kev/Drawer/Module/GeoSigmaDraw/SpatialIndex.h

#pragma once

#include "DrawOperator/One.h"
#include "DrawOperator/Xy.h"
#include "DrawOperator/RTree.h"

class CSpatialIndex
{
public:
	CSpatialIndex(CXy& xy)
		: m_xy(xy)
	{
		BuildRTree(xy);
	}

	/**
	 * <EFBFBD><EFBFBD>ȡ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	 *
	 * \param searchCenter	<EFBFBD><EFBFBD>ǰ<EFBFBD><EFBFBD>
	 * \param searchRadius	<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>뾶<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD>Ǿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	 * \return				<EFBFBD><EFBFBD>Χ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ԫ<EFBFBD>صĵ<EFBFBD>
	 */
	std::optional<NBase::CPoint2D> GetSnapPoint(const NBase::CPoint2D& searchCenter, double searchRadius) const
	{
		std::vector<POSITION> positions = FindElementsInRadius(searchCenter, searchRadius);
		return positions.empty() ? std::nullopt : FindNearestPoint(positions, searchCenter);
	}

	/**
	 * <EFBFBD><EFBFBD><EFBFBD>ҷ<EFBFBD>Χ<EFBFBD><EFBFBD>Ԫ<EFBFBD><EFBFBD>
	 * 
	 * \param rect	<EFBFBD><EFBFBD>Χ
	 * \return		<EFBFBD><EFBFBD><EFBFBD>ط<EFBFBD>Χ<EFBFBD><EFBFBD>Ԫ<EFBFBD><EFBFBD><EFBFBD>б<EFBFBD>
	 */
	std::vector<POSITION> FindElementsInRect(const NBase::CRect8& rect) const
	{	
		double minValue[2]{ rect.left, rect.top };
		double maxValue[2]{ rect.right, rect.bottom };

		std::vector<POSITION> positions;

		auto callback = [&positions](POSITION pos)
			{
				positions.push_back(pos);
				return true;
			};

		m_tree.Search(minValue, maxValue, callback);

		return positions;

	}

	/**
	 * <EFBFBD><EFBFBD><EFBFBD>ҷ<EFBFBD>Χ<EFBFBD>ڵ<EFBFBD>ͼԪ
	 * 
	 * \param searchCenter	<EFBFBD><EFBFBD>ǰ<EFBFBD><EFBFBD>
	 * \param searchRadius	<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>뾶<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD>Ǿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	 * \return 
	 */
	std::vector<POSITION> FindElementsInRadius(const NBase::CPoint2D& searchCenter, double searchRadius) const
	{
		NBase::CRect8 rect(
			searchCenter.x0 - searchRadius / 2,
			searchCenter.y0 - searchRadius / 2,
			searchCenter.x0 + searchRadius / 2,
			searchCenter.y0 + searchRadius / 2
		);
		return FindElementsInRect(rect);
	}

private:
	/**
	 * <EFBFBD><EFBFBD><EFBFBD><EFBFBD> RTree
	 * 
	 */
	void BuildRTree(CXy& xy)
	{
		CPtrList& values = *(xy.GetValueList());

		for (POSITION pos = values.GetHeadPosition(); pos != nullptr; values.GetNext(pos))
		{
			COne* pOne = reinterpret_cast<COne*>(values.GetAt(pos));
			if (IsVisiblePointElement(pOne))
			{
				NBase::CRect8 range(1e100, -1e100, -1e100, 1e100);
				pOne->GetRange(range);

				double minX = min(range.left, range.right);
				double minY = min(range.top, range.bottom);
				double maxX = max(range.left, range.right);
				double maxY = max(range.top, range.bottom);

				double minValue[2]{ minX, minY };
				double maxValue[2]{ maxX, maxY };

				m_tree.Insert(minValue, maxValue, pos);
			}
		}

	}

	/**
	 * <EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ԫ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͼԪ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	 * 
	 * \param positions		ͼԪ POSITION
	 * \param searchCenter	<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>㣬<EFBFBD><EFBFBD>ʵ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
	 * \return				<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD><EFBFBD><EFBFBD>꣬<EFBFBD><EFBFBD><EFBFBD>򷵻<EFBFBD> std::nullopt;
	 */
	std::optional<NBase::CPoint2D> FindNearestPoint(const std::vector<POSITION>& positions, const NBase::CPoint2D& searchCenter) const
	{
#pragma push_macro("max")
#undef max

		double minDistanceSquared = std::numeric_limits<double>::max();
		NBase::CPoint2D nearestPoint; // <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĵ<EFBFBD>

		// <20>ӷ<EFBFBD>Χ<EFBFBD>ڲ<EFBFBD><DAB2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ĵ<EFBFBD>
		for (POSITION pos : positions)
		{
			COne* pOne = m_xy.GetAt(pos);
			if (!IsVisiblePointElement(pOne))
			{
				continue;
			}

			CPointNameEx* pPoint = pOne->GetValueSafe<CPointNameEx>();
			if (pPoint == nullptr)
			{
				continue;
			}

			double dx = pPoint->x0 - searchCenter.x0;
			double dy = pPoint->y0 - searchCenter.y0;
			// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵֻ<CAB5><D6BB>֪<EFBFBD><D6AA><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Զ<EFBFBD><D4B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʵ<EFBFBD><CAB5><EFBFBD>룬<EFBFBD><EBA3AC><EFBFBD>Բ<EFBFBD><D4B2>ﲻ<EFBFBD><EFB2BB><EFBFBD><EFBFBD><EFBFBD>ˣ<EFBFBD><CBA3><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ܿ<EFBFBD><DCBF><EFBFBD>
			double distanceSquared = dx * dx + dy * dy;

			if (distanceSquared < minDistanceSquared)
			{
				minDistanceSquared = distanceSquared;
				nearestPoint = NBase::CPoint2D(pPoint->x0, pPoint->y0);
			}
		}
		return (minDistanceSquared != std::numeric_limits<double>::max())
			? std::optional(nearestPoint)
			: std::nullopt;

#pragma pop_macro("max")
	}

	bool IsVisiblePointElement(COne* pOne) const
	{
		return pOne != nullptr
			&& pOne->GetType() == DOUBLEFOX_POINT
			&& pOne->IsView();
	}

	RTree<POSITION, double, 2> m_tree;
	CXy& m_xy;
};