1 files changed, 67 insertions, 0 deletions
diff --git a/meowpp/geo/Vector2D.h b/meowpp/geo/Vector2D.h
new file mode 100644
index 0000000..0b18138
--- /dev/null
+++ b/meowpp/geo/Vector2D.h
@@ -0,0 +1,67 @@
+#ifndef   Vector2D_H__
+#define   Vector2D_H__
+
+#include <cmath>
+#include "../utility.h"
+
+namespace meow{
+
+  template<class Scalar>
+  class Vector2D{
+    private:
+      Scalar _x, _y, _w;
+    public:
+      //
+      Vector2D(): _x(0), _y(0), _w(0){ }
+      Vector2D(Scalar const& x,
+               Scalar const& y)  : _x(   x), _y(   y), _w(   0){ }
+      Vector2D(Scalar const& x,
+               Scalar const& y,
+               Scalar const& w)  : _x(   x), _y(   y), _w(   w){ }
+      Vector2D(Vector2D const& v): _x(v._x), _y(v._y), _w(v._w){ }
+      //
+      Scalar const& x() const{ return _x; }
+      Scalar const& y() const{ return _y; }
+      Scalar const& w() const{ return _w; }
+      Scalar      & x(Scalar const& s){ _x = s; return _x; }
+      Scalar      & y(Scalar const& s){ _y = s; return _y; }
+      Scalar      & w(Scalar const& s){ _w = s; return _w; }
+      Vector2D& operator()(Scalar const& x, Scalar const& y)                 { _x = x; _y = y;         return *this; }
+      Vector2D& operator()(Scalar const& x, Scalar const& y, Scalar const& w){ _x = x; _y = y; _w = w; return *this; }
+      Scalar&       operator[](size_t n)      { return (n == 0 ? _x : (n == 1 ? _y : _w)); }
+      Scalar const& operator[](size_t n) const{ return (n == 0 ? _x : (n == 1 ? _y : _w)); }
+      //
+      Vector2D operator-() const{ return Vector2D(-_x, -_y, _w); }
+      Vector2D operator~() const{ return Vector2D(-_y,  _x, _w); }
+      //
+      Vector2D operator+(Vector2D const& v) const{ return Vector2D(_x + v._x, _y + v._y, _w); }
+      Vector2D operator-(Vector2D const& v) const{ return Vector2D(_x - v._x, _y - v._y, _w); }
+      Vector2D operator*(Scalar   const& s) const{ return Vector2D(_x *    s, _y *    s, _w); }
+      Vector2D operator/(Scalar   const& s) const{ return Vector2D(_x /    s, _y /    s, _w); }
+      //
+      Vector2D& operator+=(Vector2D const& v){ _x += v._x; _y += v._y; return *this; }
+      Vector2D& operator-=(Vector2D const& v){ _x -= v._x; _y -= v._y; return *this; }
+      Vector2D& operator*=(Scalar   const& s){ _x *=    s; _y *=    s; return *this; }
+      Vector2D& operator/=(Scalar   const& s){ _x /=    s; _y /=    s; return *this; }
+      //
+      Scalar dot  (Vector2D const& v) const{ return _x * v._x + _y * v._y; }
+      Scalar cross(Vector2D const& v) const{ return _x * v._y - _y * v._x; }
+      Scalar length () const{ return sqrt(squ(_x) + squ(_y)); }
+      Scalar length2() const{ return      squ(_x) + squ(_y) ; }
+      //
+      Vector2D normal() const{
+        Scalar len(length());
+        return Vector2D(_x / len, _y / len, _w);
+      }
+      Vector2D rotation(Scalar theta) const{
+        Vector2D i(cos(-theta), sin(-theta));
+        return Vector2D(i.dot(*this), i.cross(*this), _w);
+      }
+      Vector2D reflection(Vector2D const& v) const{
+        return v * v.dot(*this) * 2 / v.length2() - *this;
+      }
+  };
+
+}
+
+#endif // Vector2D_H__