ryzom/server/src/entities_game_service/area_geometry.h

   1 // Ryzom - MMORPG Framework <http://dev.ryzom.com/projects/ryzom/>
   2 // Copyright (C) 2010  Winch Gate Property Limited
   3 //
   4 // This program is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU Affero General Public License as
   6 // published by the Free Software Foundation, either version 3 of the
   7 // License, or (at your option) any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU Affero General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU Affero General Public License
  15 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17
  18
  19 #ifndef RY_AREA_GEOMETRY_H
  20 #define RY_AREA_GEOMETRY_H
  21
  22
  23
  24 template<class T>
  25 struct CAreaCoords
  26 {
  27         CAreaCoords(){}
  28         CAreaCoords(T x, T y)
  29                 :X(x),Y(y){}
  30         T X;
  31         T Y;
  32
  33
  34         CAreaCoords<T> &operator*=(float scalar)
  35         {
  36                 X = T ( scalar * X);
  37                 Y = T ( scalar * Y);
  38                 return *this;
  39         }
  40
  41 };
  42
  43 template<class T>
  44 class CAreaQuad
  45 {
  46 public:
  47         bool contains( CAreaCoords<T> point )const
  48         {
  49                 uint32 nNbIntersection = 0;
  50                 for (uint i = 0; i < 4; ++i)
  51                 {
  52                         const CAreaCoords<T> &p1 = Vertices[i];
  53                         const CAreaCoords<T> &p2 = Vertices[(i+1)%4];
  54
  55                         if ( p1.Y - point.Y < T(0) && p2.Y-point.Y  < T(0) )
  56                                 continue;
  57                         if ( p1.Y-point.Y  > T(0) && p2.Y-point.Y > T(0) )
  58                                 continue;
  59                         T xinter = (sint32)( p1.X + (p2.X-p1.X) * ( double(point.Y - p1.Y) / double( p2.Y - p1.Y  ) ) );
  60                         if (xinter > point.X)
  61                                 ++nNbIntersection;
  62                 }
  63                 if ((nNbIntersection&1) == 1) // odd intersections so the vertex is inside
  64                         return true;
  65                 else
  66                         return false;
  67         }
  68         CAreaCoords<T> Vertices [4];
  69 };
  70
  71 template<class T>
  72 class CAreaRect
  73 {
  74 public:
  75         ///from a quad : build the bounding rect
  76         CAreaRect<T>( const CAreaQuad<T> & quad )
  77         {
  78                 Point.X = quad.Vertices[0].X;
  79                 Point.Y = quad.Vertices[0].Y;
  80                 CAreaCoords<T> topRight(quad.Vertices[0].X,quad.Vertices[0].Y);
  81
  82                 for ( uint i = 1; i < 3; i++ )
  83                 {
  84                         if ( Point.X > quad.Vertices[i].X )
  85                                 Point.X = quad.Vertices[i].X;
  86                         else if ( topRight.X < quad.Vertices[i].X )
  87                                 topRight.X = quad.Vertices[i].X;
  88
  89                         if ( Point.Y > quad.Vertices[i].Y )
  90                                 Point.Y = quad.Vertices[i].Y;
  91                         else if ( topRight.Y < quad.Vertices[i].Y )
  92                                 topRight.Y = quad.Vertices[i].Y;
  93                 }
  94                 Width = topRight.X - Point.X;
  95                 Height = topRight.Y - Point.Y;
  96         }
  97
  98         CAreaCoords<T> center()
  99         {
 100                 return CAreaCoords<T> ( Point.X + Width / 2,  Point.Y + Height / 2 );
 101         }
 102
 103         /// bottom left point
 104         CAreaCoords<T> Point;
 105         ///width
 106         T Width;
 107         T Height;
 108 };
 109
 110
 111
 112 #endif // RY_AREA_GEOMETRY_H
 113
 114 /* End of area_geometry.h */