1 | // -*- c++ -*- |
---|

2 | /** |
---|

3 | Implementation of a bounding box of plainvectors. |
---|

4 | |
---|

5 | */ |
---|

6 | #ifndef HUGO_BOUNDINGBOX_H |
---|

7 | #define HUGO_BOUNDINGBOX_H |
---|

8 | |
---|

9 | |
---|

10 | #include <xy.h> |
---|

11 | |
---|

12 | namespace hugo { |
---|

13 | |
---|

14 | template<typename T> |
---|

15 | class BoundingBox { |
---|

16 | xy<T> bottomleft, topright; |
---|

17 | bool _empty; |
---|

18 | public: |
---|

19 | |
---|

20 | ///Default constructor: an empty bounding box |
---|

21 | BoundingBox() { _empty = true; } |
---|

22 | |
---|

23 | ///Constructing the instance from one point |
---|

24 | BoundingBox(xy<T> a) { bottomleft=topright=a; _empty = false; } |
---|

25 | |
---|

26 | ///Is there any point added |
---|

27 | bool empty() const { |
---|

28 | return _empty; |
---|

29 | } |
---|

30 | |
---|

31 | ///Gives back the bottom left corner (if the bounding box is empty, then the return value is not defined) |
---|

32 | xy<T> bottomLeft() const { |
---|

33 | return bottomleft; |
---|

34 | }; |
---|

35 | |
---|

36 | ///Gives back the top right corner (if the bounding box is empty, then the return value is not defined) |
---|

37 | xy<T> topRight() const { |
---|

38 | return topright; |
---|

39 | }; |
---|

40 | |
---|

41 | ///Checks whether a point is inside a bounding box |
---|

42 | bool inside(const xy<T>& u){ |
---|

43 | if (_empty) |
---|

44 | return false; |
---|

45 | else{ |
---|

46 | return ((u.x-bottomleft.x)*(topright.x-u.x) >= 0 && |
---|

47 | (u.y-bottomleft.y)*(topright.y-u.y) >= 0 ); |
---|

48 | } |
---|

49 | } |
---|

50 | |
---|

51 | ///Increments a bounding box with a point |
---|

52 | BoundingBox& operator +=(const xy<T>& u){ |
---|

53 | if (_empty){ |
---|

54 | bottomleft=topright=u; |
---|

55 | _empty = false; |
---|

56 | } |
---|

57 | else{ |
---|

58 | if (bottomleft.x > u.x) bottomleft.x = u.x; |
---|

59 | if (bottomleft.y > u.y) bottomleft.y = u.y; |
---|

60 | if (topright.x < u.x) topright.x = u.x; |
---|

61 | if (topright.y < u.y) topright.y = u.y; |
---|

62 | } |
---|

63 | return *this; |
---|

64 | }; |
---|

65 | |
---|

66 | ///Sums a bounding box and a point |
---|

67 | BoundingBox operator +(const xy<T>& u){ |
---|

68 | BoundingBox b = *this; |
---|

69 | return b += u; |
---|

70 | }; |
---|

71 | |
---|

72 | ///Increments a bounding box with an other bounding box |
---|

73 | BoundingBox& operator +=(const BoundingBox &u){ |
---|

74 | if ( !u.empty() ){ |
---|

75 | *this += u.bottomLeft(); |
---|

76 | *this += u.topRight(); |
---|

77 | } |
---|

78 | return *this; |
---|

79 | }; |
---|

80 | |
---|

81 | ///Sums two bounding boxes |
---|

82 | BoundingBox operator +(const BoundingBox& u){ |
---|

83 | BoundingBox b = *this; |
---|

84 | return b += u; |
---|

85 | }; |
---|

86 | |
---|

87 | };//class BoundingBox |
---|

88 | |
---|

89 | |
---|

90 | } //namespace hugo |
---|

91 | |
---|

92 | #endif //HUGO_BOUNDINGBOX_H |
---|