capoint2d.h.svn-base

坦克大战游戏完整全套源代码

#ifndef __POINT_2_H_
#define __POINT_2_H_

#include <cmath>

namespace cAni
{
template< typename T >
struct _Point2
{
    T x, y;
    _Point2():x(0), y(0)
    {
    }
    _Point2(const _Point2 &p):x(p.x), y(p.y)
    {
    }
    _Point2(const T &_x, const T &_y):x(_x), y(_y)
    {
    }
    template<typename T2>
    _Point2& operator *= (const T2 &s)
    {
        x *= s;
        y *= s;
        return *this;
    }
    template<typename T2>
    _Point2 operator * (const T2 &s) const
    {
        _Point2 o = *this;
        o *= s;
        return o;
    }
    _Point2& operator += (const _Point2& a)
    {
        x += a.x;
        y += a.y;
        return *this;
    }
    _Point2 operator + (const _Point2& b) const
    {
        _Point2 o = *this;
        return o += b;
    }
    _Point2& operator -= (const _Point2& a)
    {
        x -= a.x;
        y -= a.y;
        return *this;
    }
    _Point2 operator - (const _Point2& b) const
    {
        _Point2 o = *this;
        return o -= b;
    }
    _Point2 operator - () const
    {
        return _Point2(-x, -y);
    }
    _Point2 operator / (const T &t) const
    {
        return _Point2(x/t, y/t);
    }
    _Point2& operator /= (const T &t)
    {
        x /= t;
        y /= t;
        return *this;
    }
    T DotProduct() const
    {
        return x * x + y * y;
    }
    T operator * (const _Point2 &a) const
    {
        return x * a.x + y * a.y;
    }
    friend const _Point2 CrossProduct(const _Point2 &a, const _Point2 &b)
    {
        return _Point2(a.x * b.y - b.x * a.y, b.x * a.y - a.x * b.y);
    }
    T operator ^ (const _Point2 &a) const
    {
        return x * a.y - y * a.x;
    }
    template< typename T2 >
    operator _Point2<T2> () const
    {
        _Point2<T2> t;
        t.x = static_cast<T2>(x);
        t.y = static_cast<T2>(y);
        return t;
    }
    T Length() const
    {
        return x + y;
    }
    _Point2& Normalize()
    {
        T len = Length();
        if (len == 0)
            return *this = _Point2();
        else
            return *this = *this / len;
    }
    _Point2& Normalize(T len)
    {
        T _len = Length();
        if (_len == 0)
            len = 0;
        else
            len /= _len;
        return *this = *this * len;
    }
    bool operator == (const _Point2 &a) const
    {
        return x == a.x && y == a.y;
    }
    bool operator != (const _Point2 &a) const
    {
        return ! (*this == a);
    }
};

template<>
inline float _Point2<float>::Length() const
{
    return sqrtf(DotProduct());
}
template<>
inline double _Point2<double>::Length() const
{
    return sqrt(DotProduct());
}
template<>
inline int _Point2<int>::Length() const
{
    return (int)sqrtf((float)DotProduct());
}
template<>
inline short _Point2<short>::Length() const
{
    return (short)sqrtf((float)DotProduct());
}
typedef _Point2< float > Point2f;
typedef _Point2< int > Point2i;
typedef _Point2< short > Point2s;

} // namespace cAni

#endif // __POINT_2_H_