BPTLib

Detailed Description

This module provides a flexible bidirectional path tracing library, thought to be as performant as possible and yet vastly configurable at compile-time. For more information, see the BPTLib page.

Modules
	BPTLibCore

Classes
struct	BPTContextBase< TBPTOptions >
struct	BPTConfigBase
struct	SampleSinkBase
struct	BPTOptionsBase
struct	BPTQueuesView
struct	BPTQueuesStorage
struct	TiledLightSubpathPrimaryCoords
struct	PerPixelEyeSubpathPrimaryCoords
struct	PerturbedPrimaryCoords

Macros
#define	SECONDARY_EYE_VERTICES_BLOCKSIZE   128
#define	SECONDARY_EYE_VERTICES_CTA_BLOCKS   6
#define	SECONDARY_LIGHT_VERTICES_BLOCKSIZE   128
#define	SECONDARY_LIGHT_VERTICES_CTA_BLOCKS   6
#define	BPT_FULL_BSDF_EVALUATION   1

Functions
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
void	bpt::sample_light_subpaths (const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext &context, const TBPTConfig &config, RenderingContext &renderer, RenderingContextView &renderer_view)
template<typename TSampleSink , typename TBPTContext >
void	bpt::solve_shadows (TSampleSink sample_sink, TBPTContext &context, RenderingContext &renderer, RenderingContextView &renderer_view)
template<typename TPrimaryCoordinates , typename TSampleSink , typename TBPTContext , typename TBPTConfig >
void	bpt::sample_eye_subpaths (const uint32 n_eye_paths, const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TSampleSink sample_sink, TBPTContext &context, const TBPTConfig &config, RenderingContext &renderer, RenderingContextView &renderer_view, const bool lazy_shadows=false)
template<typename TEyePrimaryCoordinates , typename TLightPrimaryCoordinates , typename TSampleSink , typename TBPTContext , typename TBPTConfig >
void	bpt::sample_paths (const uint32 n_eye_paths, const uint32 n_light_paths, TEyePrimaryCoordinates eye_primary_coords, TLightPrimaryCoordinates light_primary_coords, TSampleSink sample_sink, TBPTContext &context, const TBPTConfig &config, RenderingContext &renderer, RenderingContextView &renderer_view, const bool lazy_shadows=false)
template<typename TSampleSink , typename TBPTContext , typename TBPTConfig >
void	bpt::light_tracing (const uint32 n_light_paths, TSampleSink sample_sink, TBPTContext &context, const TBPTConfig &config, RenderingContext &renderer, RenderingContextView &renderer_view)
template<typename TBPTContext , typename TBPTConfig >
__global__ void	bpt::light_tracing_kernel (const uint32 n_light_paths, TBPTContext context, RenderingContextView renderer, TBPTConfig config)
template<typename TBPTContext , typename TBPTConfig >
void	bpt::light_tracing (const uint32 n_light_paths, TBPTContext &context, RenderingContextView &renderer, TBPTConfig &config)
template<typename TSampleSink , typename TBPTContext >
__global__ void	bpt::solve_occlusions_kernel (const uint32 in_queue_size, TSampleSink sample_sink, TBPTContext context, RenderingContextView renderer)
template<typename TSampleSink , typename TBPTContext >
void	bpt::solve_occlusions (const uint32 in_queue_size, TSampleSink sample_sink, TBPTContext context, RenderingContextView renderer)
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
__global__ void	bpt::generate_primary_light_vertices_kernel (const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
void	bpt::generate_primary_light_vertices (const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
__global__	bpt::__launch_bounds__ (SECONDARY_LIGHT_VERTICES_BLOCKSIZE, SECONDARY_LIGHT_VERTICES_CTA_BLOCKS) void process_secondary_light_vertices_kernel(const uint32 in_queue_size
	bpt::if (thread_id< in_queue_size) process_secondary_light_vertex(thread_id
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
void	bpt::process_secondary_light_vertices (const uint32 in_queue_size, const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)
template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
__global__ void	bpt::generate_primary_eye_vertices_kernel (const uint32 n_eye_paths, const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)
template<typename TPrimaryCoordinates , typename TBPTConfig , typename TBPTContext >
void	bpt::generate_primary_eye_vertices (const uint32 n_eye_paths, const uint32 n_light_paths, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)
template<typename TSampleSink , typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
__global__	bpt::__launch_bounds__ (SECONDARY_EYE_VERTICES_BLOCKSIZE, SECONDARY_EYE_VERTICES_CTA_BLOCKS) void process_secondary_eye_vertices_kernel(const uint32 in_queue_size
template<typename TSampleSink , typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >
void	bpt::process_secondary_eye_vertices (const uint32 in_queue_size, const uint32 n_eye_paths, const uint32 n_light_paths, TSampleSink sink, TPrimaryCoordinates primary_coords, TBPTContext context, RenderingContextView renderer, const TBPTConfig config)

Variables
__global__ const uint32	bpt::n_light_paths
__global__ const uint32 TPrimaryCoordinates	bpt::primary_coords
__global__ const uint32 TPrimaryCoordinates TBPTContext	bpt::context
__global__ const uint32 TPrimaryCoordinates TBPTContext RenderingContextView	bpt::renderer
__global__ const uint32 TPrimaryCoordinates TBPTContext RenderingContextView const TBPTConfig	bpt::config
__global__ const uint32	bpt::n_eye_paths
__global__ const uint32 const uint32 TSampleSink	bpt::sink

Function Documentation

light_tracing()

template<typename TSampleSink , typename TBPTContext , typename TBPTConfig >

void bpt::light_tracing	(	const uint32	n_light_paths,
		TSampleSink	sample_sink,
		TBPTContext &	context,
		const TBPTConfig &	config,
		RenderingContext &	renderer,
		RenderingContextView &	renderer_view
	)

A host function dispatching a series of kernels to process pure light tracing paths. Specifically, this function executes the following two functions:

• light_tracing()
• solve_shadows()

This function needs to be called after a previous call to generate_light_subpaths(), as it assumes a set of light subpaths have already been sampled and it is possible to connect them to the camera.

Template Parameters

TSampleSink	a sample sink, specifying what to do with each generated path sample, see SampleSinkAnchor
TBPTContext	a bidirectional path tracing context class, see BPTContextBase
TBPTConfig	a policy class controlling the behaviour of the path sampling process, see BPTConfigBase

sample_eye_subpaths()

template<typename TPrimaryCoordinates , typename TSampleSink , typename TBPTContext , typename TBPTConfig >

void bpt::sample_eye_subpaths	(	const uint32	n_eye_paths,
		const uint32	n_light_paths,
		TPrimaryCoordinates	primary_coords,
		TSampleSink	sample_sink,
		TBPTContext &	context,
		const TBPTConfig &	config,
		RenderingContext &	renderer,
		RenderingContextView &	renderer_view,
		const bool	lazy_shadows = false
	)

A host function dispatching a series of kernels to sample a given number of eye subpaths. The generated subpaths are controlled by a user-defined set of primary space coordinates. Specifically, this function executes a pipeline comprised of the following kernels:

• generate_primary_eye_vertices()
• RTContext::trace()
• process_secondary_eye_vertices()
• solve_shadows()

This function needs to be called after a previous call to generate_light_subpaths(), as it assumes a set of light subpaths have already been sampled and it is possible to sample and perform connections between the pre-existing light vertices and each new eye vertex. A templated sample sink class specifies what to do with the full light path samples generated in this phase (i.e. the paths hitting an emissive surface), while the generated "connection" samples are stored in a queue controlled by the templated policy config class. These connections are processed by the solve_shadows() function.

Template Parameters

TPrimaryCoordinates	a set of primary space coordinates, TPrimaryCoordinatesAnchor
TSampleSink	a sample sink, specifying what to do with each generated path sample, see SampleSinkAnchor
TBPTContext	a bidirectional path tracing context class, see BPTContextBase
TBPTConfig	a policy class controlling the behaviour of the path sampling process, see BPTConfigBase

sample_light_subpaths()

template<typename TPrimaryCoordinates , typename TBPTContext , typename TBPTConfig >

void bpt::sample_light_subpaths	(	const uint32	n_light_paths,
		TPrimaryCoordinates	primary_coords,
		TBPTContext &	context,
		const TBPTConfig &	config,
		RenderingContext &	renderer,
		RenderingContextView &	renderer_view
	)

A host function dispatching a series of kernels to sample a given number of light subpaths. The generated subpaths are controlled by a user-defined set of primary space coordinates. Specifically, this function executes a pipeline comprised of the following kernels:

• generate_primary_light_vertices()
• RTContext::trace()
• process_secondary_light_vertices()

A templated policy config class specifies what to do with the generated light vertices.

Template Parameters

TPrimaryCoordinates	a set of primary space coordinates, TPrimaryCoordinatesAnchor
TBPTContext	a bidirectional path tracing context class, see BPTContextBase
TBPTConfig	a policy class controlling the behaviour of the path sampling process, see BPTConfigBase

sample_paths()

template<typename TEyePrimaryCoordinates , typename TLightPrimaryCoordinates , typename TSampleSink , typename TBPTContext , typename TBPTConfig >

void bpt::sample_paths	(	const uint32	n_eye_paths,
		const uint32	n_light_paths,
		TEyePrimaryCoordinates	eye_primary_coords,
		TLightPrimaryCoordinates	light_primary_coords,
		TSampleSink	sample_sink,
		TBPTContext &	context,
		const TBPTConfig &	config,
		RenderingContext &	renderer,
		RenderingContextView &	renderer_view,
		const bool	lazy_shadows = false
	)

A host function dispatching a series of kernels to sample a given number of full paths. The generated paths are controlled by two user-defined sets of primary space coordinates, one for eye and light subpaths sampling. Specifically, this function executes the following two functions:

• sample_light_subpaths()
• sample_eye_subpaths()

Template Parameters

TEyePrimaryCoordinates	a set of primary space coordinates, TPrimaryCoordinatesAnchor
TLightPrimaryCoordinates	a set of primary space coordinates, TPrimaryCoordinatesAnchor
TSampleSink	a sample sink, specifying what to do with each generated path sample, see SampleSinkAnchor
TBPTContext	a bidirectional path tracing context class, see BPTContextBase
TBPTConfig	a policy class controlling the behaviour of the path sampling process, see BPTConfigBase

solve_shadows()

template<typename TSampleSink , typename TBPTContext >

void bpt::solve_shadows	(	TSampleSink	sample_sink,
		TBPTContext &	context,
		RenderingContext &	renderer,
		RenderingContextView &	renderer_view
	)

A host function dispatching a series of kernels to resolve shadows / occlusion of the queued bidirectional connection samples generated by the sample_eye_subpaths function.

Template Parameters

TSampleSink	a sample sink, specifying what to do with each generated path sample, see SampleSinkAnchor
TBPTContext	a bidirectional path tracing context class, see BPTContextBase

Variable Documentation

config

__global__ const uint32 const uint32 TSampleSink TPrimaryCoordinates TBPTContext RenderingContextView const TBPTConfig bpt::config

Initial value:

{
    const uint32 thread_id = threadIdx.x + blockIdx.x * blockDim.x