light, const Point3 &X, const Vector3 &n, int pixelIndex, int lightIndex, int sampleIndex, int numSamples, float &areaTimesPDFValue) const
	Sample a single light and choose a point on it, potentially in a low-discrepancy or importance sampling way. More...

virtual void	scatterRays (const Array< shared_ptr< Surfel >> &surfelBuffer, const Array< shared_ptr< Light >> &indirectLightArray, int currentPathDepth, int rayIndex, int raysPerPixel, Array< Ray > &rayBuffer, Array< Color3 > &modulationBuffer, Array< bool > &impulseScatterBuffer) const
	Compute the next bounce direction by mutating rayBuffer, and then multiply the modulationBuffer by the inverse probability density that the direction was taken. More...

virtual void	shade (const Array< shared_ptr< Surfel >> &surfelBuffer, const Array< Ray > &rayFromEye, const Array< Ray > &rayFromLight, const Array< bool > &lightShadowedBuffer, const Array< Radiance3 > &directBuffer, const Array< Color3 > &modulationBuffer, Radiance3 *outputBuffer, const Array< int > outputCoordBuffer, const shared_ptr< Image > &radianceImage, const Array< PixelCoord > &pixelCoordBuffer) const
	Apply the BSDF for each surfel to the biradiance in the corresponding light (unless shadowed), modulate as specified, and add to the image. More...

Radiance3	skyRadiance (const Vector3 &direction) const

virtual void	traceBufferInternal (BufferSet &buffers, Radiance3 output, const shared_ptr< Image > &radianceImage, float distance, const Array< shared_ptr< Light >> &directLightArray, const Array< shared_ptr< Light >> &indirectLightArray, int currentRayIndex) const
	Called from traceBuffer after the options are set and scene is processed. More...

Static Protected Member Functions
template<class T , class ... ArgTypes>
static shared_ptr< T >	createShared (ArgTypes &&... args)
	Like std::make_shared, but works for protected constructors. More...

Protected Attributes
shared_ptr< CubeMap >	m_environmentMap

Options	m_options
	For the active trace. More...

shared_ptr< Scene >	m_scene

shared_ptr< CubeMap >	m_skybox

shared_ptr< TriTree >	m_triTree

Static Protected Attributes
static const Ray	s_degenerateRay

Member Typedef Documentation

◆ PixelCoord

typedef Point2 G3D::PathTracer::PixelCoord

protected

Constructor & Destructor Documentation

◆ PathTracer()

G3D::PathTracer::PathTracer ( const shared_ptr< TriTree > & t = nullptr )

protected

Member Function Documentation

◆ addEmissive()

void G3D::PathTracer::addEmissive	(	const Array< Ray > &	rayFromEye,
		const Array< shared_ptr< Surfel >> &	surfelBuffer,
		const Array< bool > &	impulseRay,
		const Array< Color3 > &	modulationBuffer,
		Radiance3 *	outputBuffer,
		const Array< int >	outputCoordBuffer,
		const shared_ptr< Image > &	radianceImage,
		const Array< PixelCoord > &	pixelCoordBuffer
	)		const

protected

In a properly modeled scene with area lights and no duplicating point lights, we should only count this term on the first bounce.

However, we're only going to sample point lights explicitly, so we need emissive on every bounce. Scenes like G3D cornell box where there are both point and emissives in the same location will get brighter than expected as a result.

If outputBuffer is not null, writes to it using outputCoordBuffer indices, otherwise writes to radianceImage using pixelCoordBuffer indices.

◆ computeDirectIllumination()

void G3D::PathTracer::computeDirectIllumination	(	const Array< shared_ptr< Surfel >> &	surfelBuffer,
		const Array< shared_ptr< Light >> &	lightArray,
		const Array< Ray > &	rayBuffer,
		int	currentPathDepth,
		int	currentRayIndex,
		const Options &	options,
		const Array< PixelCoord > &	pixelCoordBuffer,
		const int	radianceImageWidth,
		Array< Radiance3 > &	directBuffer,
		Array< Ray > &	shadowRayBuffer
	)		const

protected

Choose what light surface to sample, storing the corresponding shadow ray and biradiance value.

◆ create()

static shared_ptr<PathTracer> G3D::PathTracer::create ( shared_ptr< TriTree > t = nullptr )

static

◆ createShared()

template<class T , class ... ArgTypes>

static shared_ptr<T> G3D::ReferenceCountedObject::createShared ( ArgTypes &&... args )

inlinestaticprotectedinherited

Like std::make_shared, but works for protected constructors.

Call as createShared<myclass>.

◆ generateEyeRays()

void G3D::PathTracer::generateEyeRays	(	int	width,
		int	height,
		const shared_ptr< Camera > &	camera,
		Array< Ray > &	rayBuffer,
		bool	randomSubpixelPosition,
		Array< PixelCoord > &	pixelCoordBuffer,
		const shared_ptr< Image > &	weightSumImage,
		int	rayIndex,
		int	raysPerPixel
	)		const

protected

Produces a buffer of eye rays, stored in raster order in the preallocated rayBuffer.

Parameters

castThroughCenter	When true (for the first ray at each pixel), cast the ray through the pixel center to make images look less noisy.
raysPerPixel
rayIndex	between 0 and raysPerPixel - 1, used for lens low-discrepancy sampling

◆ importanceSampleLight()

const shared_ptr<Light>& G3D::PathTracer::importanceSampleLight	(	const Array< shared_ptr< Light >> &	lightArray,
		const Vector3 &	w_o,
		const shared_ptr< Surfel > &	surfel,
		int	sequenceIndex,
		int	rayIndex,
		int	raysPerPixel,
		Biradiance3 &	biradiance,
		Color3 &	cosBSDFDivPDF,
		Point3 &	lightPosition
	)		const

protected

sequenceIndex = (pixelIndex * maxPathDepth) + currentPathDepth)

Parameters

probability Relative probablity mass with which this particular sample was taken relative to other samples that were considered.

◆ prepare() [1/2]

void G3D::PathTracer::prepare	(	const Options &	options,
		Array< shared_ptr< Light >> &	directLightArray,
		Array< shared_ptr< Light >> &	indirectLightArray
	)		const

protected

Referenced by prepare().

◆ prepare() [2/2]

void G3D::PathTracer::prepare ( const Options & options ) const

inline

Call on the main thread if you wish to force GPU->CPU conversion and tree building to happen right now.

◆ sampleOneLight()

Point3 G3D::PathTracer::sampleOneLight	(	const shared_ptr< Light > &	light,
		const Point3 &	X,
		const Vector3 &	n,
		int	pixelIndex,
		int	lightIndex,
		int	sampleIndex,
		int	numSamples,
		float &	areaTimesPDFValue
	)		const

protected

Sample a single light and choose a point on it, potentially in a low-discrepancy or importance sampling way.

areaTimesPDFValue Return value that is the area of the light times the differential probability with which each point was selected.For uniform selection, this value is just 1.0f.

X the point from which the light will be viewed. Set to Point3::NaN to ignore. n the surface normal at X. Set to Point3::NaN to ignore.

See also: Light::lowDiscrepancyPosition

◆ scatterRays()

virtual void G3D::PathTracer::scatterRays	(	const Array< shared_ptr< Surfel >> &	surfelBuffer,
		const Array< shared_ptr< Light >> &	indirectLightArray,
		int	currentPathDepth,
		int	rayIndex,
		int	raysPerPixel,
		Array< Ray > &	rayBuffer,
		Array< Color3 > &	modulationBuffer,
		Array< bool > &	impulseScatterBuffer
	)		const

protectedvirtual

Compute the next bounce direction by mutating rayBuffer, and then multiply the modulationBuffer by the inverse probability density that the direction was taken.

Those probabilities are computed across three color channels, so modulationBuffer can become "colored" by this.

◆ setScene()

void G3D::PathTracer::setScene ( const shared_ptr< Scene > & scene )

Replaces the previous scene.

◆ shade()

virtual void G3D::PathTracer::shade	(	const Array< shared_ptr< Surfel >> &	surfelBuffer,
		const Array< Ray > &	rayFromEye,
		const Array< Ray > &	rayFromLight,
		const Array< bool > &	lightShadowedBuffer,
		const Array< Radiance3 > &	directBuffer,
		const Array< Color3 > &	modulationBuffer,
		Radiance3 *	outputBuffer,
		const Array< int >	outputCoordBuffer,
		const shared_ptr< Image > &	radianceImage,
		const Array< PixelCoord > &	pixelCoordBuffer
	)		const

protectedvirtual

Apply the BSDF for each surfel to the biradiance in the corresponding light (unless shadowed), modulate as specified, and add to the image.

Emissive light is only added for primary surfaces since it is already accounted for by explicit light sampling.

If outputBuffer is not null, writes to it using outputCoordBuffer indices, otherwise writes to radianceImage using pixelCoordBuffer indices.

◆ skyRadiance()

Radiance3 G3D::PathTracer::skyRadiance ( const Vector3 & direction ) const

protected

◆ traceBuffer()

void G3D::PathTracer::traceBuffer	(	Array< Ray > &	rayBuffer,
		Radiance3 *	output,
		const Options &	options,
		bool	lightEmissiveOnFirstHit,
		const float *	weight = `nullptr`,
		float *	distance = `nullptr`,
		Vector3 *	primaryWSNormalBuffer = `nullptr`,
		Color3 *	primaryAlbedoBuffer = `nullptr`
	)		const

Parameters

output	Must be allocated to at least the size of rayBuffer. This may be uncached, memory mapped memory.
weight	if not null, each output is scaled by the corresponding weight.

The rayBuffer will be modified. Make a copy if you wish to preserve the initial values.

Parameters

distance	If not null, this is filled with the hit distance to the primary surface for each ray. Misses are set to infinity.
lightEmissiveOnFirstHit	Should the first hit be treated as a primary/impulse hit and include the emissive term from a light source surface?
primaryWSNormalBuffer	If not null, the normal at the primary hit point for each ray. NaN if no hit.
primaryAlbedoBuffer	If not null, a color at the primary hit point.

◆ traceBufferInternal()

virtual void G3D::PathTracer::traceBufferInternal	(	BufferSet &	buffers,
		Radiance3 *	output,
		const shared_ptr< Image > &	radianceImage,
		float *	distance,
		const Array< shared_ptr< Light >> &	directLightArray,
		const Array< shared_ptr< Light >> &	indirectLightArray,
		int	currentRayIndex
	)		const

protectedvirtual

Called from traceBuffer after the options are set and scene is processed.

Parameters

currentRayIndex If you are tracing multiple rays per pixel, this is the loop index of these rays.

If output is not null, the output is written there. Otherwise the output is bilinearly blended into the radianceImage and the pixelCoordBuffer is used.

If weight is not null, it is an array of per-output weights.

If distance is not null, the distance to each primary hit is written to it (not the "Z" value).

◆ traceImage()

void G3D::PathTracer::traceImage	(	const shared_ptr< Image > &	radianceImage,
		const shared_ptr< Camera > &	camera,
		const Options &	options,
		const std::function< void(const String &, float)> &	statusCallback = `nullptr`
	)		const

Assumes that the scene has been previously set.

Only rebuilds the tree if the scene has changed.

Parameters

statusCallback Function called periodically to update the GUI with the rendering progress. Arguments are percentage (between 0 and 1) and an arbitrary message string.

◆ triTree()

const shared_ptr<TriTree>& G3D::PathTracer::triTree ( ) const

inline

Member Data Documentation

◆ m_environmentMap

shared_ptr<CubeMap> G3D::PathTracer::m_environmentMap

mutableprotected

See also: Options:: useEnvironmentMapForLastScatteringEvent

◆ m_options

Options G3D::PathTracer::m_options

mutableprotected

For the active trace.

◆ m_scene

shared_ptr<Scene> G3D::PathTracer::m_scene

protected

◆ m_skybox

shared_ptr<CubeMap> G3D::PathTracer::m_skybox

mutableprotected

◆ m_triTree

shared_ptr<TriTree> G3D::PathTracer::m_triTree

mutableprotected

Referenced by triTree().

◆ s_degenerateRay

const Ray G3D::PathTracer::s_degenerateRay

staticprotected

Classes

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Member Typedef Documentation

◆ PixelCoord

Constructor & Destructor Documentation

◆ PathTracer()

Member Function Documentation

◆ addEmissive()

◆ computeDirectIllumination()

◆ create()

◆ createShared()

◆ generateEyeRays()

◆ importanceSampleLight()

◆ prepare() [1/2]

◆ prepare() [2/2]

◆ sampleOneLight()

◆ scatterRays()

◆ setScene()

◆ shade()

◆ skyRadiance()

◆ traceBuffer()

◆ traceBufferInternal()

◆ traceImage()

◆ triTree()

Member Data Documentation

◆ m_environmentMap

◆ m_options

◆ m_scene

◆ m_skybox

◆ m_triTree

◆ s_degenerateRay