1.1 --- a/lemon/xy.h	Tue Jul 26 13:15:13 2005 +0000
     1.2 +++ b/lemon/xy.h	Tue Jul 26 14:31:29 2005 +0000
     1.3 @@ -306,7 +306,7 @@
     1.4        }
     1.5    
     1.6        ///Increments a bounding box with a point
     1.7 -      BoundingBox& operator +=(const xy<T>& u){
     1.8 +      BoundingBox& add(const xy<T>& u){
     1.9          if (_empty){
    1.10            bottom_left=top_right=u;
    1.11            _empty = false;
    1.12 @@ -320,17 +320,17 @@
    1.13          return *this;
    1.14        }
    1.15    
    1.16 -      ///Sums a bounding box and a point
    1.17 -      BoundingBox operator +(const xy<T>& u){
    1.18 -        BoundingBox b = *this;
    1.19 -        return b += u;
    1.20 -      }
    1.21 +//       ///Sums a bounding box and a point
    1.22 +//       BoundingBox operator +(const xy<T>& u){
    1.23 +//         BoundingBox b = *this;
    1.24 +//         return b += u;
    1.25 +//       }
    1.26  
    1.27        ///Increments a bounding box with an other bounding box
    1.28 -      BoundingBox& operator +=(const BoundingBox &u){
    1.29 +      BoundingBox& add(const BoundingBox &u){
    1.30          if ( !u.empty() ){
    1.31 -          *this += u.bottomLeft();
    1.32 -          *this += u.topRight();
    1.33 +          this->add(u.bottomLeft());
    1.34 +	  this->add(u.topRight());
    1.35          }
    1.36          return *this;
    1.37        }
    1.38 @@ -338,7 +338,20 @@
    1.39        ///Sums two bounding boxes
    1.40        BoundingBox operator +(const BoundingBox& u){
    1.41          BoundingBox b = *this;
    1.42 -        return b += u;
    1.43 +        return b.add(u);
    1.44 +      }
    1.45 +
    1.46 +
    1.47 +      ///Intersection of two bounding boxes
    1.48 +      BoundingBox operator &(const BoundingBox& u){
    1.49 +        BoundingBox b;
    1.50 +	b.bottom_left.x=std::max(this->bottom_left.x,u.bottom_left.x);
    1.51 +	b.bottom_left.y=std::max(this->bottom_left.y,u.bottom_left.y);
    1.52 +	b.top_right.x=std::min(this->top_right.x,u.top_right.x);
    1.53 +	b.top_right.y=std::min(this->top_right.y,u.top_right.y);
    1.54 +	b._empty = this->_empty || u._empty ||
    1.55 +	  b.bottom_left.x>top_right.x && b.bottom_left.y>top_right.y;
    1.56 +        return b;
    1.57        }
    1.58  
    1.59      };//class Boundingbox