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flightgear/src/Navaids/positioned.cxx

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// positioned.cxx - base class for objects which are positioned
//
// Copyright (C) 2008 James Turner
//
// 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "positioned.hxx"
#include <map>
#include <set>
#include <algorithm> // for sort
#include <queue>
#include <boost/algorithm/string/case_conv.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <osg/Math> // for osg::isNaN
#include <simgear/timing/timestamp.hxx>
#include <simgear/debug/logstream.hxx>
#include <simgear/structure/exception.hxx>
#include <simgear/math/SGGeometry.hxx>
typedef std::multimap<std::string, FGPositioned*> NamedPositionedIndex;
typedef std::pair<NamedPositionedIndex::const_iterator, NamedPositionedIndex::const_iterator> NamedIndexRange;
using std::lower_bound;
using std::upper_bound;
static NamedPositionedIndex global_identIndex;
static NamedPositionedIndex global_nameIndex;
//////////////////////////////////////////////////////////////////////////////
namespace Octree
{
const double LEAF_SIZE = SG_NM_TO_METER * 8.0;
const double LEAF_SIZE_SQR = LEAF_SIZE * LEAF_SIZE;
/**
* Decorate an object with a double value, and use that value to order
* items, for the purpoises of the STL algorithms
*/
template <class T>
class Ordered
{
public:
Ordered(const T& v, double x) :
_order(x),
_inner(v)
{
}
Ordered(const Ordered<T>& a) :
_order(a._order),
_inner(a._inner)
{
}
Ordered<T>& operator=(const Ordered<T>& a)
{
_order = a._order;
_inner = a._inner;
return *this;
}
bool operator<(const Ordered<T>& other) const
{
return _order < other._order;
}
bool operator>(const Ordered<T>& other) const
{
return _order > other._order;
}
const T& get() const
{ return _inner; }
double order() const
{ return _order; }
private:
double _order;
T _inner;
};
class Node;
typedef Ordered<Node*> OrderedNode;
typedef std::greater<OrderedNode> FNPQCompare;
/**
* the priority queue is fundamental to our search algorithm. When searching,
* we know the front of the queue is the nearest unexpanded node (to the search
* location). The default STL pqueue returns the 'largest' item from top(), so
* to get the smallest, we need to replace the default Compare functor (less<>)
* with greater<>.
*/
typedef std::priority_queue<OrderedNode, std::vector<OrderedNode>, FNPQCompare> FindNearestPQueue;
typedef Ordered<FGPositioned*> OrderedPositioned;
typedef std::vector<OrderedPositioned> FindNearestResults;
Node* global_spatialOctree = NULL;
/**
* Octree node base class, tracks its bounding box and provides various
* queries relating to it
*/
class Node
{
public:
bool contains(const SGVec3d& aPos) const
{
return intersects(aPos, _box);
}
double distSqrToNearest(const SGVec3d& aPos) const
{
return distSqr(aPos, _box.getClosestPoint(aPos));
}
virtual void insert(FGPositioned* aP) = 0;
virtual void visit(const SGVec3d& aPos, double aCutoff,
FGPositioned::Filter* aFilter,
FindNearestResults& aResults, FindNearestPQueue&) = 0;
protected:
Node(const SGBoxd &aBox) :
_box(aBox)
{
}
const SGBoxd _box;
};
class Leaf : public Node
{
public:
Leaf(const SGBoxd& aBox) :
Node(aBox)
{
}
const FGPositioned::List& members() const
{ return _members; }
virtual void insert(FGPositioned* aP)
{
_members.push_back(aP);
}
virtual void visit(const SGVec3d& aPos, double aCutoff,
FGPositioned::Filter* aFilter,
FindNearestResults& aResults, FindNearestPQueue&)
{
int previousResultsSize = aResults.size();
int addedCount = 0;
for (unsigned int i=0; i<_members.size(); ++i) {
FGPositioned* p = _members[i];
double d2 = distSqr(aPos, p->cart());
if (d2 > aCutoff) {
continue;
}
if (aFilter) {
if (aFilter->hasTypeRange() && !aFilter->passType(p->type())) {
continue;
}
if (!aFilter->pass(p)) {
continue;
}
} // of have a filter
++addedCount;
aResults.push_back(OrderedPositioned(p, d2));
}
if (addedCount == 0) {
return;
}
// keep aResults sorted
// sort the new items, usually just one or two items
std::sort(aResults.begin() + previousResultsSize, aResults.end());
// merge the two sorted ranges together - in linear time
std::inplace_merge(aResults.begin(),
aResults.begin() + previousResultsSize, aResults.end());
}
private:
FGPositioned::List _members;
};
class Branch : public Node
{
public:
Branch(const SGBoxd& aBox) :
Node(aBox)
{
memset(children, 0, sizeof(Node*) * 8);
}
virtual void insert(FGPositioned* aP)
{
SGVec3d cart(aP->cart());
assert(contains(cart));
int childIndex = 0;
SGVec3d center(_box.getCenter());
// tests must match indices in SGbox::getCorner
if (cart.x() < center.x()) {
childIndex += 1;
}
if (cart.y() < center.y()) {
childIndex += 2;
}
if (cart.z() < center.z()) {
childIndex += 4;
}
Node* child = children[childIndex];
if (!child) { // lazy building of children
SGBoxd cb(boxForChild(childIndex));
double d2 = dot(cb.getSize(), cb.getSize());
if (d2 < LEAF_SIZE_SQR) {
child = new Leaf(cb);
} else {
child = new Branch(cb);
}
children[childIndex] = child;
}
child->insert(aP);
}
virtual void visit(const SGVec3d& aPos, double aCutoff,
FGPositioned::Filter*,
FindNearestResults&, FindNearestPQueue& aQ)
{
for (unsigned int i=0; i<8; ++i) {
if (!children[i]) {
continue;
}
double d2 = children[i]->distSqrToNearest(aPos);
if (d2 > aCutoff) {
continue; // exceeded cutoff
}
aQ.push(Ordered<Node*>(children[i], d2));
} // of child iteration
}
private:
/**
* Return the box for a child touching the specified corner
*/
SGBoxd boxForChild(unsigned int aCorner) const
{
SGBoxd r(_box.getCenter());
r.expandBy(_box.getCorner(aCorner));
return r;
}
Node* children[8];
};
void findNearestN(const SGVec3d& aPos, unsigned int aN, double aCutoffM, FGPositioned::Filter* aFilter, FGPositioned::List& aResults)
{
aResults.clear();
FindNearestPQueue pq;
FindNearestResults results;
pq.push(Ordered<Node*>(global_spatialOctree, 0));
double cut = aCutoffM * aCutoffM;
while (!pq.empty()) {
if (!results.empty()) {
// terminate the search if we have sufficent results, and we are
// sure no node still on the queue contains a closer match
double furthestResultOrder = results.back().order();
if ((results.size() >= aN) && (furthestResultOrder < pq.top().order())) {
break;
}
}
Node* nd = pq.top().get();
pq.pop();
nd->visit(aPos, cut, aFilter, results, pq);
} // of queue iteration
// depending on leaf population, we may have (slighty) more results
// than requested
unsigned int numResults = std::min((unsigned int) results.size(), aN);
// copy results out
aResults.resize(numResults);
for (unsigned int r=0; r<numResults; ++r) {
aResults[r] = results[r].get();
}
}
void findAllWithinRange(const SGVec3d& aPos, double aRangeM, FGPositioned::Filter* aFilter, FGPositioned::List& aResults)
{
aResults.clear();
FindNearestPQueue pq;
FindNearestResults results;
pq.push(Ordered<Node*>(global_spatialOctree, 0));
double rng = aRangeM * aRangeM;
while (!pq.empty()) {
Node* nd = pq.top().get();
pq.pop();
nd->visit(aPos, rng, aFilter, results, pq);
} // of queue iteration
unsigned int numResults = results.size();
// copy results out
aResults.resize(numResults);
for (unsigned int r=0; r<numResults; ++r) {
aResults[r] = results[r].get();
}
}
} // of namespace Octree
//////////////////////////////////////////////////////////////////////////////
static void
addToIndices(FGPositioned* aPos)
{
assert(aPos);
if (!aPos->ident().empty()) {
std::string u(boost::to_upper_copy(aPos->ident()));
global_identIndex.insert(global_identIndex.begin(),
std::make_pair(u, aPos));
}
if (!aPos->name().empty()) {
std::string u(boost::to_upper_copy(aPos->name()));
global_nameIndex.insert(global_nameIndex.begin(),
std::make_pair(u, aPos));
}
if (!Octree::global_spatialOctree) {
double RADIUS_EARTH_M = 7000 * 1000.0; // 7000km is plenty
SGVec3d earthExtent(RADIUS_EARTH_M, RADIUS_EARTH_M, RADIUS_EARTH_M);
Octree::global_spatialOctree = new Octree::Branch(SGBox<double>(-earthExtent, earthExtent));
}
Octree::global_spatialOctree->insert(aPos);
}
static void
removeFromIndices(FGPositioned* aPos)
{
assert(aPos);
if (!aPos->ident().empty()) {
std::string u(boost::to_upper_copy(aPos->ident()));
NamedPositionedIndex::iterator it = global_identIndex.find(u);
while (it != global_identIndex.end() && (it->first == u)) {
if (it->second == aPos) {
global_identIndex.erase(it);
break;
}
++it;
} // of multimap walk
}
if (!aPos->name().empty()) {
std::string u(boost::to_upper_copy(aPos->name()));
NamedPositionedIndex::iterator it = global_nameIndex.find(u);
while (it != global_nameIndex.end() && (it->first == u)) {
if (it->second == aPos) {
global_nameIndex.erase(it);
break;
}
++it;
} // of multimap walk
}
}
//////////////////////////////////////////////////////////////////////////////
class OrderByName
{
public:
bool operator()(FGPositioned* a, FGPositioned* b) const
{
return a->name() < b->name();
}
};
void findInIndex(NamedPositionedIndex& aIndex, const std::string& aFind, std::vector<FGPositioned*>& aResult)
{
NamedPositionedIndex::const_iterator it = aIndex.begin();
NamedPositionedIndex::const_iterator end = aIndex.end();
bool haveFilter = !aFind.empty();
for (; it != end; ++it) {
FGPositioned::Type ty = it->second->type();
if ((ty < FGPositioned::AIRPORT) || (ty > FGPositioned::SEAPORT)) {
continue;
}
if (haveFilter && it->first.find(aFind) == std::string::npos) {
continue;
}
aResult.push_back(it->second);
} // of index iteration
}
/**
* A special purpose helper (imported by FGAirport::searchNamesAndIdents) to
* implement the AirportList dialog. It's unfortunate that it needs to reside
* here, but for now it's least ugly solution.
*/
char** searchAirportNamesAndIdents(const std::string& aFilter)
{
// note this is a vector of raw pointers, not smart pointers, because it
// may get very large and smart-pointer-atomicity-locking then becomes a
// bottleneck for this case.
std::vector<FGPositioned*> matches;
if (!aFilter.empty()) {
std::string filter = boost::to_upper_copy(aFilter);
findInIndex(global_identIndex, filter, matches);
findInIndex(global_nameIndex, filter, matches);
} else {
findInIndex(global_identIndex, std::string(), matches);
}
// sort alphabetically on name
std::sort(matches.begin(), matches.end(), OrderByName());
// convert results to format comptible with puaList
unsigned int numMatches = matches.size();
char** result = new char*[numMatches + 1];
result[numMatches] = NULL; // end-of-list marker
// nasty code to avoid excessive string copying and allocations.
// We format results as follows (note whitespace!):
// ' name-of-airport-chars (ident)'
// so the total length is:
// 1 + strlen(name) + 4 + strlen(icao) + 1 + 1 (for the null)
// which gives a grand total of 7 + name-length + icao-length.
// note the ident can be three letters (non-ICAO local strip), four
// (default ICAO) or more (extended format ICAO)
for (unsigned int i=0; i<numMatches; ++i) {
int nameLength = matches[i]->name().size();
int icaoLength = matches[i]->ident().size();
char* entry = new char[7 + nameLength + icaoLength];
char* dst = entry;
*dst++ = ' ';
memcpy(dst, matches[i]->name().c_str(), nameLength);
dst += nameLength;
*dst++ = ' ';
*dst++ = ' ';
*dst++ = ' ';
*dst++ = '(';
memcpy(dst, matches[i]->ident().c_str(), icaoLength);
dst += icaoLength;
*dst++ = ')';
*dst++ = 0;
result[i] = entry;
}
return result;
}
static void validateSGGeod(const SGGeod& geod)
{
if (osg::isNaN(geod.getLatitudeDeg()) ||
osg::isNaN(geod.getLongitudeDeg()))
{
throw sg_range_exception("position is invalid, NaNs");
}
}
///////////////////////////////////////////////////////////////////////////////
bool
FGPositioned::Filter::hasTypeRange() const
{
assert(minType() <= maxType());
return (minType() != INVALID) && (maxType() != INVALID);
}
bool
FGPositioned::Filter::passType(Type aTy) const
{
assert(hasTypeRange());
return (minType() <= aTy) && (maxType() >= aTy);
}
static FGPositioned::List
findAll(const NamedPositionedIndex& aIndex,
const std::string& aName,
FGPositioned::Filter* aFilter,
bool aExact)
{
FGPositioned::List result;
if (aName.empty()) {
return result;
}
std::string name = boost::to_upper_copy(aName);
NamedPositionedIndex::const_iterator upperBound;
if (aExact) {
upperBound = aIndex.upper_bound(name);
} else {
std::string upperBoundId = name;
upperBoundId[upperBoundId.size()-1]++;
upperBound = aIndex.lower_bound(upperBoundId);
}
NamedPositionedIndex::const_iterator it = aIndex.lower_bound(name);
for (; it != upperBound; ++it) {
FGPositionedRef candidate = it->second;
if (aFilter) {
if (aFilter->hasTypeRange() && !aFilter->passType(candidate->type())) {
continue;
}
if (!aFilter->pass(candidate)) {
continue;
}
}
result.push_back(candidate);
}
return result;
}
///////////////////////////////////////////////////////////////////////////////
FGPositioned::FGPositioned(Type ty, const std::string& aIdent, const SGGeod& aPos) :
mPosition(aPos),
mType(ty),
mIdent(aIdent)
{
}
void FGPositioned::init(bool aIndexed)
{
SGReferenced::get(this); // hold an owning ref, for the moment
mCart = SGVec3d::fromGeod(mPosition);
if (aIndexed) {
assert(mType != TAXIWAY && mType != PAVEMENT);
addToIndices(this);
}
}
FGPositioned::~FGPositioned()
{
//std::cout << "destroying:" << mIdent << "/" << nameForType(mType) << std::endl;
removeFromIndices(this);
}
FGPositioned*
FGPositioned::createUserWaypoint(const std::string& aIdent, const SGGeod& aPos)
{
FGPositioned* wpt = new FGPositioned(WAYPOINT, aIdent, aPos);
wpt->init(true);
return wpt;
}
const SGVec3d&
FGPositioned::cart() const
{
return mCart;
}
FGPositioned::Type FGPositioned::typeFromName(const std::string& aName)
{
if (aName.empty() || (aName == "")) {
return INVALID;
}
typedef struct {
const char* _name;
Type _ty;
} NameTypeEntry;
const NameTypeEntry names[] = {
{"airport", AIRPORT},
{"vor", VOR},
{"ndb", NDB},
{"wpt", WAYPOINT},
{"fix", FIX},
{"tacan", TACAN},
{"dme", DME},
// aliases
{"waypoint", WAYPOINT},
{"apt", AIRPORT},
{"arpt", AIRPORT},
{"any", INVALID},
{"all", INVALID},
{NULL, INVALID}
};
std::string lowerName(boost::to_lower_copy(aName));
for (const NameTypeEntry* n = names; (n->_name != NULL); ++n) {
if (::strcmp(n->_name, lowerName.c_str()) == 0) {
return n->_ty;
}
}
SG_LOG(SG_GENERAL, SG_WARN, "FGPositioned::typeFromName: couldn't match:" << aName);
return INVALID;
}
const char* FGPositioned::nameForType(Type aTy)
{
switch (aTy) {
case RUNWAY: return "runway";
case TAXIWAY: return "taxiway";
case PAVEMENT: return "pavement";
case PARK_STAND: return "parking stand";
case FIX: return "fix";
case VOR: return "VOR";
case NDB: return "NDB";
case ILS: return "ILS";
case LOC: return "localiser";
case GS: return "glideslope";
case OM: return "outer-marker";
case MM: return "middle-marker";
case IM: return "inner-marker";
case AIRPORT: return "airport";
case HELIPORT: return "heliport";
case SEAPORT: return "seaport";
case WAYPOINT: return "waypoint";
case DME: return "dme";
case TACAN: return "tacan";
default:
return "unknown";
}
}
///////////////////////////////////////////////////////////////////////////////
// search / query functions
FGPositionedRef
FGPositioned::findClosestWithIdent(const std::string& aIdent, const SGGeod& aPos, Filter* aFilter)
{
validateSGGeod(aPos);
FGPositioned::List r(findAll(global_identIndex, aIdent, aFilter, true));
if (r.empty()) {
return FGPositionedRef();
}
sortByRange(r, aPos);
return r.front();
}
FGPositioned::List
FGPositioned::findWithinRange(const SGGeod& aPos, double aRangeNm, Filter* aFilter)
{
validateSGGeod(aPos);
List result;
Octree::findAllWithinRange(SGVec3d::fromGeod(aPos),
aRangeNm * SG_NM_TO_METER, aFilter, result);
return result;
}
FGPositioned::List
FGPositioned::findAllWithIdent(const std::string& aIdent, Filter* aFilter, bool aExact)
{
return findAll(global_identIndex, aIdent, aFilter, aExact);
}
FGPositioned::List
FGPositioned::findAllWithName(const std::string& aName, Filter* aFilter, bool aExact)
{
return findAll(global_nameIndex, aName, aFilter, aExact);
}
FGPositionedRef
FGPositioned::findClosest(const SGGeod& aPos, double aCutoffNm, Filter* aFilter)
{
validateSGGeod(aPos);
List l(findClosestN(aPos, 1, aCutoffNm, aFilter));
if (l.empty()) {
return NULL;
}
assert(l.size() == 1);
return l.front();
}
FGPositioned::List
FGPositioned::findClosestN(const SGGeod& aPos, unsigned int aN, double aCutoffNm, Filter* aFilter)
{
validateSGGeod(aPos);
List result;
Octree::findNearestN(SGVec3d::fromGeod(aPos), aN, aCutoffNm * SG_NM_TO_METER, aFilter, result);
return result;
}
FGPositionedRef
FGPositioned::findNextWithPartialId(FGPositionedRef aCur, const std::string& aId, Filter* aFilter)
{
if (aId.empty()) {
return NULL;
}
std::string id(boost::to_upper_copy(aId));
// It is essential to bound our search, to avoid iterating all the way to the end of the database.
// Do this by generating a second ID with the final character incremented by 1.
// e.g., if the partial ID is "KI", we wish to search "KIxxx" but not "KJ".
std::string upperBoundId = id;
upperBoundId[upperBoundId.size()-1]++;
NamedPositionedIndex::const_iterator upperBound = global_identIndex.lower_bound(upperBoundId);
NamedIndexRange range = global_identIndex.equal_range(id);
while (range.first != upperBound) {
for (; range.first != range.second; ++range.first) {
FGPositionedRef candidate = range.first->second;
if (aCur == candidate) {
aCur = NULL; // found our start point, next match will pass
continue;
}
if (aFilter) {
if (aFilter->hasTypeRange() && !aFilter->passType(candidate->type())) {
continue;
}
if (!aFilter->pass(candidate)) {
continue;
}
}
if (!aCur) {
return candidate;
}
}
// Unable to match the filter with this range - try the next range.
range = global_identIndex.equal_range(range.second->first);
}
return NULL; // Reached the end of the valid sequence with no match.
}
void
FGPositioned::sortByRange(List& aResult, const SGGeod& aPos)
{
validateSGGeod(aPos);
SGVec3d cartPos(SGVec3d::fromGeod(aPos));
// computer ordering values
Octree::FindNearestResults r;
List::iterator it = aResult.begin(), lend = aResult.end();
for (; it != lend; ++it) {
double d2 = distSqr((*it)->cart(), cartPos);
r.push_back(Octree::OrderedPositioned(*it, d2));
}
// sort
std::sort(r.begin(), r.end());
// convert to a plain list
unsigned int count = aResult.size();
for (unsigned int i=0; i<count; ++i) {
aResult[i] = r[i].get();
}
}
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