Что такое TPoint, как пользоваться и что подставлять.

function WindowFromPoint( Point: TPoint ): HWND;

"TPoint type defines a pixel location onscreen.
 
Unit
 
Types
 
struct TPoint
 
{
  TPoint() {}
  TPoint(int _x, int _y) : x(_x), y(_y) {}
  TPoint(POINT& pt)
  {
    x = pt.x;
    y = pt.y;
  }
  operator POINT() const
  {
    POINT pt;
    pt.x = x;
    pt.y = y;
    return pt;
  }
  int  x;
  int  y;
 
};

//-- user supplied -----------------------------------------------------------
namespace Types
{
  struct TPoint : public POINT
  {
    TPoint() { x = y = 0; }
    TPoint(int _x, int _y) { x=_x; y=_y; }
    TPoint(const POINT& pt)
    {
      x = pt.x;
      y = pt.y;
    }
    bool operator ==(const TPoint& pt) const
    {
      return (x == pt.x) && (y == pt.y);
    }
    bool operator !=(const TPoint& pt) const
    {
      return !(pt == *this);
    }
  };
 
  typedef TPoint tagPoint;
 
// ...
}

typedef struct tagPOINT
{
    LONG  x;
    LONG  y;
} POINT, *PPOINT, NEAR *NPPOINT, FAR *LPPOINT;

TPoint P;
P.x= 10;
P.y= 20;
 
HWND hwnd = WindowFromPoint(P);

HWND hwnd = WindowFromPoint(TPoint(10,20) );

HWND WindowFromPoint( POINT Point );