boost库之geometry<二>

#include <boost/assign.hpp>
#include <boost/geometry/core/point_type.hpp>
#include <boost/geometry/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/linestring.hpp>
#include <boost/geometry/geometries/box.hpp>
#include <boost/geometry/geometries/ring.hpp>
#include <boost/geometry/geometries/polygon.hpp>

#include <boost/geometry/algorithms/transform.hpp>
#include <boost/geometry/strategies/transform/inverse_transformer.hpp>
#include <boost/geometry/strategies/transform/matrix_transformers.hpp>

namespace bg = boost::geometry;
typedef bg::model::d2::point_xy<double> DPoint;
typedef bg::model::segment<DPoint> DSegment;
typedef bg::model::linestring<DPoint> DLineString;
typedef bg::model::box<DPoint> DBox;
typedef bg::model::ring<DPoint, false> DRing;
typedef bg::model::polygon<DPoint, false> DPolygon;
//对Geometry库一些函数进行了封装，更加方便使用，包括(平移，旋转，缩放，求点到直线的垂足，通过比例求段上的点等等)
namespace GeometryExtend
{
	DPoint operator +(const DPoint& pt1, const DPoint& pt2)
	{
		DPoint pt(pt1);
		bg::add_point(pt, pt2);
		return pt;
	}

	const DPoint& operator +=(DPoint& pt1, const DPoint& pt2)
	{
		bg::add_point(pt1, pt2);
		return pt1;
	}

	DPoint operator -(const DPoint& pt1, const DPoint& pt2)
	{
		DPoint pt(pt1);
		bg::subtract_point(pt, pt2);
		return pt;
	}

	const DPoint& operator -=(DPoint& pt1, const DPoint& pt2)
	{
		bg::subtract_point(pt1, pt2);
		return pt1;
	}

	//
	//	平移变换
	//
	template<typename Geometry, typename CalculationType>
	struct translate_impl
	{
		static void apply(Geometry& geometry, const CalculationType& x, const CalculationType& y)
		{
			bg::strategy::transform::translate_transformer<CalculationType, 2, 2> t(x, y);
			bg::transform(geometry, geometry, t);
		}
	};

	template<typename Geometry, typename CalculationType>
	struct translate_trais
	{
		static void apply(Geometry& geometry, const CalculationType& x, const CalculationType& y);
	};


#define TRANSLATE_TRAIS(Geometry) \
	template<typename CalculationType> \
	struct translate_trais<Geometry, CalculationType> \
	{ \
		static void apply(Geometry& geometry, const CalculationType& x, const CalculationType& y) \
		{ \
			translate_impl<Geometry, CalculationType>::apply(geometry, x, y); \
		} \
	};

	TRANSLATE_TRAIS(DPoint)
	TRANSLATE_TRAIS(DSegment)
	TRANSLATE_TRAIS(DBox)
	TRANSLATE_TRAIS(DRing)
	TRANSLATE_TRAIS(DPolygon)

	template<typename Geometry, typename CalculationType>
	void translate(Geometry& geometry, const CalculationType& x, const CalculationType& y)
	{
		translate_trais<Geometry, CalculationType>::apply(geometry, x, y);
	}


	//
	//	旋转变换
	//
	template<typename Geometry, typename DegreeOrRadian, typename CalculationType>
	struct rotate_impl
	{
		static void apply(Geometry& geometry, const CalculationType& angle)
		{
			bg::strategy::transform::rotate_transformer<DegreeOrRadian, CalculationType, 2, 2> t(angle);
			bg::transform(geometry, geometry, t);
		}
	};

	template<typename Geometry, typename DegreeOrRadian, typename CalculationType>
	struct rotate_trais
	{
		static void apply(Geometry& geometry, const CalculationType& angle);
	};

#define ROTATE_TRAIS(Geometry, DegreeOrRadian) \
	template<typename CalculationType> \
	struct rotate_trais<Geometry, DegreeOrRadian, CalculationType> \
	{ \
		static void apply(Geometry& geometry, const CalculationType& angle) \
		{ \
			rotate_impl<Geometry, DegreeOrRadian, CalculationType>::apply(geometry, angle); \
		} \
	};

	ROTATE_TRAIS(DPoint, bg::degree)
		ROTATE_TRAIS(DPoint, bg::radian)
		ROTATE_TRAIS(DSegment, bg::degree)
		ROTATE_TRAIS(DSegment, bg::radian)
		ROTATE_TRAIS(DBox, bg::degree)
		ROTATE_TRAIS(DBox, bg::radian)
		ROTATE_TRAIS(DRing, bg::degree)
		ROTATE_TRAIS(DRing, bg::radian)
		ROTATE_TRAIS(DPolygon, bg::degree)
		ROTATE_TRAIS(DPolygon, bg::radian)

	template<typename Geometry, typename DegreeOrRadian, typename CalculationType>
	void rotate(Geometry& geometry, const DegreeOrRadian&, const CalculationType& angle)
	{
		rotate_trais<Geometry, DegreeOrRadian, CalculationType>::apply(geometry, angle);
	}

	template<typename Geometry, typename Point, typename DegreeOrRadian, typename CalculationType>
	void point_rotate(Geometry& geometry, const Point& point, const DegreeOrRadian& type, const CalculationType& angle)
	{
		Point pt(0, 0);

		bg::subtract_point(pt, point);
		translate(geometry, bg::get<0>(pt), bg::get<1>(pt));
		rotate(geometry, type, angle);
		translate(geometry, bg::get<0>(point), bg::get<1>(point));
	}
	

	//
	//	比例变形
	//
	template<typename Geometry, typename CalculationType>
	struct scale_impl
	{
		static void apply(Geometry& geometry, const CalculationType& scale_x, const CalculationType& scale_y)
		{
			bg::strategy::transform::scale_transformer<CalculationType, 2, 2> t(scale_x, scale_y);
			bg::transform(geometry, geometry, t);
		}
	};

	template<typename Geometry, typename CalculationType>
	struct scale_trais
	{
		static void apply(Geometry& geometry, const CalculationType& scale_x, const CalculationType& scale_y);
	};

#define SCALE_TRAIS(Geometry) \
	template<typename CalculationType> \
	struct scale_trais<Geometry, CalculationType> \
	{ \
		static void apply(Geometry& geometry, const CalculationType& scale_x, const CalculationType& scale_y) \
		{ \
			scale_impl<Geometry, CalculationType>::apply(geometry, scale_x, scale_y); \
		} \
	};

	SCALE_TRAIS(DPoint)
	SCALE_TRAIS(DSegment)
	SCALE_TRAIS(DBox)
	SCALE_TRAIS(DRing)
	SCALE_TRAIS(DPolygon)

	template<typename Geometry, typename CalculationType>
	void scale(Geometry& geometry, const CalculationType& scale_x, const CalculationType& scale_y)
	{
		scale_trais<Geometry, CalculationType>::apply(geometry, scale_x, scale_y);
	}


	//
	//	函数功能：
	//		扩充box
	//
	template<typename Geometry, typename CalculateType>
	void InflateBox(Geometry& geometry, CalculateType const& cx, CalculateType const& cy)
	{
		typedef typename bg::point_type<Geometry>::type point_type;
		point_type& ptMin = geometry.min_corner();
		point_type& ptMax = geometry.max_corner();

		ptMin.x(ptMin.x() - cx);
		ptMin.y(ptMin.y() - cy);
		ptMax.x(ptMax.x() + cx);
		ptMax.y(ptMax.y() + cy);
	}

	//
	//	函数功能：
	//		求点到线段的垂足；
	//	返回值：	
	//		true，垂足在线段上；
	//		false，垂足在线段外；
	//
	template<typename Point, typename Segment>
	bool point_to_segment_org(Point const& point, Segment const& segment, Point& ptOut)
	{
		bool bInSegment = true;

		try
		{
			typedef typename bg::point_type<Segment>::type point_type;
			point_type p[2] = {segment.first, segment.second};

			if (boost::geometry::equals(point, p[0]) ||
				boost::geometry::equals(point, p[1]))
			{
				boost::geometry::assign_point(ptOut, point);
				bInSegment = true;
				throw bInSegment;
			}

			point_type v(p[1]), w(point);

			boost::geometry::subtract_point(v, p[0]);
			boost::geometry::subtract_point(w, p[0]);

			typedef typename bg::select_calculation_type<Point, Segment, void>::type calculation_type;

			calculation_type const zero = calculation_type();
			calculation_type const c1 = boost::geometry::dot_product(w, v);
			if (c1 < zero)
			{
				bInSegment = false;
			}

			double const c2 = boost::geometry::dot_product(v, v);
			if (c2 < c1)
			{
				bInSegment = false;
			}

			calculation_type const b = c1 / c2;
			DPoint projected(p[0]);

			boost::geometry::multiply_value(v, b);
			boost::geometry::add_point(projected, v);
			boost::geometry::assign_point(ptOut, projected);
		}
		catch (bool)
		{
		}

		return bInSegment;
	}


	//
	//	函数功能：
	//		通过比例求段上的点；
	//
	template<typename Segment, typename Point>
	void get_segment_on_point_by_scale(Segment const& segment, double const& dScale, Point& ptOut)
	{
		typedef typename bg::point_type<Segment>::type point_type;

		point_type p[2] = {segment.first, segment.second};
		point_type v(p[1]);
		point_type ptDest(p[0]);
		
		boost::geometry::subtract_point(v, p[0]);
		boost::geometry::multiply_value(v, dScale);
		boost::geometry::add_point(ptDest, v);
		boost::geometry::assign_point(ptOut, ptDest);
	}


	//
	//	函数功能：
	//		通过长度求段上的点；
	//
	template<typename Segment, typename Point>
	void get_segment_on_point_by_length(Segment const& segment, double const& dLength, Point& ptOut)
	{
		typedef typename bg::point_type<Segment>::type point_type;

		point_type p[2] = {segment.first, segment.second};
		double dTotalLength = boost::geometry::distance(p[0], p[1]);
		double dScale = dLength / dTotalLength;

		get_segment_on_point_by_scale(segment, dScale, ptOut);
	}
}
 
 
int main()
{
	DBox box1(DPoint(100, 100), DPoint(300, 200));
	GeometryExtend::InflateBox(box1, 20, 10);

	DSegment sg1(DPoint(100, 100), DPoint(300, 300));
	DPoint pt1(300, 100);
	DPoint pt2(100, 0);
	DPoint ptOut;
	bool bOnSegment;

	bOnSegment = GeometryExtend::point_to_segment_org(pt1, sg1, ptOut);
	bOnSegment = GeometryExtend::point_to_segment_org(pt2, sg1, ptOut);

	GeometryExtend::get_segment_on_point_by_scale(sg1, 0.5, ptOut);
	GeometryExtend::get_segment_on_point_by_length(sg1, 0, ptOut);

	DPoint pt4;
	DSegment sg4;
	//平移变换
	bg::assign_point(pt4, pt1);
	GeometryExtend::translate(pt4, 10, 20);
	bg::assign(sg4, sg1);
	GeometryExtend::translate(sg4, 10, 20);

	//旋转变形
	bg::assign(pt4, pt1);
	GeometryExtend::rotate(pt4, bg::degree(), 45.0);
	bg::assign(sg4, sg1);
	GeometryExtend::rotate(sg4, bg::degree(), 45.0);

	//比例变换
	bg::assign(pt4, pt1);
	GeometryExtend::scale(pt4, 0.5, 0.2);
	bg::assign(sg4, sg1);
	GeometryExtend::scale(sg4, 0.5, 0.2);

	return 0;
}