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Diffstat (limited to 'src/third-party/intervaltree/IntervalTree.h')
| -rw-r--r-- | src/third-party/intervaltree/IntervalTree.h | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/src/third-party/intervaltree/IntervalTree.h b/src/third-party/intervaltree/IntervalTree.h new file mode 100644 index 0000000..d631b5f --- /dev/null +++ b/src/third-party/intervaltree/IntervalTree.h @@ -0,0 +1,346 @@ +/** + * Origin: https://github.com/ekg/intervaltree + */ + +#ifndef __INTERVAL_TREE_H +#define __INTERVAL_TREE_H + +#include <algorithm> +#include <cassert> +#include <iostream> +#include <limits> +#include <memory> +#include <vector> + +namespace interval_tree { + +template <class Scalar, typename Value> +class Interval { +public: + Scalar start; + Scalar stop; + Value value; + Interval(const Scalar& s, const Scalar& e, const Value& v) + : start(std::min(s, e)) + , stop(std::max(s, e)) + , value(v) + {} +}; + +template <class Scalar, typename Value> +Value intervalStart(const Interval<Scalar,Value>& i) { + return i.start; +} + +template <class Scalar, typename Value> +Value intervalStop(const Interval<Scalar, Value>& i) { + return i.stop; +} + +template <class Scalar, typename Value> +std::ostream& operator<<(std::ostream& out, const Interval<Scalar, Value>& i) { + out << "Interval(" << i.start << ", " << i.stop << "): " << i.value; + return out; +} + +template <class Scalar, class Value> +class IntervalTree { +public: + typedef Interval<Scalar, Value> interval; + typedef std::vector<interval> interval_vector; + + + struct IntervalStartCmp { + bool operator()(const interval& a, const interval& b) { + return a.start < b.start; + } + }; + + struct IntervalStopCmp { + bool operator()(const interval& a, const interval& b) { + return a.stop < b.stop; + } + }; + + IntervalTree() + : left(nullptr) + , right(nullptr) + , center(0) + {} + + ~IntervalTree() = default; + + std::unique_ptr<IntervalTree> clone() const { + return std::unique_ptr<IntervalTree>(new IntervalTree(*this)); + } + + IntervalTree(const IntervalTree& other) + : intervals(other.intervals), + left(other.left ? other.left->clone() : nullptr), + right(other.right ? other.right->clone() : nullptr), + center(other.center) + {} + + IntervalTree& operator=(IntervalTree&&) = default; + IntervalTree(IntervalTree&&) = default; + + IntervalTree& operator=(const IntervalTree& other) { + center = other.center; + intervals = other.intervals; + left = other.left ? other.left->clone() : nullptr; + right = other.right ? other.right->clone() : nullptr; + return *this; + } + + IntervalTree( + interval_vector&& ivals, + std::size_t depth = 16, + std::size_t minbucket = 64, + std::size_t maxbucket = 512, + Scalar leftextent = 0, + Scalar rightextent = 0) + : left(nullptr) + , right(nullptr) + { + --depth; + const auto minmaxStop = std::minmax_element(ivals.begin(), ivals.end(), + IntervalStopCmp()); + const auto minmaxStart = std::minmax_element(ivals.begin(), ivals.end(), + IntervalStartCmp()); + if (!ivals.empty()) { + center = (minmaxStart.first->start + minmaxStop.second->stop) / 2; + } + if (leftextent == 0 && rightextent == 0) { + // sort intervals by start + std::sort(ivals.begin(), ivals.end(), IntervalStartCmp()); + } else { + assert(std::is_sorted(ivals.begin(), ivals.end(), IntervalStartCmp())); + } + if (depth == 0 || (ivals.size() < minbucket && ivals.size() < maxbucket)) { + std::sort(ivals.begin(), ivals.end(), IntervalStartCmp()); + intervals = std::move(ivals); + assert(is_valid().first); + return; + } else { + Scalar leftp = 0; + Scalar rightp = 0; + + if (leftextent || rightextent) { + leftp = leftextent; + rightp = rightextent; + } else { + leftp = ivals.front().start; + rightp = std::max_element(ivals.begin(), ivals.end(), + IntervalStopCmp())->stop; + } + + interval_vector lefts; + interval_vector rights; + + for (typename interval_vector::const_iterator i = ivals.begin(); + i != ivals.end(); ++i) { + const interval& interval = *i; + if (interval.stop < center) { + lefts.push_back(interval); + } else if (interval.start > center) { + rights.push_back(interval); + } else { + assert(interval.start <= center); + assert(center <= interval.stop); + intervals.push_back(interval); + } + } + + if (!lefts.empty()) { + left.reset(new IntervalTree(std::move(lefts), + depth, minbucket, maxbucket, + leftp, center)); + } + if (!rights.empty()) { + right.reset(new IntervalTree(std::move(rights), + depth, minbucket, maxbucket, + center, rightp)); + } + } + assert(is_valid().first); + } + + // Call f on all intervals near the range [start, stop]: + template <class UnaryFunction> + void visit_near(const Scalar& start, const Scalar& stop, UnaryFunction f) const { + if (!intervals.empty() && ! (stop < intervals.front().start)) { + for (auto & i : intervals) { + f(i); + } + } + if (left && start <= center) { + left->visit_near(start, stop, f); + } + if (right && stop >= center) { + right->visit_near(start, stop, f); + } + } + + // Call f on all intervals crossing pos + template <class UnaryFunction> + void visit_overlapping(const Scalar& pos, UnaryFunction f) const { + visit_overlapping(pos, pos, f); + } + + // Call f on all intervals overlapping [start, stop] + template <class UnaryFunction> + void visit_overlapping(const Scalar& start, const Scalar& stop, UnaryFunction f) const { + auto filterF = [&](const interval& interval) { + if (interval.stop >= start && interval.start <= stop) { + // Only apply f if overlapping + f(interval); + } + }; + visit_near(start, stop, filterF); + } + + // Call f on all intervals contained within [start, stop] + template <class UnaryFunction> + void visit_contained(const Scalar& start, const Scalar& stop, UnaryFunction f) const { + auto filterF = [&](const interval& interval) { + if (start <= interval.start && interval.stop <= stop) { + f(interval); + } + }; + visit_near(start, stop, filterF); + } + + interval_vector findOverlapping(const Scalar& start, const Scalar& stop) const { + interval_vector result; + visit_overlapping(start, stop, + [&](const interval& interval) { + result.emplace_back(interval); + }); + return result; + } + + interval_vector findContained(const Scalar& start, const Scalar& stop) const { + interval_vector result; + visit_contained(start, stop, + [&](const interval& interval) { + result.push_back(interval); + }); + return result; + } + bool empty() const { + if (left && !left->empty()) { + return false; + } + if (!intervals.empty()) { + return false; + } + if (right && !right->empty()) { + return false; + } + return true; + } + + template <class UnaryFunction> + void visit_all(UnaryFunction f) const { + if (left) { + left->visit_all(f); + } + std::for_each(intervals.begin(), intervals.end(), f); + if (right) { + right->visit_all(f); + } + } + + std::pair<Scalar, Scalar> extentBruitForce() const { + struct Extent { + std::pair<Scalar, Scalar> x = {std::numeric_limits<Scalar>::max(), + std::numeric_limits<Scalar>::min() }; + void operator()(const interval & interval) { + x.first = std::min(x.first, interval.start); + x.second = std::max(x.second, interval.stop); + } + }; + Extent extent; + + visit_all([&](const interval & interval) { extent(interval); }); + return extent.x; + } + + // Check all constraints. + // If first is false, second is invalid. + std::pair<bool, std::pair<Scalar, Scalar>> is_valid() const { + const auto minmaxStop = std::minmax_element(intervals.begin(), intervals.end(), + IntervalStopCmp()); + const auto minmaxStart = std::minmax_element(intervals.begin(), intervals.end(), + IntervalStartCmp()); + + std::pair<bool, std::pair<Scalar, Scalar>> result = {true, { std::numeric_limits<Scalar>::max(), + std::numeric_limits<Scalar>::min() }}; + if (!intervals.empty()) { + result.second.first = std::min(result.second.first, minmaxStart.first->start); + result.second.second = std::min(result.second.second, minmaxStop.second->stop); + } + if (left) { + auto valid = left->is_valid(); + result.first &= valid.first; + result.second.first = std::min(result.second.first, valid.second.first); + result.second.second = std::min(result.second.second, valid.second.second); + if (!result.first) { return result; } + if (valid.second.second >= center) { + result.first = false; + return result; + } + } + if (right) { + auto valid = right->is_valid(); + result.first &= valid.first; + result.second.first = std::min(result.second.first, valid.second.first); + result.second.second = std::min(result.second.second, valid.second.second); + if (!result.first) { return result; } + if (valid.second.first <= center) { + result.first = false; + return result; + } + } + if (!std::is_sorted(intervals.begin(), intervals.end(), IntervalStartCmp())) { + result.first = false; + } + return result; + } + + friend std::ostream& operator<<(std::ostream& os, const IntervalTree& itree) { + return writeOut(os, itree); + } + + friend std::ostream& writeOut(std::ostream& os, const IntervalTree& itree, + std::size_t depth = 0) { + auto pad = [&]() { for (std::size_t i = 0; i != depth; ++i) { os << ' '; } }; + pad(); os << "center: " << itree.center << '\n'; + for (const interval & inter : itree.intervals) { + pad(); os << inter << '\n'; + } + if (itree.left) { + pad(); os << "left:\n"; + writeOut(os, *itree.left, depth + 1); + } else { + pad(); os << "left: nullptr\n"; + } + if (itree.right) { + pad(); os << "right:\n"; + writeOut(os, *itree.right, depth + 1); + } else { + pad(); os << "right: nullptr\n"; + } + return os; + } + +private: + interval_vector intervals; + std::unique_ptr<IntervalTree> left; + std::unique_ptr<IntervalTree> right; + Scalar center; +}; + +} + +#endif |