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0df1056dd4
A very fast static spatial index for 2D points based on a flat KD-tree, using https://github.com/mourner/kdbush.hpp Compared to QgsSpatialIndex, this index: - supports single point features only (no multipoints) - is static (features cannot be added or removed from the index after construction) - is much faster! - supports true "distance based" searches, i.e. return all points within a radius from a search point
34 lines
842 B
C++
34 lines
842 B
C++
#include "include/kdbush.hpp"
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#include <chrono>
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#include <iostream>
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#include <random>
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#include <vector>
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int main() {
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std::mt19937 gen(0);
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std::uniform_int_distribution<> dis(-10000, 10000);
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using Point = std::pair<int, int>;
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const std::size_t num_points = 1000000;
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std::vector<Point> points;
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points.reserve(num_points);
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for (std::size_t i = 0; i < num_points; i++) {
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points.emplace_back(dis(gen), dis(gen));
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}
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const auto started = std::chrono::high_resolution_clock::now();
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kdbush::KDBush<Point> index(points);
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const auto finished = std::chrono::high_resolution_clock::now();
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const auto duration =
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std::chrono::duration_cast<std::chrono::nanoseconds>(finished - started).count();
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std::cerr << "indexed 1M points in " << (duration / 1e6) << "ms\n";
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return 0;
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}
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