nih::cuda::Sah_builder Struct Reference

Detailed description

GPU-based SAH BVH builder.

GPU-based SAH BVH builder.

This builders provides the context to generate a bounding volume hierarchy using the Surface Area Heuristic out of a generic set of unsorted bounding boxes. The output is a set of nodes with the corresponding leaves and a set of primitive indices into the input set of points. The output leaves will specify contiguous ranges into this index.

The following code snippet shows how to use this builder:

#include <nih/bvh/cuda/sah_builder.h>

thrust::device_vector<Bbox4f>   bboxes;
... // code to fill the input vector of bboxes

thrust::device_vector<Bvh_node> bvh_nodes;
thrust::device_vector<uint2>    bvh_leaves;
thrust::device_vector<uint32>   bvh_index;

nih::cuda::Sah_builder builder( bvh_nodes, bvh_leaves, bvh_index );
builder.build(
    Bbox3f( Vector3f(0.0f), Vector3f(1.0f) ),   // suppose all bboxes are in [0,1]^3
    bboxes.begin(),                             // begin iterator
    bboxes.end(),                               // end iterator
    4 );                                        // target 4 objects per leaf

#include <sah_builder.h>

Classes
struct	Bbox
struct	Bin
struct	Bins
struct	Objects
struct	Queue
struct	Split

Public Methods
	Sah_builder (thrust::device_vector< Bvh_node > &nodes, thrust::device_vector< uint2 > &leaves, thrust::device_vector< uint32 > &index)
	constructor
template<typename Iterator >
void	build (const uint32 BINS, const Bbox3f bbox, const Iterator bbox_begin, const Iterator bbox_end, const uint32 max_leaf_size, const float max_cost=1.8f)
	build a bvh given a set of bboxes
	Sah_builder (thrust::device_vector< Bvh_node > &nodes, thrust::device_vector< uint2 > &leaves, thrust::device_vector< uint32 > &index)
template<typename Iterator >
void	build (const Bbox3f bbox, const Iterator bbox_begin, const Iterator bbox_end, const uint32 max_leaf_size, const float max_cost=1.8f)

Public Members
thrust::device_vector< Bvh_node > *	m_nodes
thrust::device_vector< uint2 > *	m_leaves
thrust::device_vector< uint32 > *	m_index
uint32	m_levels [128]
uint32	m_level_count
Bbox3f	m_bbox
uint32	m_node_count
uint32	m_leaf_count
float	m_init_bins_time
float	m_update_bins_time
float	m_sah_split_time
float	m_distribute_objects_time
thrust::device_vector< float3 >	m_bin_bmin
thrust::device_vector< float3 >	m_bin_bmax
thrust::device_vector< int32 >	m_bin_size
thrust::device_vector< Bin >	m_queue_bins
thrust::device_vector< Split >	m_queue_splits
thrust::device_vector< uint32 >	m_queue_offsets
thrust::device_vector< int4 >	m_bin_ids
thrust::device_vector< int32 >	m_split_ids
thrust::device_vector< int32 >	m_node_ids
thrust::device_vector< uint32 >	m_new_pos
thrust::device_vector< uint32 >	m_counters
float	m_sorting_time
float	m_compression_time
uint32	m_temp_storage

Constructor & Destructor Documentation

Sah_builder()

nih::cuda::Sah_builder::Sah_builder ( thrust::device_vector< Bvh_node > &  nodes, thrust::device_vector< uint2 > &  leaves, thrust::device_vector< uint32 > &  index  )

inline

constructor

Parameters

nodes	output nodes array
leaves	output leaf array
index	output index array

Member Function Documentation

build()

template<typename Iterator >

void nih::cuda::Sah_builder::build	(	const Bbox3f	bbox,
		const Iterator	bbox_begin,
		const Iterator	bbox_end,
		const uint32	max_leaf_size,
		const float	max_cost = 1.8f
	)

build a bvh given a set of bboxes. The bbox iterators must be thrust-compatible (i.e. implementing dereference()).

Parameters

bbox	global bbox
bbox_begin	beginning of the bbox sequence
bbox_end	end of the bbox sequence
max_leaf_size	maximum leaf size
max_cost	maximum cost relative to the parent

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

• C:/p4research/research/jpantaleoni/Fermat-Public/contrib/cugar/bvh/cuda/backup/sah_builder.h
• C:/p4research/research/jpantaleoni/Fermat-Public/contrib/cugar/bvh/cuda/backup/sah_builder_inline.h