vcglib/vcg/space/index/octree.h

793 lines
24 KiB
C++

/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004 \/)\/ *
* Visual Computing Lab /\/| *
* ISTI - Italian National Research Council | *
* \ *
* All rights reserved. *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License (http://www.gnu.org/licenses/gpl.txt) *
* for more details. *
* *
****************************************************************************/
#ifndef VCG_SPACE_INDEX_OCTREE_H
#define VCG_SPACE_INDEX_OCTREE_H
#include <stdlib.h>
#include <algorithm>
#include <vector>
#include <iterator>
#ifdef __glut_h__
#include <vcg/space/color4.h>
#include <wrap/gl/space.h>
#endif
#include <vcg/space/index/base.h>
#include <vcg/space/index/octree_template.h>
#include <vcg/space/box3.h>
#include <wrap/callback.h>
namespace vcg
{
/*!
* Given an object or an object pointer, return the reference to the object
*/
template <typename TYPE>
struct Dereferencer
{
static TYPE& Ref(TYPE &t) { return ( t); }
static TYPE& Ref(TYPE* &t) { return (*t); }
static const TYPE& Ref(const TYPE &t) { return ( t); }
static const TYPE& Ref(const TYPE* &t) { return (*t); }
};
/*!
* Given a type, return the type
*/
template <typename T>
class ReferenceType
{
public:
typedef T Type;
};
/*!
* Given as type a pointer to type, return the type
*/
template <typename T>
class ReferenceType<T *>
{
public:
typedef typename ReferenceType<T>::Type Type;
};
/*!
* The type of the octree voxels
*/
struct Voxel
{
Voxel() { count = begin = end = -1; }
void SetRange(const int begin, const int end)
{
this->begin = begin;
this->end = end;
count = end-begin;
};
void AddRange(const Voxel *voxel)
{
assert(voxel->end>end);
count += voxel->count;
end = voxel->end;
};
int begin;
int end;
int count;
};
template < class OBJECT_TYPE, class SCALAR_TYPE>
class Octree : public vcg::OctreeTemplate< Voxel, SCALAR_TYPE >, public vcg::SpatialIndex< OBJECT_TYPE, SCALAR_TYPE >
{
protected:
struct Neighbour;
public:
typedef SCALAR_TYPE ScalarType;
typedef OBJECT_TYPE ObjectType;
typedef typename Octree::Leaf * LeafPointer;
typedef typename Octree::InnerNode * InnerNodePointer;
typedef typename ReferenceType<OBJECT_TYPE>::Type * ObjectPointer;
typedef vcg::Voxel VoxelType;
typedef VoxelType * VoxelPointer;
typedef vcg::OctreeTemplate< VoxelType, SCALAR_TYPE > TemplatedOctree;
typedef typename TemplatedOctree::ZOrderType ZOrderType;
typedef typename TemplatedOctree::BoundingBoxType BoundingBoxType;
typedef typename TemplatedOctree::CenterType CenterType;
typedef typename TemplatedOctree::CoordinateType CoordType;
typedef typename TemplatedOctree::NodeType NodeType;
typedef typename TemplatedOctree::NodePointer NodePointer;
typedef typename TemplatedOctree::NodeIndex NodeIndex;
typedef typename std::vector< Neighbour >::iterator NeighbourIterator;
protected:
/***********************************************
* INNER DATA STRUCTURES AND PREDICATES *
***********************************************/
/*!
* Structure used during the sorting of the dataset
*/
template < typename LEAF_TYPE >
struct ObjectPlaceholder
{
typedef LEAF_TYPE* LeafPointer;
ObjectPlaceholder() { z_order = object_index = -1, leaf_pointer = NULL;}
ObjectPlaceholder(ZOrderType zOrder, void* leafPointer, unsigned int objectIndex)
{
z_order = zOrder;
leaf_pointer = leafPointer;
object_index = objectIndex;
}
ZOrderType z_order;
LeafPointer leaf_pointer;
unsigned int object_index;
};
/*!
* Predicate used during the sorting of the dataset
*/
template <typename LEAF_TYPE >
struct ObjectSorter
{
inline bool operator()(const ObjectPlaceholder< LEAF_TYPE > &first, const ObjectPlaceholder< LEAF_TYPE > &second)
{
return (first.z_order<second.z_order);
}
};
/*!
* Structure which holds the reference to the object and the position of the mark for that object
*/
struct ObjectReference
{
ObjectReference() {pMark=NULL; pObject=NULL;}
unsigned char *pMark;
ObjectPointer pObject;
};
/*
* The generic item in the neighbors vector computed by GetNearestNeighbors;
*/
struct Neighbour
{
Neighbour()
{
this->object = NULL;
this->distance = -1.0f;
};
Neighbour(ObjectPointer &object, CoordType &point, ScalarType distance)
{
this->object = object;
this->point = point;
this->distance = distance;
}
inline bool operator<(const Neighbour &n) const
{
return distance<n.distance;
}
ObjectPointer object;
CoordType point;
ScalarType distance;
};
public:
Octree()
{
marks=0;
}
~Octree()
{
if(marks) delete []marks;
int node_count = TemplatedOctree::NodeCount();
for (int i=0; i<node_count; i++)
delete TemplatedOctree::nodes[i];
TemplatedOctree::nodes.clear();
}
/*!
* Populate the octree
*/
template < class OBJECT_ITERATOR >
void Set(const OBJECT_ITERATOR & bObj, const OBJECT_ITERATOR & eObj /*, vcg::CallBackPos *callback=NULL*/)
{
// Compute the bounding-box enclosing the whole dataset
typedef Dereferencer<typename ReferenceType<typename OBJECT_ITERATOR::value_type>::Type > DereferencerType;
BoundingBoxType bounding_box, obj_bb;
bounding_box.SetNull();
for (OBJECT_ITERATOR iObj=bObj; iObj!=eObj; iObj++)
{
(*iObj).GetBBox(obj_bb);
bounding_box.Add(obj_bb);
}
//...and expand it a bit more
BoundingBoxType resulting_bb(bounding_box);
CoordType offset = bounding_box.Dim()*Octree::EXPANSION_FACTOR;
CoordType center = bounding_box.Center();
resulting_bb.Offset(offset);
ScalarType longest_side = vcg::math::Max( resulting_bb.DimX(), resulting_bb.DimY(), resulting_bb.DimZ())/2.0f;
resulting_bb.Set(center);
resulting_bb.Offset(longest_side);
TemplatedOctree::boundingBox = resulting_bb;
// Try to find a reasonable octree depth
int dataset_dimension = int(std::distance(bObj, eObj));
int primitives_per_voxel;
int depth = 4;
do
{
int number_of_voxel = 1<<(3*depth); // i.e. 8^depth
float density = float(number_of_voxel)/float(depth);
primitives_per_voxel = int(float(dataset_dimension)/density);
depth++;
}
while (primitives_per_voxel>25 && depth<15);
TemplatedOctree::Initialize(++depth);
// Sort the dataset (using the lebesgue space filling curve...)
std::string message("Indexing dataset...");
NodePointer *route = new NodePointer[depth+1];
OBJECT_ITERATOR iObj = bObj;
//if (callback!=NULL) callback(int((i+1)*100/dataset_dimension), message.c_str());
std::vector< ObjectPlaceholder< NodeType > > placeholders/*(dataset_dimension)*/;
vcg::Box3<ScalarType> object_bb;
vcg::Point3<ScalarType> hit_leaf;
for (int i=0; i<dataset_dimension; i++, iObj++)
{
(*iObj).GetBBox(object_bb);
hit_leaf = object_bb.min;
while (object_bb.IsIn(hit_leaf))
{
int placeholder_index = int(placeholders.size());
placeholders.push_back( ObjectPlaceholder< NodeType >() );
placeholders[placeholder_index].z_order = BuildRoute(hit_leaf, route);
placeholders[placeholder_index].leaf_pointer = route[depth];
placeholders[placeholder_index].object_index = i;
hit_leaf.X() += TemplatedOctree::leafDimension.X();
if (hit_leaf.X()>object_bb.max.X())
{
hit_leaf.X() = object_bb.min.X();
hit_leaf.Z()+= TemplatedOctree::leafDimension.Z();
if (hit_leaf.Z()>object_bb.max.Z())
{
hit_leaf.Z() = object_bb.min.Z();
hit_leaf.Y()+= TemplatedOctree::leafDimension.Y();
}
}
}
}
delete []route;
int placeholder_count = int(placeholders.size());
// Allocate the mark array
global_mark = 1;
marks = new unsigned char[placeholder_count];
memset(&marks[0], 0, sizeof(unsigned char)*placeholder_count);
std::sort(placeholders.begin(), placeholders.end(), ObjectSorter< NodeType >());
std::vector< NodePointer > filled_leaves(placeholder_count);
sorted_dataset.resize( placeholder_count );
for (int i=0; i<placeholder_count; i++)
{
std::advance((iObj=bObj), placeholders[i].object_index);
sorted_dataset[i].pObject = &DereferencerType::Ref(*iObj);
sorted_dataset[i].pMark = &marks[i];
filled_leaves[i] = placeholders[i].leaf_pointer;
}
// The dataset is sorted and the octree is built, but the indexing information aren't stored yet in the octree:
// we assign to each leaf the range inside the sorted dataset of the primitives contained inside the leaf
int begin = -1;
NodePointer initial_leaf = NULL;
for (int end=0; end<placeholder_count; )
{
begin = end;
initial_leaf = filled_leaves[begin];
do end++;
while (end<placeholder_count && initial_leaf==filled_leaves[end]);
VoxelType *voxel = TemplatedOctree::Voxel(initial_leaf);
voxel->SetRange(begin, end);
}
// The octree is built, the dataset is sorted but only the leaves are indexed:
// we propagate the indexing information bottom-up to the root
IndexInnerNodes( TemplatedOctree::Root() );
} //end of Set
/*!
* Finds the closest object to a given point.
*/
template <class OBJECT_POINT_DISTANCE_FUNCTOR, class OBJECT_MARKER>
ObjectPointer GetClosest
(
OBJECT_POINT_DISTANCE_FUNCTOR & distance_functor,
OBJECT_MARKER & /*marker*/,
const CoordType & query_point,
const ScalarType & max_distance,
ScalarType & distance,
CoordType & point,
bool allow_zero_distance = true
)
{
BoundingBoxType query_bb;
ScalarType sphere_radius;
if (!GuessInitialBoundingBox(query_point, max_distance, sphere_radius, query_bb))
return NULL;
std::vector< NodePointer > leaves;
//unsigned int object_count;
//int leaves_count;
IncrementMark();
AdjustBoundingBox(query_bb, sphere_radius, max_distance, leaves, 1);
if (sphere_radius>max_distance)
return NULL;
std::vector< Neighbour > neighbors;
RetrieveContainedObjects(query_point, distance_functor, max_distance, allow_zero_distance, leaves, neighbors);
typename std::vector< Neighbour >::iterator first = neighbors.begin();
typename std::vector< Neighbour >::iterator last = neighbors.end();
std::partial_sort(first, first+1, last);
distance = neighbors[0].distance;
point = neighbors[0].point;
return neighbors[0].object;
}; //end of GetClosest
/*!
* Retrieve the k closest element to the query point
*/
template <class OBJECT_POINT_DISTANCE_FUNCTOR, class OBJECT_MARKER, class OBJECT_POINTER_CONTAINER, class DISTANCE_CONTAINER, class POINT_CONTAINER>
unsigned int GetKClosest
(
OBJECT_POINT_DISTANCE_FUNCTOR & distance_functor,
OBJECT_MARKER & /*marker*/,
unsigned int k,
const CoordType & query_point,
const ScalarType & max_distance,
OBJECT_POINTER_CONTAINER & objects,
DISTANCE_CONTAINER & distances,
POINT_CONTAINER & points,
bool sort_per_distance = true,
bool allow_zero_distance = true
)
{
BoundingBoxType query_bb;
ScalarType sphere_radius;
if (!GuessInitialBoundingBox(query_point, max_distance, sphere_radius, query_bb))
return 0;
std::vector< NodePointer > leaves;
std::vector< Neighbour > neighbors;
unsigned int object_count;
float k_distance;
OBJECT_RETRIEVER:
IncrementMark();
AdjustBoundingBox(query_bb, sphere_radius, max_distance, leaves, k);
object_count = RetrieveContainedObjects(query_point, distance_functor, max_distance, allow_zero_distance, leaves, neighbors);
if (sphere_radius<max_distance && object_count<k)
goto OBJECT_RETRIEVER;
NeighbourIterator first = neighbors.begin();
NeighbourIterator last = neighbors.end();
object_count = std::min(k, object_count);
if (sort_per_distance) std::partial_sort< NeighbourIterator >(first, first+object_count, last );
else std::nth_element < NeighbourIterator >(first, first+object_count, last );
k_distance = neighbors[object_count-1].distance;
if (k_distance>sphere_radius && sphere_radius<max_distance)
goto OBJECT_RETRIEVER;
return CopyQueryResults<OBJECT_POINTER_CONTAINER, DISTANCE_CONTAINER, POINT_CONTAINER>(neighbors, object_count, objects, distances, points);
}; //end of GetKClosest
/*!
* Returns all the objects contained inside a specified sphere
*/
template <class OBJECT_POINT_DISTANCE_FUNCTOR, class OBJECT_MARKER, class OBJECT_POINTER_CONTAINER, class DISTANCE_CONTAINER, class POINT_CONTAINER>
unsigned int GetInSphere
(
OBJECT_POINT_DISTANCE_FUNCTOR &distance_functor,
OBJECT_MARKER &/*marker*/,
const CoordType &sphere_center,
const ScalarType &sphere_radius,
OBJECT_POINTER_CONTAINER &objects,
DISTANCE_CONTAINER &distances,
POINT_CONTAINER &points,
bool sort_per_distance = false,
bool allow_zero_distance = false
)
{
// Define the minimum bounding-box containing the sphere
BoundingBoxType query_bb(sphere_center, sphere_radius);
// If that bounding-box don't collide with the octree bounding-box, simply return 0
if (!TemplatedOctree::boundingBox.Collide(query_bb))
return 0;
std::vector< NodePointer > leaves;
std::vector< Neighbour > neighbors;
IncrementMark();
ContainedLeaves(query_bb, leaves, TemplatedOctree::Root(), TemplatedOctree::boundingBox);
int leaves_count = int(leaves.size());
if (leaves_count==0)
return 0;
int object_count = RetrieveContainedObjects(sphere_center, distance_functor, sphere_radius, allow_zero_distance, leaves, neighbors);
NeighbourIterator first = neighbors.begin();
NeighbourIterator last = neighbors.end();
if (sort_per_distance) std::partial_sort< NeighbourIterator >(first, first+object_count, last );
else std::nth_element < NeighbourIterator >(first, first+object_count, last );
return CopyQueryResults<OBJECT_POINTER_CONTAINER, DISTANCE_CONTAINER, POINT_CONTAINER>(neighbors, object_count, objects, distances, points);
};//end of GetInSphere
/*!
* Returns all the objects lying inside the specified bbox
*/
template <class OBJECT_MARKER, class OBJECT_POINTER_CONTAINER>
unsigned int GetInBox
(
OBJECT_MARKER &/*marker*/,
const BoundingBoxType &query_bounding_box,
OBJECT_POINTER_CONTAINER &objects
)
{
//if the query bounding-box don't collide with the octree bounding-box, simply return 0
if (!query_bounding_box.Collide())
{
objects.clear();
return 0;
}
//otherwise, retrieve the leaves and fill the container with the objects contained
std::vector< NodePointer > leaves;
unsigned int object_count;
int leaves_count;
TemplatedOctree::ContainedLeaves(query_bounding_box, leaves, TemplatedOctree::Root(), TemplatedOctree::boundingBox);
leaves_count = int(leaves.size());
if (leaves_count==0)
return 0;
IncrementMark();
for (int i=0; i<leaves_count; i++)
{
VoxelType *voxel = TemplatedOctree::Voxel(leaves[i]);
int begin = voxel->begin;
int end = voxel->end;
for ( ; begin<end; begin++)
{
ObjectReference *ref = &sorted_dataset[begin];
if (IsMarked(ref))
continue;
Mark(ref);
objects.push_back(ref->pObject);
} //end of for ( ; begin<end; begin++)
} // end of for (int i=0; i<leavesCount; i++)
return int(objects.size());
}; //end of GetInBox
protected:
/*!
* Contains pointer to the objects in the dataset.
* The pointers are sorted so that the object pointed to result ordered in the space
*/
std::vector< ObjectReference > sorted_dataset;
/*!
* Markers used to avoid duplication of the same result during a query
*/
unsigned char *marks;
unsigned char global_mark;
/*!
* The expansion factor used to solve the spatial queries
* The current expansion factor is computed on the basis of the last expansion factor
* and on the history of these values, through the following heuristic:
* current_expansion_factor = alpha*last_expansion_factor + (1.0f-alpha)*mean_expansion_factor
* where alpha = 1.0/3.0;
*/
//float last_expansion_factor;
//float mean_expansion_factor;
//float ALPHA;
//float ONE_MINUS_ALPHA;
protected:
/*!
*/
inline void IncrementMark()
{
// update the marks
global_mark = (global_mark+1)%255;
if (global_mark == 0)
{
memset(&marks[0], 0, sizeof(unsigned char)*int(sorted_dataset.size()));
global_mark++;
}
};//end of IncrementMark
/*
*/
inline bool IsMarked(const ObjectReference *ref) const
{ return *ref->pMark == global_mark; };
/*
*/
inline void Mark(const ObjectReference *ref)
{ *ref->pMark = global_mark;};
/*!
* Guess an initial bounding-box from which starting the research of the closest point(s).
* \return true iff it's possibile to find a sphere, centered in query_point and having radius max_distance at most, which collide the octree bounding-box.
*/
inline bool GuessInitialBoundingBox(const CoordType &query_point, const ScalarType max_distance, ScalarType &sphere_radius, BoundingBoxType &query_bb)
{
// costruisco una bounging box centrata in query di dimensione pari a quella di una foglia.
// e controllo se in tale bounging box sono contenute un numero di elementi >= a k.
// Altrimenti espando il bounding box.
query_bb.Set(query_point);
// the radius of the sphere centered in query
sphere_radius = 0.0f;
// if the bounding-box doesn't intersect the bounding-box of the octree, then it must be immediately expanded
if (!query_bb.IsIn(query_point))
{
do
{
query_bb.Offset(TemplatedOctree::leafDiagonal);
sphere_radius += TemplatedOctree::leafDiagonal;
}
while ( !TemplatedOctree::boundingBox.Collide(query_bb) || sphere_radius>max_distance);
}
return (sphere_radius<=max_distance);
};
/*!
* Modify the bounding-box used during the query until either at least k points
* are contained inside the box or the box radius became greater than the threshold distance
* Return the number of leaves contained inside the bounding-box
*/
inline int AdjustBoundingBox
(
BoundingBoxType & query_bb,
ScalarType & sphere_radius,
const ScalarType max_allowed_distance,
std::vector< NodePointer > & leaves,
const int required_object_count
)
{
int leaves_count;
int object_count;
do
{
leaves.clear();
query_bb.Offset(TemplatedOctree::leafDiagonal);
sphere_radius+= TemplatedOctree::leafDiagonal;
ContainedLeaves(query_bb, leaves, TemplatedOctree::Root(), TemplatedOctree::boundingBox);
leaves_count = int(leaves.size());
object_count = 0;
for (int i=0; i<leaves_count; i++)
object_count += TemplatedOctree::Voxel( leaves[i] )->count;
}
while (object_count<required_object_count && sphere_radius<max_allowed_distance);
return leaves_count;
}
/*!
* Retrieves the objects contained inside the leaves whose distance isn't greater than max_distance.
* Returns the number of valid objects
*/
template < class OBJECT_POINT_DISTANCE_FUNCTOR >
inline int RetrieveContainedObjects
(
const CoordType query_point,
OBJECT_POINT_DISTANCE_FUNCTOR & distance_functor,
const ScalarType max_allowed_distance,
bool allow_zero_distance,
std::vector< NodePointer > & leaves,
std::vector< Neighbour > & neighbors
)
{
CoordType closest_point;
neighbors.clear();
for (int i=0, leaves_count=int(leaves.size()); i<leaves_count; i++)
{
VoxelType *voxel = TemplatedOctree::Voxel(leaves[i]);
int begin = voxel->begin;
int end = voxel->end;
for ( ; begin<end; begin++)
{
ObjectReference * ref = &sorted_dataset[begin];
if (IsMarked(ref))
continue;
ScalarType distance = max_allowed_distance;
if (!distance_functor(*ref->pObject, query_point, distance, closest_point))
continue;
Mark(ref);
if ((distance!=ScalarType(0.0) || allow_zero_distance))
neighbors.push_back( Neighbour(ref->pObject, closest_point, distance) );
} //end of for ( ; begin<end; begin++)
} // end of for (int i=0; i<leavesCount; i++)
return int(neighbors.size());
};
/*!
* Copy the results of a query
*/
template <class OBJECT_POINTER_CONTAINER, class DISTANCE_CONTAINER, class POINT_CONTAINER>
inline int CopyQueryResults
(
std::vector< Neighbour > &neighbors,
const unsigned int object_count,
OBJECT_POINTER_CONTAINER &objects,
DISTANCE_CONTAINER &distances,
POINT_CONTAINER &points
)
{
// copy the nearest object into
points.resize( object_count );
distances.resize( object_count );
objects.resize( object_count );
typename POINT_CONTAINER::iterator iPoint = points.begin();
typename DISTANCE_CONTAINER::iterator iDistance = distances.begin();
typename OBJECT_POINTER_CONTAINER::iterator iObject = objects.begin();
for (unsigned int n=0; n<object_count; n++, iPoint++, iDistance++, iObject++)
{
(*iPoint) = neighbors[n].point;
(*iDistance) = neighbors[n].distance;
(*iObject) = neighbors[n].object;
}
return object_count;
}
/*!
* When all the leaves are indexed, this procedure is called in order to propagate the indexing information to the inner nodes
*/
void IndexInnerNodes(NodePointer n)
{
assert(n!=NULL);
VoxelPointer current_voxel = TemplatedOctree::Voxel(n);
VoxelPointer son_voxel;
for (int s=0; s<8; s++)
{
NodePointer son_index = Son(n, s);
if (son_index!=NULL)
{
if (Level(son_index)!=TemplatedOctree::maximumDepth)
IndexInnerNodes(son_index);
son_voxel = TemplatedOctree::Voxel(son_index);
current_voxel->AddRange( son_voxel );
}
}
}; // end of IndexInnerNodes
};
#ifdef __glut_h__
/************************************************************************/
/* Rendering */
/************************************************************************/
protected:
/*!
* Structure which holds the rendering settings
*/
struct OcreeRenderingSetting
{
OcreeRenderingSetting()
{
color = vcg::Color4b(155, 155, 155, 255);
isVisible = false;
minVisibleDepth = 1;
maxVisibleDepth = 4;
};
int isVisible;
int minVisibleDepth;
int maxVisibleDepth;
vcg::Color4b color;
};
public:
/*
* Draw the octree in a valid OpenGL context according to the rendering settings
*/
void DrawOctree(vcg::Box3f &boundingBox, NodePointer n)
{
char level = TemplatedOctree::Level(n);
NodePointer son;
if (rendering_settings.minVisibleDepth>level)
{
for (int s=0; s<8; s++)
if ((son=Son(n, s))!=0)
DrawOctree(TemplatedOctree::SubBox(boundingBox, s), son);
}
else
{
vcg::glBoxWire(boundingBox);
if (level<rendering_settings.maxVisibleDepth)
for (int s=0; s<8; s++)
if ((son=Son(n, s))!=0)
DrawOctree(TemplatedOctree::SubBox(boundingBox, s), son);
}
};
OcreeRenderingSetting rendering_settings;
#endif
} //end of namespace vcg
#endif //VCG_SPACE_INDEX_OCTREE_H