Bvh

Bounding Volume Hierarchy container. (BVH tree) More...

#include <bvh.hpp>

Classes
struct	Node
	BVH node container. More...

Public Member Functions
	Bvh (const uint8 *vertices, const uint8 *indices, const Aabb &rootAabb, uint32 indexCount, uint32 vertexSize, uint32 indexSize, const f32x4 *centroids=nullptr)
	Creates a new BVH from the triangle array.
	Bvh (const Aabb *aabbs, const Aabb &rootAabb, uint32 aabbCount, const f32x4 *centroids=nullptr)
	Creates a new BVH from the AABB array.
	Bvh ()=default
	Creates a new empty BVH.
const vector< Node > &	getNodes () const noexcept
	Returns BVH node array.
const vector< uint32 > &	getPrimitives () const noexcept
	Returns BVH primitive array.
const vector< f32x4 > &	getCentroids () const noexcept
	Returns BVH centroid array.
stack< Node * > &	getNodeStack () noexcept
	Returns BVH node stack cache.
void	recreate (const uint8 *vertices, const uint8 *indices, const Aabb &rootAabb, uint32 indexCount, uint32 vertexSize, uint32 indexSize, const f32x4 *centroids=nullptr)
	Recreates BVH from the triangle array.
void	recreate (const Aabb *aabbs, const Aabb &rootAabb, uint32 aabbCount, const f32x4 *centroids=nullptr)
	Recreates BVH from the AABB array.
uint32	collectInFrustum (const Plane *planes, uint8 planeCount, uint32 *primitives, stack< Node * > *nodeStack=nullptr)
	Collects all primitives inside specified frustum.
void	traverse (const std::function< bool(const Bvh::Node &)> &isIntersected, const std::function< void(uint32, uint32)> &onLeaf)
	Traverses BVH tree.

Protected Attributes
vector< Node >	nodes
vector< uint32 >	primitives
vector< f32x4 >	centroids
stack< Node * >	nodeStack

Detailed Description

Bounding Volume Hierarchy container. (BVH tree)

A data structure commonly used in ray tracing, and collision detection to efficiently manage and process large sets of geometric objects, such as triangles or 3D models. The BVH organizes these objects into a hierarchical tree of bounding volumes (usually axis-aligned bounding boxes or spheres), allowing for faster queries related to visibility, collisions, and intersections.

Constructor & Destructor Documentation

Bvh() [1/2]

Bvh	(	const uint8 *	vertices,
		const uint8 *	indices,
		const Aabb &	rootAabb,
		uint32	indexCount,
		uint32	vertexSize,
		uint32	indexSize,
		const f32x4 *	centroids = nullptr )

Creates a new BVH from the triangle array.

Parameters

[in]	vertices	target vertex array
[in]	indices	target index array
[in]	rootAabb	root node AABB
	indexCount	index array size
	vertexSize	size of the vertex in bytes
	indexSize	size of the index in bytes
[in]	centroids	precalculated centroid array

Bvh() [2/2]

Bvh	(	const Aabb *	aabbs,
		const Aabb &	rootAabb,
		uint32	aabbCount,
		const f32x4 *	centroids = nullptr )

Creates a new BVH from the AABB array.

Parameters

[in]	aabbs	target AABB array
[in]	rootAabb	root node AABB
	aabbCount	AABB array size
[in]	centroids	precalculated centroid array

Member Function Documentation

recreate() [1/2]

void recreate	(	const uint8 *	vertices,
		const uint8 *	indices,
		const Aabb &	rootAabb,
		uint32	indexCount,
		uint32	vertexSize,
		uint32	indexSize,
		const f32x4 *	centroids = nullptr )

Recreates BVH from the triangle array.

Parameters

[in]	vertices	target vertex array
[in]	indices	target index array
[in]	rootAabb	root node AABB
	indexCount	index array size
	vertexSize	size of the vertex in bytes
	indexSize	size of the index in bytes
[in]	centroids	precalculated centroid array or null

recreate() [2/2]

void recreate	(	const Aabb *	aabbs,
		const Aabb &	rootAabb,
		uint32	aabbCount,
		const f32x4 *	centroids = nullptr )

Recreates BVH from the AABB array.

Parameters

[in]	aabbs	target AABB array
[in]	rootAabb	root node AABB
	aabbCount	AABB array size
[in]	centroids	precalculated centroid array or null

collectInFrustum()

uint32 collectInFrustum	(	const Plane *	planes,
		uint8	planeCount,
		uint32 *	primitives,
		stack< Node * > *	nodeStack = nullptr )

Collects all primitives inside specified frustum.

Parameters

[in]	planes	target frustum planes
	planeCount	frustum plane count
[out]	primitives	collected primitives array
[in]	nodeStack	local node stack or null

traverse()

void traverse ( const std::function< bool(const Bvh::Node &)> & isIntersected, const std::function< void(uint32, uint32)> & onLeaf )

inline

Traverses BVH tree.

Parameters

[in]	isIntersected	calls on each node to check for intersection
[in]	onLeaf	calls on leaf nodes to process primitives