SLCompactGrid Class Reference

Class for compact uniform grid acceleration structure. More...

#include <SLCompactGrid.h>

Inheritance diagram for SLCompactGrid:

Public Types
using	Triangle = std::array< SLVec3f, 3 >

Public Member Functions
	SLCompactGrid (SLMesh *m)
	~SLCompactGrid ()
void	build (SLVec3f minV, SLVec3f maxV)
void	updateStats (SLNodeStats &stats)
	Updates the statistics in the parent node. More...
void	draw (SLSceneView *sv)
	SLCompactGrid::draw draws the non-empty voxels of the uniform grid. More...
SLbool	intersect (SLRay *ray, SLNode *node)
void	deleteAll ()
	Deletes the entire uniform grid data. More...
void	disposeBuffers ()
SLuint	indexAtPos (const SLVec3i &p) const
SLVec3f	voxelCenter (const SLVec3i &pos) const
	Returns the voxel center point for a given voxel by index. More...
SLVec3i	containingVoxel (const SLVec3f &p) const
	Returns the indices of the voxel around a given point. More...
void	getMinMaxVoxel (const Triangle &triangle, SLVec3i &minCell, SLVec3i &maxCell)
	Returns the min. and max. voxel of a triangle. More...
void	ifTriangleInVoxelDo (triVoxCallback cb)
	Loops over triangles gets their voxels and calls the callback function. More...
Public Member Functions inherited from SLAccelStruct
	SLAccelStruct (SLMesh *m)
virtual	~SLAccelStruct ()
virtual void	build (SLVec3f minV, SLVec3f maxV)=0
virtual void	updateStats (SLNodeStats &stats)=0
virtual void	draw (SLSceneView *sv)=0
virtual SLbool	intersect (SLRay *ray, SLNode *node)=0
virtual void	disposeBuffers ()=0

Private Attributes
SLVec3ui	_size
	num. of voxel in grid dir. More...
SLuint	_numTriangles
	NO. of triangles in the mesh. More...
SLVec3f	_voxelSize
	size of a voxel More...
SLVec3f	_voxelSizeHalf
	half size of a voxel More...
SLVuint	_voxelOffsets
	Offset array (C in the paper) More...
SLVushort	_triangleIndexes16
	16 bit triangle index array (L in the paper) More...
SLVuint	_triangleIndexes32
	32 bit triangle index array (L in the paper) More...
SLGLVertexArrayExt	_vao
	Vertex array object for rendering. More...

Additional Inherited Members
Protected Attributes inherited from SLAccelStruct
SLMesh *	_m
	Pointer to the mesh. More...
SLVec3f	_minV
	min. point of AABB More...
SLVec3f	_maxV
	max. point of AABB More...
SLuint	_voxelCnt
	NO. of voxels in accelerator. More...
SLuint	_voxelCntEmpty
	NO. of empty voxels. More...
SLuint	_voxelMaxTria
	max. no. of triangles pre voxel More...
SLfloat	_voxelAvgTria
	avg. no. of triangles per voxel More...

Detailed Description

Class for compact uniform grid acceleration structure.

This class implements the data structure proposed by Lagae & Dutre in their paper "Compact, Fast and Robust Grids for Ray Tracing". It reduces the memory footprint to 20% of a regular uniform grid implemented in SLUniformGrid.

Member Typedef Documentation

Triangle

using SLCompactGrid::Triangle = std::array<SLVec3f, 3>

Constructor & Destructor Documentation

SLCompactGrid()

SLCompactGrid::SLCompactGrid

(

SLMesh *

m

)

~SLCompactGrid()

SLCompactGrid::~SLCompactGrid ( )

inline

Member Function Documentation

build()

void SLCompactGrid::build ( SLVec3f  minV, SLVec3f  maxV  )

virtual

SLCompactGrid::build implements the data structure proposed by Lagae & Dutre in their paper "Compact, Fast and Robust Grids for Ray Tracing".

Implements SLAccelStruct.

containingVoxel()

SLVec3i SLCompactGrid::containingVoxel

(

const SLVec3f &

p

)

const

Returns the indices of the voxel around a given point.

deleteAll()

void SLCompactGrid::deleteAll

(

)

Deletes the entire uniform grid data.

disposeBuffers()

void SLCompactGrid::disposeBuffers ( )

inlinevirtual

Implements SLAccelStruct.

draw()

void SLCompactGrid::draw ( SLSceneView *  sv )

virtual

SLCompactGrid::draw draws the non-empty voxels of the uniform grid.

Implements SLAccelStruct.

getMinMaxVoxel()

void SLCompactGrid::getMinMaxVoxel	(	const Triangle &	triangle,
		SLVec3i &	minCell,
		SLVec3i &	maxCell
	)

Returns the min. and max. voxel of a triangle.

ifTriangleInVoxelDo()

void SLCompactGrid::ifTriangleInVoxelDo

(

triVoxCallback

cb

)

Loops over triangles gets their voxels and calls the callback function.

indexAtPos()

SLuint SLCompactGrid::indexAtPos ( const SLVec3i &  p ) const

inline

intersect()

SLbool SLCompactGrid::intersect ( SLRay *  ray, SLNode *  node  )

virtual

Ray Mesh intersection method using the regular grid space subdivision structure and a voxel traversal algorithm described in "A Fast Voxel Traversal Algorithm for Ray Tracing" by John Amanatides and Andrew Woo.

Implements SLAccelStruct.

updateStats()

void SLCompactGrid::updateStats ( SLNodeStats &  stats )

virtual

Updates the statistics in the parent node.

Implements SLAccelStruct.

voxelCenter()

SLVec3f SLCompactGrid::voxelCenter

(

const SLVec3i &

pos

)

const

Returns the voxel center point for a given voxel by index.

Member Data Documentation

_numTriangles

SLuint SLCompactGrid::_numTriangles

private

NO. of triangles in the mesh.

_size

SLVec3ui SLCompactGrid::_size

private

num. of voxel in grid dir.

_triangleIndexes16

SLVushort SLCompactGrid::_triangleIndexes16

private

16 bit triangle index array (L in the paper)

_triangleIndexes32

SLVuint SLCompactGrid::_triangleIndexes32

private

32 bit triangle index array (L in the paper)

_vao

SLGLVertexArrayExt SLCompactGrid::_vao

private

Vertex array object for rendering.

_voxelOffsets

SLVuint SLCompactGrid::_voxelOffsets

private

Offset array (C in the paper)

_voxelSize

SLVec3f SLCompactGrid::_voxelSize

private

size of a voxel

_voxelSizeHalf

SLVec3f SLCompactGrid::_voxelSizeHalf

private

half size of a voxel

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

• SLCompactGrid.h
• SLCompactGrid.cpp