cugar::cuda::Kd_builder< Integer > Struct Template Reference

Detailed description

template<typename Integer>
struct cugar::cuda::Kd_builder< Integer >

GPU-based middle-split k-d tree builder

This class provides the context to generate k-d trees on the GPU starting from a set of unordered points. 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.

Template Parameters

Integer	an integer type that determines the number of bits used to compute the points' Morton codes. Accepted values are uint32 and uint64.
OutputTree	a template class used to write the output tree, with the following interface:

struct OutputTree
{
   void reserve_nodes(const uint32 n);  // reserve space for n nodes
   void reserve_leaves(const uint32 n); // reserve space for n leaves

   Context get_context();             // get a context to write nodes/leaves

   struct Context
   {
       void write_node(
          const uint32 node,          // node to write
          const uint32 offset,        // child offset
          const uint32 skip_node,     // skip node
          const uint32 begin,         // node range begin
          const uint32 end,           // node range end
          const uint32 split_index,   // split index
          const uint32 split_dim,     // splitting dimension
          const uint32 split_plane);  // splitting plane

       void write_node(
          const uint32 node,          // node to write
          const uint32 offset,        // child offset
          const uint32 skip_node,     // skip node
          const uint32 begin,         // node range begin
          const uint32 end);          // node range end

       void write_leaf(
          const uint32 index,         // leaf to write
          const uint32 begin,         // leaf range begin
          const uint32 end);          // leaf range end
   };
};

The following code snippet shows how to use this builder:

#include <cugar/kd/cuda/kd_builder.h>
#include <cugar/kd/cuda/kd_context.h>

cugar::vector<device_tag,Vector3f> points;
... // code to fill the input vector of points

cugar::vector<device_tag,Kd_node>  kd_nodes;
cugar::vector<device_tag,uint2>    kd_leaves;
cugar::vector<device_tag,uint32>   kd_index;
cugar::vector<device_tag,uint2>    kd_ranges;

cugar::cuda::Kd_builder<uint64> builder( kd_index );
cugar::cuda::Kd_context kd_tree( &kd_nodes, &kd_leaves, &kd_ranges );
builder.build(
    kd_tree,                                    // output tree
    kd_index,                                   // output index
    Bbox3f( Vector3f(0.0f), Vector3f(1.0f) ),   // suppose all bboxes are in [0,1]^3
    points.begin(),                             // begin iterator
    points.end(),                               // end iterator
    4 );                                        // target 4 objects per leaf

#include <kd_builder.h>

Public Methods
template<typename OutputTree , typename Iterator , typename BboxType >
void	build (OutputTree &out_tree, vector< device_tag, uint32 > &out_index, const BboxType bbox, const Iterator points_begin, const Iterator points_end, const uint32 max_leaf_size)

Public Members
vector< device_tag, Integer >	m_codes
caching_device_vector< Integer >	m_temp_codes
caching_device_vector< uint32 >	m_temp_index
uint32	m_node_count
uint32	m_leaf_count
cuda::Radixtree_context	m_kd_context

Member Function Documentation

build()

template<typename Integer >

template<typename OutputTree , typename Iterator , typename BboxType >

void cugar::cuda::Kd_builder< Integer >::build	(	OutputTree &	out_tree,
		vector< device_tag, uint32 > &	out_index,
		const BboxType	bbox,
		const Iterator	points_begin,
		const Iterator	points_end,
		const uint32	max_leaf_size
	)

build a bvh given a set of points that will be reordered in-place

Parameters

out_tree	output tree
out_index	output index
bbox	global bbox
points_begin	beginning of the point sequence to sort
points_end	end of the point sequence to sort
max_leaf_size	maximum leaf size

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

• C:/p4research/research/jpantaleoni/Fermat-Public/contrib/cugar/kd/cuda/kd_builder.h
• C:/p4research/research/jpantaleoni/Fermat-Public/contrib/cugar/kd/cuda/kd_builder_inline.h