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Add BVH module in unsupported (patch from Ilya Baran)

(I thought I committed it a week ago but it seems the command failed)
This commit is contained in:
Gael Guennebaud 2009-03-18 20:06:06 +00:00
parent 3d385ae968
commit 4bb5221d22
19 changed files with 952 additions and 6 deletions

@ -60,7 +60,7 @@ add_custom_target(
)
add_dependencies(doc-eigen-prerequisites all_snippets all_examples)
add_dependencies(doc-unsupported-prerequisites unsupported_examples)
add_dependencies(doc-unsupported-prerequisites unsupported_snippets unsupported_examples)
add_custom_target(doc ALL
COMMAND doxygen Doxyfile-unsupported
COMMAND doxygen

@ -1,4 +1,4 @@
FILE(GLOB snippets_SRCS "*.cpp" "../../unsupported/snippets/*.cpp")
FILE(GLOB snippets_SRCS "*.cpp")
ADD_CUSTOM_TARGET(all_snippets)

@ -16,4 +16,7 @@ namespace Eigen {
/** \ingroup Unsupported_modules
* \defgroup IterativeSolvers_Module Iterative solvers module */
/** \ingroup Unsupported_modules
* \defgroup BVH_Module BVH module */
} // namespace Eigen

@ -1,6 +1,8 @@
add_subdirectory(Eigen)
add_subdirectory(doc)
if(EIGEN_BUILD_TESTS)
add_subdirectory(test)
endif(EIGEN_BUILD_TESTS)

@ -167,6 +167,8 @@ protected:
};
//@}
}
#endif // EIGEN_ADLOC_FORWARD

113
unsupported/Eigen/BVH Normal file

@ -0,0 +1,113 @@
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2009 Ilya Baran <ibaran@mit.edu>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, 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.
//
// Eigen 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 Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef EIGEN_BVH_MODULE_H
#define EIGEN_BVH_MODULE_H
#include <Eigen/Core>
#include <Eigen/Geometry>
#include <Eigen/StdVector>
#include <algorithm>
#include <queue>
namespace Eigen {
/** \ingroup Unsupported_modules
* \defgroup BVH_Module BVH module
* \brief This module provides generic bounding volume hierarchy algorithms
* and reference tree implementations.
*
*
* \code
* #include <unsupported/Eigen/BVH>
* \endcode
*
* A bounding volume hierarchy (BVH) can accelerate many geometric queries. This module provides a generic implementation
* of the two basic algorithms over a BVH: intersection of a query object against all objects in the hierarchy and minimization
* of a function over the objects in the hierarchy. It also provides intersection and minimization over a cartesian product of
* two BVH's. A BVH accelerates intersection by using the fact that if a query object does not intersect a volume, then it cannot
* intersect any object contained in that volume. Similarly, a BVH accelerates minimization because the minimum of a function
* over a volume is no greater than the minimum of a function over any object contained in it.
*
* Some sample queries that can be written in terms of intersection are:
* - Determine all points where a ray intersects a triangle mesh
* - Given a set of points, determine which are contained in a query sphere
* - Given a set of spheres, determine which contain the query point
* - Given a set of spheres, determine if any is completely contained in a query box (not an intersection query,
but can still be accelerated by pruning all spheres that do not intersect the query box)
* - Given a set of points, count how many pairs are \f$d\pm\epsilon\f$ apart (done by looking at the cartesian product of the set
* of points with itself)
*
* Some sample queries that can be written in terms of function minimization over a set of objects are:
* - Find the intersection between a ray and a triangle mesh closest to the ray origin (function is infinite off the ray)
* - Given a polyline and a query point, determine the closest point on the polyline to the query
* - Find the diameter of a point cloud (done by looking at the cartesian product and using negative distance as the function)
* - Determine how far two meshes are from colliding (this is also a cartesian product query)
*
* This implementation decouples the basic algorithms both from the type of hierarchy (and the types of the bounding volumes) and
* from the particulars of the query. To enable abstraction from the BVH, the BVH is required to implement a generic mechanism
* for traversal. To abstract from the query, the query is responsible for keeping track of results.
*
* To be used in the algorithms, a hierarchy must implement the following traversal mechanism (see KdBVH for a sample implementation): \code
typedef Volume //the type of bounding volume
typedef Object //the type of object in the hierarchy
typedef Index //a reference to a node in the hierarchy--typically an int or a pointer
typedef VolumeIterator //an iterator type over node children--returns Index
typedef ObjectIterator //an iterator over object (leaf) children--returns const Object &
Index getRootIndex() const //returns the index of the hierarchy root
const Volume &getVolume(Index index) const //returns the bounding volume of the node at given index
void getChildren(Index index, VolumeIterator &outVBegin, VolumeIterator &outVEnd,
ObjectIterator &outOBegin, ObjectIterator &outOEnd) const
//getChildren takes a node index and makes [outVBegin, outVEnd) range over its node children
//and [outOBegin, outOEnd) range over its object children
\endcode
*
* To use the hierarchy, call BVIntersect or BVMinimize, passing it a BVH (or two, for cartesian product) and a minimizer or intersector.
* For an intersection query on a single BVH, the intersector encapsulates the query and must provide two functions:
* \code
bool intersectVolume(const Volume &volume) //returns true if the query intersects the volume
bool intersectObject(const Object &object) //returns true if the intersection search should terminate immediately
\endcode
* The guarantee that BVIntersect provides is that intersectObject will be called on every object whose bounding volume
* intersects the query (but possibly on other objects too) unless the search is terminated prematurely. It is the
* responsibility of the intersectObject function to keep track of the results in whatever manner is appropriate.
* The cartesian product intersection and the BVMinimize queries are similar--see their individual documentation.
*
* \addexample BVH_Example \label How to use a BVH to find the closest pair between two point sets
*
* The following is a simple but complete example for how to use the BVH to accelerate the search for a closest red-blue point pair:
* \include BVH_Example.cpp
* Output: \verbinclude BVH_Example.out
*/
//@{
#include "src/BVH/BVAlgorithms.h"
#include "src/BVH/KdBVH.h"
//@}
}
#endif // EIGEN_BVH_MODULE_H

@ -1,4 +1,4 @@
set(Eigen_HEADERS AdolcForward IterativeSolvers)
set(Eigen_HEADERS AdolcForward BVH IterativeSolvers)
install(FILES
${Eigen_HEADERS}

@ -25,6 +25,8 @@
#ifndef EIGEN_ITERATIVE_SOLVERS_MODULE_H
#define EIGEN_ITERATIVE_SOLVERS_MODULE_H
#include <Eigen/Core>
namespace Eigen {
/** \ingroup Unsupported_modules
@ -38,7 +40,7 @@ namespace Eigen {
* \endcode
*/
//@{
#include "src/IterativeSolvers/IterationController.h"
#include "src/IterativeSolvers/ConstrainedConjGrad.h"

@ -0,0 +1,276 @@
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2009 Ilya Baran <ibaran@mit.edu>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, 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.
//
// Eigen 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 Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef EIGEN_BVALGORITHMS_H
#define EIGEN_BVALGORITHMS_H
/** Given a BVH, runs the query encapsulated by \a intersector.
* The Intersector type must provide the following members: \code
bool intersectVolume(const BVH::Volume &volume) //returns true if volume intersects the query
bool intersectObject(const BVH::Object &object) //returns true if the search should terminate immediately
\endcode
*/
template<typename BVH, typename Intersector>
void BVIntersect(const BVH &tree, Intersector &intersector)
{
ei_intersect_helper(tree, intersector, tree.getRootIndex());
}
#ifndef EIGEN_PARSED_BY_DOXYGEN
template<typename BVH, typename Intersector>
bool ei_intersect_helper(const BVH &tree, Intersector &intersector, typename BVH::Index root)
{
typedef typename BVH::Index Index;
typename BVH::VolumeIterator vBegin, vEnd;
typename BVH::ObjectIterator oBegin, oEnd;
std::vector<Index> todo(1, root);
while(!todo.empty()) {
tree.getChildren(todo.back(), vBegin, vEnd, oBegin, oEnd);
todo.pop_back();
for(; vBegin != vEnd; ++vBegin) //go through child volumes
if(intersector.intersectVolume(tree.getVolume(*vBegin)))
todo.push_back(*vBegin);
for(; oBegin != oEnd; ++oBegin) //go through child objects
if(intersector.intersectObject(*oBegin))
return true; //intersector said to stop query
}
return false;
}
#endif //not EIGEN_PARSED_BY_DOXYGEN
template<typename Volume1, typename Object1, typename Object2, typename Intersector>
struct ei_intersector_helper1
{
ei_intersector_helper1(const Object2 &inStored, Intersector &in) : stored(inStored), intersector(in) {}
bool intersectVolume(const Volume1 &vol) { return intersector.intersectVolumeObject(vol, stored); }
bool intersectObject(const Object1 &obj) { return intersector.intersectObjectObject(obj, stored); }
Object2 stored;
Intersector &intersector;
};
template<typename Volume2, typename Object2, typename Object1, typename Intersector>
struct ei_intersector_helper2
{
ei_intersector_helper2(const Object1 &inStored, Intersector &in) : stored(inStored), intersector(in) {}
bool intersectVolume(const Volume2 &vol) { return intersector.intersectObjectVolume(stored, vol); }
bool intersectObject(const Object2 &obj) { return intersector.intersectObjectObject(stored, obj); }
Object1 stored;
Intersector &intersector;
};
/** Given two BVH's, runs the query on their cartesian product encapsulated by \a intersector.
* The Intersector type must provide the following members: \code
bool intersectVolumeVolume(const BVH1::Volume &v1, const BVH2::Volume &v2) //returns true if product of volumes intersects the query
bool intersectVolumeObject(const BVH1::Volume &v1, const BVH2::Object &o2) //returns true if the volume-object product intersects the query
bool intersectObjectVolume(const BVH1::Object &o1, const BVH2::Volume &v2) //returns true if the volume-object product intersects the query
bool intersectObjectObject(const BVH1::Object &o1, const BVH2::Object &o2) //returns true if the search should terminate immediately
\endcode
*/
template<typename BVH1, typename BVH2, typename Intersector>
void BVIntersect(const BVH1 &tree1, const BVH2 &tree2, Intersector &intersector) //TODO: tandem descent when it makes sense
{
typedef typename BVH1::Index Index1;
typedef typename BVH2::Index Index2;
typedef ei_intersector_helper1<typename BVH1::Volume, typename BVH1::Object, typename BVH2::Object, Intersector> Helper1;
typedef ei_intersector_helper2<typename BVH2::Volume, typename BVH2::Object, typename BVH1::Object, Intersector> Helper2;
typename BVH1::VolumeIterator vBegin1, vEnd1;
typename BVH1::ObjectIterator oBegin1, oEnd1;
typename BVH2::VolumeIterator vBegin2, vEnd2, vCur2;
typename BVH2::ObjectIterator oBegin2, oEnd2, oCur2;
std::vector<std::pair<Index1, Index2> > todo(1, std::make_pair(tree1.getRootIndex(), tree2.getRootIndex()));
while(!todo.empty()) {
tree1.getChildren(todo.back().first, vBegin1, vEnd1, oBegin1, oEnd1);
tree2.getChildren(todo.back().second, vBegin2, vEnd2, oBegin2, oEnd2);
todo.pop_back();
for(; vBegin1 != vEnd1; ++vBegin1) { //go through child volumes of first tree
const typename BVH1::Volume &vol1 = tree1.getVolume(*vBegin1);
for(vCur2 = vBegin2; vCur2 != vEnd2; ++vCur2) { //go through child volumes of second tree
if(intersector.intersectVolumeVolume(vol1, tree2.getVolume(*vCur2)))
todo.push_back(std::make_pair(*vBegin1, *vCur2));
}
for(oCur2 = oBegin2; oCur2 != oEnd2; ++oCur2) {//go through child objects of second tree
Helper1 helper(*oCur2, intersector);
if(ei_intersect_helper(tree1, helper, *vBegin1))
return; //intersector said to stop query
}
}
for(; oBegin1 != oEnd1; ++oBegin1) { //go through child objects of first tree
for(vCur2 = vBegin2; vCur2 != vEnd2; ++vCur2) { //go through child volumes of second tree
Helper2 helper(*oBegin1, intersector);
if(ei_intersect_helper(tree2, helper, *vCur2))
return; //intersector said to stop query
}
for(oCur2 = oBegin2; oCur2 != oEnd2; ++oCur2) {//go through child objects of second tree
if(intersector.intersectObjectObject(*oBegin1, *oCur2))
return; //intersector said to stop query
}
}
}
}
/** Given a BVH, runs the query encapsulated by \a minimizer.
* \returns the minimum value.
* The Minimizer type must provide the following members: \code
typedef Scalar //the numeric type of what is being minimized--not necessarily the Scalar type of the BVH (if it has one)
Scalar minimumOnVolume(const BVH::Volume &volume)
Scalar minimumOnObject(const BVH::Object &object)
\endcode
*/
template<typename BVH, typename Minimizer>
typename Minimizer::Scalar BVMinimize(const BVH &tree, Minimizer &minimizer)
{
return ei_minimize_helper(tree, minimizer, tree.getRootIndex(), std::numeric_limits<typename Minimizer::Scalar>::max());
}
#ifndef EIGEN_PARSED_BY_DOXYGEN
template<typename BVH, typename Minimizer>
typename Minimizer::Scalar ei_minimize_helper(const BVH &tree, Minimizer &minimizer, typename BVH::Index root, typename Minimizer::Scalar minimum)
{
typedef typename Minimizer::Scalar Scalar;
typedef typename BVH::Index Index;
typedef std::pair<Scalar, Index> QueueElement; //first element is priority
typename BVH::VolumeIterator vBegin, vEnd;
typename BVH::ObjectIterator oBegin, oEnd;
std::priority_queue<QueueElement, std::vector<QueueElement>, std::greater<QueueElement> > todo; //smallest is at the top
todo.push(std::make_pair(Scalar(), root));
while(!todo.empty()) {
tree.getChildren(todo.top().second, vBegin, vEnd, oBegin, oEnd);
todo.pop();
for(; oBegin != oEnd; ++oBegin) //go through child objects
minimum = std::min(minimum, minimizer.minimumOnObject(*oBegin));
for(; vBegin != vEnd; ++vBegin) { //go through child volumes
Scalar val = minimizer.minimumOnVolume(tree.getVolume(*vBegin));
if(val < minimum)
todo.push(std::make_pair(val, *vBegin));
}
}
return minimum;
}
#endif //not EIGEN_PARSED_BY_DOXYGEN
template<typename Volume1, typename Object1, typename Object2, typename Minimizer>
struct ei_minimizer_helper1
{
typedef typename Minimizer::Scalar Scalar;
ei_minimizer_helper1(const Object2 &inStored, Minimizer &m) : stored(inStored), minimizer(m) {}
Scalar minimumOnVolume(const Volume1 &vol) { return minimizer.minimumOnVolumeObject(vol, stored); }
Scalar minimumOnObject(const Object1 &obj) { return minimizer.minimumOnObjectObject(obj, stored); }
Object2 stored;
Minimizer &minimizer;
};
template<typename Volume2, typename Object2, typename Object1, typename Minimizer>
struct ei_minimizer_helper2
{
typedef typename Minimizer::Scalar Scalar;
ei_minimizer_helper2(const Object1 &inStored, Minimizer &m) : stored(inStored), minimizer(m) {}
Scalar minimumOnVolume(const Volume2 &vol) { return minimizer.minimumOnObjectVolume(stored, vol); }
Scalar minimumOnObject(const Object2 &obj) { return minimizer.minimumOnObjectObject(stored, obj); }
Object1 stored;
Minimizer &minimizer;
};
/** Given two BVH's, runs the query on their cartesian product encapsulated by \a minimizer.
* \returns the minimum value.
* The Minimizer type must provide the following members: \code
typedef Scalar //the numeric type of what is being minimized--not necessarily the Scalar type of the BVH (if it has one)
Scalar minimumOnVolumeVolume(const BVH1::Volume &v1, const BVH2::Volume &v2)
Scalar minimumOnVolumeObject(const BVH1::Volume &v1, const BVH2::Object &o2)
Scalar minimumOnObjectVolume(const BVH1::Object &o1, const BVH2::Volume &v2)
Scalar minimumOnObjectObject(const BVH1::Object &o1, const BVH2::Object &o2)
\endcode
*/
template<typename BVH1, typename BVH2, typename Minimizer>
typename Minimizer::Scalar BVMinimize(const BVH1 &tree1, const BVH2 &tree2, Minimizer &minimizer)
{
typedef typename Minimizer::Scalar Scalar;
typedef typename BVH1::Index Index1;
typedef typename BVH2::Index Index2;
typedef ei_minimizer_helper1<typename BVH1::Volume, typename BVH1::Object, typename BVH2::Object, Minimizer> Helper1;
typedef ei_minimizer_helper2<typename BVH2::Volume, typename BVH2::Object, typename BVH1::Object, Minimizer> Helper2;
typedef std::pair<Scalar, std::pair<Index1, Index2> > QueueElement; //first element is priority
typename BVH1::VolumeIterator vBegin1, vEnd1;
typename BVH1::ObjectIterator oBegin1, oEnd1;
typename BVH2::VolumeIterator vBegin2, vEnd2, vCur2;
typename BVH2::ObjectIterator oBegin2, oEnd2, oCur2;
std::priority_queue<QueueElement, std::vector<QueueElement>, std::greater<QueueElement> > todo; //smallest is at the top
Scalar minimum = std::numeric_limits<Scalar>::max();
todo.push(std::make_pair(Scalar(), std::make_pair(tree1.getRootIndex(), tree2.getRootIndex())));
while(!todo.empty()) {
tree1.getChildren(todo.top().second.first, vBegin1, vEnd1, oBegin1, oEnd1);
tree2.getChildren(todo.top().second.second, vBegin2, vEnd2, oBegin2, oEnd2);
todo.pop();
for(; oBegin1 != oEnd1; ++oBegin1) { //go through child objects of first tree
for(oCur2 = oBegin2; oCur2 != oEnd2; ++oCur2) {//go through child objects of second tree
minimum = std::min(minimum, minimizer.minimumOnObjectObject(*oBegin1, *oCur2));
}
for(vCur2 = vBegin2; vCur2 != vEnd2; ++vCur2) { //go through child volumes of second tree
Helper2 helper(*oBegin1, minimizer);
minimum = std::min(minimum, ei_minimize_helper(tree2, helper, *vCur2, minimum));
}
}
for(; vBegin1 != vEnd1; ++vBegin1) { //go through child volumes of first tree
const typename BVH1::Volume &vol1 = tree1.getVolume(*vBegin1);
for(oCur2 = oBegin2; oCur2 != oEnd2; ++oCur2) {//go through child objects of second tree
Helper1 helper(*oCur2, minimizer);
minimum = std::min(minimum, ei_minimize_helper(tree1, helper, *vBegin1, minimum));
}
for(vCur2 = vBegin2; vCur2 != vEnd2; ++vCur2) { //go through child volumes of second tree
Scalar val = minimizer.minimumOnVolumeVolume(vol1, tree2.getVolume(*vCur2));
if(val < minimum)
todo.push(std::make_pair(val, std::make_pair(*vBegin1, *vCur2)));
}
}
}
return minimum;
}
#endif // EIGEN_BVALGORITHMS_H

@ -0,0 +1,6 @@
FILE(GLOB Eigen_BVH_SRCS "*.h")
INSTALL(FILES
${Eigen_BVH_SRCS}
DESTINATION ${INCLUDE_INSTALL_DIR}/unsupported/Eigen/src/BVH COMPONENT Devel
)

@ -0,0 +1,225 @@
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2009 Ilya Baran <ibaran@mit.edu>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, 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.
//
// Eigen 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 Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef KDBVH_H_INCLUDED
#define KDBVH_H_INCLUDED
//internal pair class for the BVH--used instead of std::pair because of alignment
template<typename Scalar, int Dim>
struct ei_vector_int_pair
{
EIGEN_MAKE_ALIGNED_OPERATOR_NEW_IF_VECTORIZABLE_FIXED_SIZE(Scalar, Dim)
typedef Matrix<Scalar, Dim, 1> VectorType;
ei_vector_int_pair(const VectorType &v, int i) : first(v), second(i) {}
VectorType first;
int second;
};
//these templates help the tree initializer get the bounding boxes either from a provided
//iterator range or using ei_bounding_box in a unified way
template<typename Object, typename Volume, typename BoxIter>
struct ei_get_boxes_helper {
void operator()(const std::vector<Object> &objects, BoxIter boxBegin, BoxIter boxEnd, std::vector<Volume> &outBoxes)
{
outBoxes.insert(outBoxes.end(), boxBegin, boxEnd);
ei_assert(outBoxes.size() == objects.size());
}
};
template<typename Object, typename Volume>
struct ei_get_boxes_helper<Object, Volume, int> {
void operator()(const std::vector<Object> &objects, int, int, std::vector<Volume> &outBoxes)
{
outBoxes.reserve(objects.size());
for(int i = 0; i < (int)objects.size(); ++i)
outBoxes.push_back(ei_bounding_box(objects[i]));
}
};
/** \class KdBVH
* \brief A simple bounding volume hierarchy based on AlignedBox
*
* \param _Scalar The underlying scalar type of the bounding boxes
* \param _Dim The dimension of the space in which the hierarchy lives
* \param _Object The object type that lives in the hierarchy. It must have value semantics. Either ei_bounding_box(_Object) must
* be defined and return an AlignedBox<_Scalar, _Dim> or bounding boxes must be provided to the tree initializer.
*
* This class provides a simple (as opposed to optimized) implementation of a bounding volume hierarchy analogous to a Kd-tree.
* Given a sequence of objects, it computes their bounding boxes, constructs a Kd-tree of their centers
* and builds a BVH with the structure of that Kd-tree. When the elements of the tree are too expensive to be copied around,
* it is useful for _Object to be a pointer.
*/
template<typename _Scalar, int _Dim, typename _Object> class KdBVH
{
public:
enum { Dim = _Dim };
typedef _Object Object;
typedef _Scalar Scalar;
typedef AlignedBox<Scalar, Dim> Volume;
typedef int Index;
typedef const int *VolumeIterator; //the iterators are just pointers into the tree's vectors
typedef const Object *ObjectIterator;
KdBVH() {}
/** Given an iterator range over \a Object references, constructs the BVH. Requires that ei_bounding_box(Object) return a Volume. */
template<typename Iter> KdBVH(Iter begin, Iter end) { init(begin, end, 0, 0); } //int is recognized by init as not being an iterator type
/** Given an iterator range over \a Object references and an iterator range over their bounding boxes, constructs the BVH */
template<typename OIter, typename BIter> KdBVH(OIter begin, OIter end, BIter boxBegin, BIter boxEnd) { init(begin, end, boxBegin, boxEnd); }
/** Given an iterator range over \a Object references, constructs the BVH, overwriting whatever is in there currently.
* Requires that ei_bounding_box(Object) return a Volume. */
template<typename Iter> void init(Iter begin, Iter end) { init(begin, end, 0, 0); }
/** Given an iterator range over \a Object references and an iterator range over their bounding boxes,
* constructs the BVH, overwriting whatever is in there currently. */
template<typename OIter, typename BIter> void init(OIter begin, OIter end, BIter boxBegin, BIter boxEnd)
{
objects.clear();
boxes.clear();
children.clear();
objects.insert(objects.end(), begin, end);
int n = objects.size();
if(n < 2)
return; //if we have at most one object, we don't need any internal nodes
std::vector<Volume> objBoxes;
std::vector<VIPair> objCenters;
ei_get_boxes_helper<Object, Volume, BIter>()(objects, boxBegin, boxEnd, objBoxes); //compute the bounding boxes depending on BIter type
objCenters.reserve(n);
boxes.reserve(n - 1);
children.reserve(2 * n - 2);
for(int i = 0; i < n; ++i)
objCenters.push_back(VIPair(objBoxes[i].center(), i));
build(objCenters, 0, n, objBoxes, 0); //the recursive part of the algorithm
std::vector<Object> tmp(n);
tmp.swap(objects);
for(int i = 0; i < n; ++i)
objects[i] = tmp[objCenters[i].second];
}
/** \returns the index of the root of the hierarchy */
inline Index getRootIndex() const { return (int)boxes.size() - 1; }
/** Given an \a index of a node, on exit, \a outVBegin and \a outVEnd range over the indices of the volume children of the node
* and \a outOBegin and \a outOEnd range over the object children of the node */
EIGEN_STRONG_INLINE void getChildren(Index index, VolumeIterator &outVBegin, VolumeIterator &outVEnd,
ObjectIterator &outOBegin, ObjectIterator &outOEnd) const
{ //inlining this function should open lots of optimization opportunities to the compiler
if(index < 0) {
outVBegin = outVEnd;
if(!objects.empty())
outOBegin = &(objects[0]);
outOEnd = outOBegin + objects.size(); //output all objects--necessary when the tree has only one object
return;
}
int numBoxes = boxes.size();
int idx = index * 2;
if(children[idx + 1] < numBoxes) { //second index is always bigger
outVBegin = &(children[idx]);
outVEnd = outVBegin + 2;
outOBegin = outOEnd;
}
else if(children[idx] >= numBoxes) { //if both children are objects
outVBegin = outVEnd;
outOBegin = &(objects[children[idx] - numBoxes]);
outOEnd = outOBegin + 2;
} else { //if the first child is a volume and the second is an object
outVBegin = &(children[idx]);
outVEnd = outVBegin + 1;
outOBegin = &(objects[children[idx + 1] - numBoxes]);
outOEnd = outOBegin + 1;
}
}
/** \returns the bounding box of the node at \a index */
inline const Volume &getVolume(Index index) const
{
return boxes[index];
}
private:
typedef ei_vector_int_pair<Scalar, Dim> VIPair;
typedef Matrix<Scalar, Dim, 1> VectorType;
struct VectorComparator //compares vectors, or, more specificall, VIPairs along a particular dimension
{
VectorComparator(int inDim) : dim(inDim) {}
inline bool operator()(const VIPair &v1, const VIPair &v2) const { return v1.first[dim] < v2.first[dim]; }
int dim;
};
//Build the part of the tree between objects[from] and objects[to] (not including objects[to]).
//This routine partitions the objCenters in [from, to) along the dimension dim, recursively constructs
//the two halves, and adds their parent node. TODO: a cache-friendlier layout
void build(std::vector<VIPair> &objCenters, int from, int to, const std::vector<Volume> &objBoxes, int dim)
{
ei_assert(to - from > 1);
if(to - from == 2) {
boxes.push_back(objBoxes[objCenters[from].second].merged(objBoxes[objCenters[from + 1].second]));
children.push_back(from + (int)objects.size() - 1); //there are objects.size() - 1 tree nodes
children.push_back(from + (int)objects.size());
}
else if(to - from == 3) {
int mid = from + 2;
std::nth_element(objCenters.begin() + from, objCenters.begin() + mid,
objCenters.begin() + to, VectorComparator(dim)); //partition
build(objCenters, from, mid, objBoxes, (dim + 1) % Dim);
int idx1 = (int)boxes.size() - 1;
boxes.push_back(boxes[idx1].merged(objBoxes[objCenters[mid].second]));
children.push_back(idx1);
children.push_back(mid + (int)objects.size() - 1);
}
else {
int mid = from + (to - from) / 2;
nth_element(objCenters.begin() + from, objCenters.begin() + mid,
objCenters.begin() + to, VectorComparator(dim)); //partition
build(objCenters, from, mid, objBoxes, (dim + 1) % Dim);
int idx1 = (int)boxes.size() - 1;
build(objCenters, mid, to, objBoxes, (dim + 1) % Dim);
int idx2 = (int)boxes.size() - 1;
boxes.push_back(boxes[idx1].merged(boxes[idx2]));
children.push_back(idx1);
children.push_back(idx2);
}
}
std::vector<int> children; //children of x are children[2x] and children[2x+1], indices bigger than boxes.size() index into objects.
std::vector<Volume> boxes;
std::vector<Object> objects;
};
#endif //KDBVH_H_INCLUDED

@ -1 +1,2 @@
ADD_SUBDIRECTORY(IterativeSolvers)
ADD_SUBDIRECTORY(BVH)

@ -0,0 +1,2 @@
add_subdirectory(examples)

@ -626,7 +626,11 @@ EXCLUDE_SYMBOLS = MatrixBase<* MapBase<* RotationBase<* Matrix<*
EXAMPLE_PATH = "${Eigen_SOURCE_DIR}/doc/snippets" \
"${Eigen_BINARY_DIR}/doc/snippets" \
"${Eigen_SOURCE_DIR}/doc/examples" \
"${Eigen_BINARY_DIR}/doc/examples"
"${Eigen_BINARY_DIR}/doc/examples" \
"${Eigen_SOURCE_DIR}/unsupported/doc/snippets" \
"${Eigen_BINARY_DIR}/unsupported/doc/snippets" \
"${Eigen_SOURCE_DIR}/unsupported/doc/examples" \
"${Eigen_BINARY_DIR}/unsupported/doc/examples"
# If the value of the EXAMPLE_PATH tag contains directories, you can use the
# EXAMPLE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp

@ -0,0 +1,45 @@
#include <unsupported/Eigen/BVH>
using namespace Eigen;
typedef AlignedBox<double, 2> Box2d;
Box2d ei_bounding_box(const Vector2d &v) { return Box2d(v, v); } //compute the bounding box of a single point
struct PointPointMinimizer //how to compute squared distances between points and rectangles
{
PointPointMinimizer() : calls(0) {}
typedef double Scalar;
double minimumOnVolumeVolume(const Box2d &r1, const Box2d &r2) { ++calls; return r1.squaredExteriorDistance(r2); }
double minimumOnVolumeObject(const Box2d &r, const Vector2d &v) { ++calls; return r.squaredExteriorDistance(v); }
double minimumOnObjectVolume(const Vector2d &v, const Box2d &r) { ++calls; return r.squaredExteriorDistance(v); }
double minimumOnObjectObject(const Vector2d &v1, const Vector2d &v2) { ++calls; return (v1 - v2).squaredNorm(); }
int calls;
};
int main()
{
std::vector<Vector2d> redPoints, bluePoints;
for(int i = 0; i < 100; ++i) { //initialize random set of red points and blue points
redPoints.push_back(Vector2d::Random());
bluePoints.push_back(Vector2d::Random());
}
PointPointMinimizer minimizer;
double minDistSq = std::numeric_limits<double>::max();
//brute force to find closest red-blue pair
for(int i = 0; i < (int)redPoints.size(); ++i)
for(int j = 0; j < (int)bluePoints.size(); ++j)
minDistSq = std::min(minDistSq, minimizer.minimumOnObjectObject(redPoints[i], bluePoints[j]));
std::cout << "Brute force distance = " << sqrt(minDistSq) << ", calls = " << minimizer.calls << std::endl;
//using BVH to find closest red-blue pair
minimizer.calls = 0;
KdBVH<double, 2, Vector2d> redTree(redPoints.begin(), redPoints.end()), blueTree(bluePoints.begin(), bluePoints.end()); //construct the trees
minDistSq = BVMinimize(redTree, blueTree, minimizer); //actual BVH minimization call
std::cout << "BVH distance = " << sqrt(minDistSq) << ", calls = " << minimizer.calls << std::endl;
return 0;
}

@ -0,0 +1,17 @@
FILE(GLOB examples_SRCS "*.cpp")
ADD_CUSTOM_TARGET(unsupported_examples)
FOREACH(example_src ${examples_SRCS})
GET_FILENAME_COMPONENT(example ${example_src} NAME_WE)
ADD_EXECUTABLE(${example} ${example_src})
GET_TARGET_PROPERTY(example_executable
${example} LOCATION)
ADD_CUSTOM_COMMAND(
TARGET ${example}
POST_BUILD
COMMAND ${example_executable}
ARGS >${CMAKE_CURRENT_BINARY_DIR}/${example}.out
)
ADD_DEPENDENCIES(unsupported_examples ${example})
ENDFOREACH(example_src)

@ -0,0 +1,25 @@
FILE(GLOB snippets_SRCS "*.cpp")
ADD_CUSTOM_TARGET(unsupported_snippets)
FOREACH(snippet_src ${snippets_SRCS})
GET_FILENAME_COMPONENT(snippet ${snippet_src} NAME_WE)
SET(compile_snippet_target compile_${snippet})
SET(compile_snippet_src ${compile_snippet_target}.cpp)
FILE(READ ${snippet_src} snippet_source_code)
CONFIGURE_FILE(${PROJECT_SOURCE_DIR}/doc/compile_snippet.cpp.in
${CMAKE_CURRENT_BINARY_DIR}/${compile_snippet_src})
ADD_EXECUTABLE(${compile_snippet_target}
${CMAKE_CURRENT_BINARY_DIR}/${compile_snippet_src})
GET_TARGET_PROPERTY(compile_snippet_executable
${compile_snippet_target} LOCATION)
ADD_CUSTOM_COMMAND(
TARGET ${compile_snippet_target}
POST_BUILD
COMMAND ${compile_snippet_executable}
ARGS >${CMAKE_CURRENT_BINARY_DIR}/${snippet}.out
)
ADD_DEPENDENCIES(unsupported_snippets ${compile_snippet_target})
set_source_files_properties(${CMAKE_CURRENT_BINARY_DIR}/${compile_snippet_src}
PROPERTIES OBJECT_DEPENDS ${snippet_src})
ENDFOREACH(snippet_src)

221
unsupported/test/BVH.cpp Normal file

@ -0,0 +1,221 @@
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2009 Ilya Baran <ibaran@mit.edu>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, 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.
//
// Eigen 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 Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#include <Eigen/StdVector>
#include "main.h"
#include <unsupported/Eigen/BVH>
inline double SQR(double x) { return x * x; }
template<int Dim>
struct Ball
{
EIGEN_MAKE_ALIGNED_OPERATOR_NEW_IF_VECTORIZABLE_FIXED_SIZE(double, Dim)
typedef Matrix<double, Dim, 1> VectorType;
Ball() {}
Ball(const VectorType &c, double r) : center(c), radius(r) {}
VectorType center;
double radius;
};
template<int Dim> AlignedBox<double, Dim> ei_bounding_box(const Matrix<double, Dim, 1> &v) { return AlignedBox<double, Dim>(v); }
template<int Dim> AlignedBox<double, Dim> ei_bounding_box(const Ball<Dim> &b)
{ return AlignedBox<double, Dim>(b.center.cwise() - b.radius, b.center.cwise() + b.radius); }
template<int Dim>
struct BallPointStuff //this class provides functions to be both an intersector and a minimizer, both for a ball and a point and for two trees
{
typedef double Scalar;
typedef Matrix<double, Dim, 1> VectorType;
typedef Ball<Dim> BallType;
typedef AlignedBox<double, Dim> BoxType;
BallPointStuff() : calls(0), count(0) {}
BallPointStuff(const VectorType &inP) : p(inP), calls(0), count(0) {}
bool intersectVolume(const BoxType &r) { ++calls; return r.contains(p); }
bool intersectObject(const BallType &b) {
++calls;
if((b.center - p).squaredNorm() < SQR(b.radius))
++count;
return false; //continue
}
bool intersectVolumeVolume(const BoxType &r1, const BoxType &r2) { ++calls; return !(r1.intersection(r2)).isNull(); }
bool intersectVolumeObject(const BoxType &r, const BallType &b) { ++calls; return r.squaredExteriorDistance(b.center) < SQR(b.radius); }
bool intersectObjectVolume(const BallType &b, const BoxType &r) { ++calls; return r.squaredExteriorDistance(b.center) < SQR(b.radius); }
bool intersectObjectObject(const BallType &b1, const BallType &b2){
++calls;
if((b1.center - b2.center).norm() < b1.radius + b2.radius)
++count;
return false;
}
bool intersectVolumeObject(const BoxType &r, const VectorType &v) { ++calls; return r.contains(v); }
bool intersectObjectObject(const BallType &b, const VectorType &v){
++calls;
if((b.center - v).squaredNorm() < SQR(b.radius))
++count;
return false;
}
double minimumOnVolume(const BoxType &r) { ++calls; return r.squaredExteriorDistance(p); }
double minimumOnObject(const BallType &b) { ++calls; return std::max(0., (b.center - p).squaredNorm() - SQR(b.radius)); }
double minimumOnVolumeVolume(const BoxType &r1, const BoxType &r2) { ++calls; return r1.squaredExteriorDistance(r2); }
double minimumOnVolumeObject(const BoxType &r, const BallType &b) { ++calls; return SQR(std::max(0., r.exteriorDistance(b.center) - b.radius)); }
double minimumOnObjectVolume(const BallType &b, const BoxType &r) { ++calls; return SQR(std::max(0., r.exteriorDistance(b.center) - b.radius)); }
double minimumOnObjectObject(const BallType &b1, const BallType &b2){ ++calls; return SQR(std::max(0., (b1.center - b2.center).norm() - b1.radius - b2.radius)); }
double minimumOnVolumeObject(const BoxType &r, const VectorType &v) { ++calls; return r.squaredExteriorDistance(v); }
double minimumOnObjectObject(const BallType &b, const VectorType &v){ ++calls; return SQR(std::max(0., (b.center - v).norm() - b.radius)); }
VectorType p;
int calls;
int count;
};
template<int Dim>
struct TreeTest
{
typedef Matrix<double, Dim, 1> VectorType;
typedef Ball<Dim> BallType;
typedef AlignedBox<double, Dim> BoxType;
void testIntersect1()
{
std::vector<BallType> b;
for(int i = 0; i < 500; ++i) {
b.push_back(BallType(VectorType::Random(), 0.5 * ei_random(0., 1.)));
}
KdBVH<double, Dim, BallType> tree(b.begin(), b.end());
VectorType pt = VectorType::Random();
BallPointStuff<Dim> i1(pt), i2(pt);
for(int i = 0; i < (int)b.size(); ++i)
i1.intersectObject(b[i]);
BVIntersect(tree, i2);
VERIFY(i1.count == i2.count);
}
void testMinimize1()
{
std::vector<BallType> b;
for(int i = 0; i < 500; ++i) {
b.push_back(BallType(VectorType::Random(), 0.01 * ei_random(0., 1.)));
}
KdBVH<double, Dim, BallType> tree(b.begin(), b.end());
VectorType pt = VectorType::Random();
BallPointStuff<Dim> i1(pt), i2(pt);
double m1 = std::numeric_limits<double>::max(), m2 = m1;
for(int i = 0; i < (int)b.size(); ++i)
m1 = std::min(m1, i1.minimumOnObject(b[i]));
m2 = BVMinimize(tree, i2);
VERIFY_IS_APPROX(m1, m2);
}
void testIntersect2()
{
std::vector<BallType> b;
std::vector<VectorType> v;
for(int i = 0; i < 50; ++i) {
b.push_back(BallType(VectorType::Random(), 0.5 * ei_random(0., 1.)));
for(int j = 0; j < 3; ++j)
v.push_back(VectorType::Random());
}
KdBVH<double, Dim, BallType> tree(b.begin(), b.end());
KdBVH<double, Dim, VectorType> vTree(v.begin(), v.end());
BallPointStuff<Dim> i1, i2;
for(int i = 0; i < (int)b.size(); ++i)
for(int j = 0; j < (int)v.size(); ++j)
i1.intersectObjectObject(b[i], v[j]);
BVIntersect(tree, vTree, i2);
VERIFY(i1.count == i2.count);
}
void testMinimize2()
{
std::vector<BallType> b;
std::vector<VectorType> v;
for(int i = 0; i < 50; ++i) {
b.push_back(BallType(VectorType::Random(), 1e-7 + 1e-6 * ei_random(0., 1.)));
for(int j = 0; j < 3; ++j)
v.push_back(VectorType::Random());
}
KdBVH<double, Dim, BallType> tree(b.begin(), b.end());
KdBVH<double, Dim, VectorType> vTree(v.begin(), v.end());
BallPointStuff<Dim> i1, i2;
double m1 = std::numeric_limits<double>::max(), m2 = m1;
for(int i = 0; i < (int)b.size(); ++i)
for(int j = 0; j < (int)v.size(); ++j)
m1 = std::min(m1, i1.minimumOnObjectObject(b[i], v[j]));
m2 = BVMinimize(tree, vTree, i2);
VERIFY_IS_APPROX(m1, m2);
}
};
void test_BVH()
{
for(int i = 0; i < g_repeat; i++) {
TreeTest<2> test2;
CALL_SUBTEST(test2.testIntersect1());
CALL_SUBTEST(test2.testMinimize1());
CALL_SUBTEST(test2.testIntersect2());
CALL_SUBTEST(test2.testMinimize2());
TreeTest<3> test3;
CALL_SUBTEST(test3.testIntersect1());
CALL_SUBTEST(test3.testMinimize1());
CALL_SUBTEST(test3.testIntersect2());
CALL_SUBTEST(test3.testMinimize2());
TreeTest<4> test4;
CALL_SUBTEST(test4.testIntersect1());
CALL_SUBTEST(test4.testMinimize1());
CALL_SUBTEST(test4.testIntersect2());
CALL_SUBTEST(test4.testMinimize2());
}
}

@ -13,4 +13,6 @@ if(ADOLC_FOUND)
ei_add_test(forward_adolc " " ${ADOLC_LIBRARIES})
else(ADOLC_FOUND)
ei_add_property(EIGEN_MISSING_BACKENDS "Adolc")
endif(ADOLC_FOUND)
endif(ADOLC_FOUND)
ei_add_test(BVH)