/*
Copyright 2008 Intel Corporation
Use, modification and distribution are subject to the Boost Software License,
Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt).
*/
#ifndef BOOST_POLYGON_BOOLEAN_OP_HPP
#define BOOST_POLYGON_BOOLEAN_OP_HPP
namespace boost { namespace polygon{
namespace boolean_op {
//BooleanOp is the generic boolean operation scanline algorithm that provides
//all the simple boolean set operations on manhattan data. By templatizing
//the intersection count of the input and algorithm internals it is extensible
//to multi-layer scans, properties and other advanced scanline operations above
//and beyond simple booleans.
//T must cast to int
template <class T, typename Unit>
class BooleanOp {
public:
typedef std::map<Unit, T> ScanData;
typedef std::pair<Unit, T> ElementType;
protected:
ScanData scanData_;
typename ScanData::iterator nextItr_;
T nullT_;
public:
inline BooleanOp () : scanData_(), nextItr_(), nullT_() { nextItr_ = scanData_.end(); nullT_ = 0; }
inline BooleanOp (T nullT) : scanData_(), nextItr_(), nullT_(nullT) { nextItr_ = scanData_.end(); }
inline BooleanOp (const BooleanOp& that) : scanData_(that.scanData_), nextItr_(),
nullT_(that.nullT_) { nextItr_ = scanData_.begin(); }
inline BooleanOp& operator=(const BooleanOp& that);
//moves scanline forward
inline void advanceScan() { nextItr_ = scanData_.begin(); }
//proceses the given interval and T data
//appends output edges to cT
template <class cT>
inline void processInterval(cT& outputContainer, interval_data<Unit> ivl, T deltaCount);
private:
inline typename ScanData::iterator lookup_(Unit pos){
if(nextItr_ != scanData_.end() && nextItr_->first >= pos) {
return nextItr_;
}
return nextItr_ = scanData_.lower_bound(pos);
}
inline typename ScanData::iterator insert_(Unit pos, T count){
return nextItr_ = scanData_.insert(nextItr_, ElementType(pos, count));
}
template <class cT>
inline void evaluateInterval_(cT& outputContainer, interval_data<Unit> ivl, T beforeCount, T afterCount);
};
class BinaryAnd {
public:
inline BinaryAnd() {}
inline bool operator()(int a, int b) { return (a > 0) & (b > 0); }
};
class BinaryOr {
public:
inline BinaryOr() {}
inline bool operator()(int a, int b) { return (a > 0) | (b > 0); }
};
class BinaryNot {
public:
inline BinaryNot() {}
inline bool operator()(int a, int b) { return (a > 0) & !(b > 0); }
};
class BinaryXor {
public:
inline BinaryXor() {}
inline bool operator()(int a, int b) { return (a > 0) ^ (b > 0); }
};
//BinaryCount is an array of two deltaCounts coming from two different layers
//of scan event data. It is the merged count of the two suitable for consumption
//as the template argument of the BooleanOp algorithm because BinaryCount casts to int.
//T is a binary functor object that evaluates the array of counts and returns a logical
//result of some operation on those values.
//BinaryCount supports many of the operators that work with int, particularly the
//binary operators, but cannot support less than or increment.
template <class T>
class BinaryCount {
public:
inline BinaryCount()
#ifndef BOOST_POLYGON_MSVC
: counts_()
#endif
{ counts_[0] = counts_[1] = 0; }
// constructs from two integers
inline BinaryCount(int countL, int countR)
#ifndef BOOST_POLYGON_MSVC
: counts_()
#endif
{ counts_[0] = countL, counts_[1] = countR; }
inline BinaryCount& operator=(int count) { counts_[0] = count, counts_[1] = count; return *this; }
inline BinaryCount& operator=(const BinaryCount& that);
inline BinaryCount(const BinaryCount& that)
#ifndef BOOST_POLYGON_MSVC
: counts_()
#endif
{ *this = that; }
inline bool operator==(const BinaryCount& that) const;
inline bool operator!=(const BinaryCount& that) const { return !((*this) == that);}
inline BinaryCount& operator+=(const BinaryCount& that);
inline BinaryCount& operator-=(const BinaryCount& that);
inline BinaryCount operator+(const BinaryCount& that) const;
inline BinaryCount operator-(const BinaryCount& that) const;
inline BinaryCount operator-() const;
inline int& operator[](bool index) { return counts_[index]; }
//cast to int operator evaluates data using T binary functor
inline operator int() const { return T()(counts_[0], counts_[1]); }
private:
int counts_[2];
};
class UnaryCount {
public:
inline UnaryCount() : count_(0) {}
// constructs from two integers
inline explicit UnaryCount(int count) : count_(count) {}
inline UnaryCount& operator=(int count) { count_ = count; return *this; }
inline UnaryCount& operator=(const UnaryCount& that) { count_ = that.count_; return *this; }
inline UnaryCount(const UnaryCount& that) : count_(that.count_) {}
inline bool operator==(const UnaryCount& that) const { return count_ == that.count_; }
inline bool operator!=(const UnaryCount& that) const { return !((*this) == that);}
inline UnaryCount& operator+=(const UnaryCount& that) { count_ += that.count_; return *this; }
inline UnaryCount& operator-=(const UnaryCount& that) { count_ -= that.count_; return *this; }
inline UnaryCount operator+(const UnaryCount& that) const { UnaryCount tmp(*this); tmp += that; return tmp; }
inline UnaryCount operator-(const UnaryCount& that) const { UnaryCount tmp(*this); tmp -= that; return tmp; }
inline UnaryCount operator-() const { UnaryCount tmp; return tmp - *this; }
//cast to int operator evaluates data using T binary functor
inline operator int() const { return count_ % 2; }
private:
int count_;
};
template <class T, typename Unit>
inline BooleanOp<T, Unit>& BooleanOp<T, Unit>::operator=(const BooleanOp& that) {
scanData_ = that.scanData_;
nextItr_ = scanData_.begin();
nullT_ = that.nullT_;
return *this;
}
//appends output edges to cT
template <class T, typename Unit>
template <class cT>
inline void BooleanOp<T, Unit>::processInterval(cT& outputContainer, interval_data<Unit> ivl, T deltaCount) {
typename ScanData::iterator lowItr = lookup_(ivl.low());
typename ScanData::iterator highItr = lookup_(ivl.high());
//add interval to scan data if it is past the end
if(lowItr == scanData_.end()) {
lowItr = insert_(ivl.low(), deltaCount);
highItr = insert_(ivl.high(), nullT_);
evaluateInterval_(outputContainer, ivl, nullT_, deltaCount);
return;
}
//ensure that highItr points to the end of the ivl
if(highItr == scanData_.end() || (*highItr).first > ivl.high()) {
T value = nullT_;
if(highItr != scanData_.begin()) {
--highItr;
value = highItr->second;
}
nextItr_ = highItr;
highItr = insert_(ivl.high(), value);
}
//split the low interval if needed
if(lowItr->first > ivl.low()) {
if(lowItr != scanData_.begin()) {
--lowItr;
nextItr_ = lowItr;
lowItr = insert_(ivl.low(), lowItr->second);
} else {
nextItr_ = lowItr;
lowItr = insert_(ivl.low(), nullT_);
}
}
//process scan data intersecting interval
for(typename ScanData::iterator itr = lowItr; itr != highItr; ){
T beforeCount = itr->second;
T afterCount = itr->second += deltaCount;
Unit low = itr->first;
++itr;
Unit high = itr->first;
evaluateInterval_(outputContainer, interval_data<Unit>(low, high), beforeCount, afterCount);
}
//merge the bottom interval with the one below if they have the same count
if(lowItr != scanData_.begin()){
typename ScanData::iterator belowLowItr = lowItr;
--belowLowItr;
if(belowLowItr->second == lowItr->second) {
scanData_.erase(lowItr);
}
}
//merge the top interval with the one above if they have the same count
if(highItr != scanData_.begin()) {
typename ScanData::iterator beforeHighItr = highItr;
--beforeHighItr;
if(beforeHighItr->second == highItr->second) {
scanData_.erase(highItr);
highItr = beforeHighItr;
++highItr;
}
}
nextItr_ = highItr;
}
template <class T, typename Unit>
template <class cT>
inline void BooleanOp<T, Unit>::evaluateInterval_(cT& outputContainer, interval_data<Unit> ivl,
T beforeCount, T afterCount) {
bool before = (int)beforeCount > 0;
bool after = (int)afterCount > 0;
int value = (!before & after) - (before & !after);
if(value) {
outputContainer.insert(outputContainer.end(), std::pair<interval_data<Unit>, int>(ivl, value));
}
}
template <class T>
inline BinaryCount<T>& BinaryCount<T>::operator=(const BinaryCount<T>& that) {
counts_[0] = that.counts_[0];
counts_[1] = that.counts_[1];
return *this;
}
template <class T>
inline bool BinaryCount<T>::operator==(const BinaryCount<T>& that) const {
return counts_[0] == that.counts_[0] &&
counts_[1] == that.counts_[1];
}
template <class T>
inline BinaryCount<T>& BinaryCount<T>::operator+=(const BinaryCount<T>& that) {
counts_[0] += that.counts_[0];
counts_[1] += that.counts_[1];
return *this;
}
template <class T>
inline BinaryCount<T>& BinaryCount<T>::operator-=(const BinaryCount<T>& that) {
counts_[0] += that.counts_[0];
counts_[1] += that.counts_[1];
return *this;
}
template <class T>
inline BinaryCount<T> BinaryCount<T>::operator+(const BinaryCount<T>& that) const {
BinaryCount retVal(*this);
retVal += that;
return retVal;
}
template <class T>
inline BinaryCount<T> BinaryCount<T>::operator-(const BinaryCount<T>& that) const {
BinaryCount retVal(*this);
retVal -= that;
return retVal;
}
template <class T>
inline BinaryCount<T> BinaryCount<T>::operator-() const {
return BinaryCount<T>() - *this;
}
template <class T, typename Unit, typename iterator_type_1, typename iterator_type_2>
inline void applyBooleanBinaryOp(std::vector<std::pair<Unit, std::pair<Unit, int> > >& output,
//const std::vector<std::pair<Unit, std::pair<Unit, int> > >& input1,
//const std::vector<std::pair<Unit, std::pair<Unit, int> > >& input2,
iterator_type_1 itr1, iterator_type_1 itr1_end,
iterator_type_2 itr2, iterator_type_2 itr2_end,
T defaultCount) {
BooleanOp<T, Unit> boolean(defaultCount);
//typename std::vector<std::pair<Unit, std::pair<Unit, int> > >::const_iterator itr1 = input1.begin();
//typename std::vector<std::pair<Unit, std::pair<Unit, int> > >::const_iterator itr2 = input2.begin();
std::vector<std::pair<interval_data<Unit>, int> > container;
//output.reserve((std::max)(input1.size(), input2.size()));
//consider eliminating dependecy on limits with bool flag for initial state
Unit UnitMax = (std::numeric_limits<Unit>::max)();
Unit prevCoord = UnitMax;
Unit prevPosition = UnitMax;
T count(defaultCount);
//define the starting point
if(itr1 != itr1_end) {
prevCoord = (*itr1).first;
prevPosition = (*itr1).second.first;
count[0] += (*itr1).second.second;
}
if(itr2 != itr2_end) {
if((*itr2).first < prevCoord ||
((*itr2).first == prevCoord && (*itr2).second.first < prevPosition)) {
prevCoord = (*itr2).first;
prevPosition = (*itr2).second.first;
count = defaultCount;
count[1] += (*itr2).second.second;
++itr2;
} else if((*itr2).first == prevCoord && (*itr2).second.first == prevPosition) {
count[1] += (*itr2).second.second;
++itr2;
if(itr1 != itr1_end) ++itr1;
} else {
if(itr1 != itr1_end) ++itr1;
}
} else {
if(itr1 != itr1_end) ++itr1;
}
while(itr1 != itr1_end || itr2 != itr2_end) {
Unit curCoord = UnitMax;
Unit curPosition = UnitMax;
T curCount(defaultCount);
if(itr1 != itr1_end) {
curCoord = (*itr1).first;
curPosition = (*itr1).second.first;
curCount[0] += (*itr1).second.second;
}
if(itr2 != itr2_end) {
if((*itr2).first < curCoord ||
((*itr2).first == curCoord && (*itr2).second.first < curPosition)) {
curCoord = (*itr2).first;
curPosition = (*itr2).second.first;
curCount = defaultCount;
curCount[1] += (*itr2).second.second;
++itr2;
} else if((*itr2).first == curCoord && (*itr2).second.first == curPosition) {
curCount[1] += (*itr2).second.second;
++itr2;
if(itr1 != itr1_end) ++itr1;
} else {
if(itr1 != itr1_end) ++itr1;
}
} else {
++itr1;
}
if(prevCoord != curCoord) {
boolean.advanceScan();
prevCoord = curCoord;
prevPosition = curPosition;
count = curCount;
continue;
}
if(curPosition != prevPosition && count != defaultCount) {
interval_data<Unit> ivl(prevPosition, curPosition);
container.clear();
boolean.processInterval(container, ivl, count);
for(std::size_t i = 0; i < container.size(); ++i) {
std::pair<interval_data<Unit>, int>& element = container[i];
if(!output.empty() && output.back().first == prevCoord &&
output.back().second.first == element.first.low() &&
output.back().second.second == element.second * -1) {
output.pop_back();
} else {
output.push_back(std::pair<Unit, std::pair<Unit, int> >(prevCoord, std::pair<Unit, int>(element.first.low(),
element.second)));
}
output.push_back(std::pair<Unit, std::pair<Unit, int> >(prevCoord, std::pair<Unit, int>(element.first.high(),
element.second * -1)));
}
}
prevPosition = curPosition;
count += curCount;
}
}
template <class T, typename Unit>
inline void applyBooleanBinaryOp(std::vector<std::pair<Unit, std::pair<Unit, int> > >& inputOutput,
const std::vector<std::pair<Unit, std::pair<Unit, int> > >& input2,
T defaultCount) {
std::vector<std::pair<Unit, std::pair<Unit, int> > > output;
applyBooleanBinaryOp(output, inputOutput, input2, defaultCount);
if(output.size() < inputOutput.size() / 2) {
inputOutput = std::vector<std::pair<Unit, std::pair<Unit, int> > >();
} else {
inputOutput.clear();
}
inputOutput.insert(inputOutput.end(), output.begin(), output.end());
}
template <typename count_type = int>
struct default_arg_workaround {
template <typename Unit>
static inline void applyBooleanOr(std::vector<std::pair<Unit, std::pair<Unit, int> > >& input) {
BooleanOp<count_type, Unit> booleanOr;
std::vector<std::pair<interval_data<Unit>, int> > container;
std::vector<std::pair<Unit, std::pair<Unit, int> > > output;
output.reserve(input.size());
//consider eliminating dependecy on limits with bool flag for initial state
Unit UnitMax = (std::numeric_limits<Unit>::max)();
Unit prevPos = UnitMax;
Unit prevY = UnitMax;
int count = 0;
for(typename std::vector<std::pair<Unit, std::pair<Unit, int> > >::iterator itr = input.begin();
itr != input.end(); ++itr) {
Unit pos = (*itr).first;
Unit y = (*itr).second.first;
if(pos != prevPos) {
booleanOr.advanceScan();
prevPos = pos;
prevY = y;
count = (*itr).second.second;
continue;
}
if(y != prevY && count != 0) {
interval_data<Unit> ivl(prevY, y);
container.clear();
booleanOr.processInterval(container, ivl, count_type(count));
for(std::size_t i = 0; i < container.size(); ++i) {
std::pair<interval_data<Unit>, int>& element = container[i];
if(!output.empty() && output.back().first == prevPos &&
output.back().second.first == element.first.low() &&
output.back().second.second == element.second * -1) {
output.pop_back();
} else {
output.push_back(std::pair<Unit, std::pair<Unit, int> >(prevPos, std::pair<Unit, int>(element.first.low(),
element.second)));
}
output.push_back(std::pair<Unit, std::pair<Unit, int> >(prevPos, std::pair<Unit, int>(element.first.high(),
element.second * -1)));
}
}
prevY = y;
count += (*itr).second.second;
}
if(output.size() < input.size() / 2) {
input = std::vector<std::pair<Unit, std::pair<Unit, int> > >();
} else {
input.clear();
}
input.insert(input.end(), output.begin(), output.end());
}
};
}
}
}
#endif