| // Copyright (C) 2011 Davis E. King ([email protected]) | |
| // License: Boost Software License See LICENSE.txt for the full license. | |
| namespace dlib | |
| { | |
| // ---------------------------------------------------------------------------------------- | |
| class border_enumerator | |
| { | |
| /*! | |
| POINTERS AND REFERENCES TO INTERNAL DATA | |
| All operations on this object other than calling element() invalidate | |
| pointers and references to internal data. | |
| WHAT THIS OBJECT REPRESENTS | |
| This object is an enumerator over the border points of a rectangle. | |
| !*/ | |
| public: | |
| border_enumerator( | |
| ); | |
| /*! | |
| ensures | |
| - #move_next() == false | |
| (i.e. this object is "empty" and won't enumerate anything) | |
| - current_element_valid() == false | |
| - at_start() == true | |
| - size() == 0 | |
| !*/ | |
| border_enumerator( | |
| const rectangle& rect, | |
| unsigned long border_size | |
| ); | |
| /*! | |
| ensures | |
| - This object will enumerate over the border points which are inside rect | |
| but within border_size of the edge. For example, if border_size == 1 | |
| then it enumerates over the single point wide strip of points all around | |
| the interior edge of rect. | |
| - current_element_valid() == false | |
| - at_start() == true | |
| - size() == rect.area() - shrink_rect(rect,border_size).area() | |
| (i.e. the number of points in the border area of rect) | |
| !*/ | |
| border_enumerator( | |
| const rectangle& rect, | |
| const rectangle& non_border_region | |
| ); | |
| /*! | |
| ensures | |
| - This object will enumerate over all points which are in rect but | |
| not in non_border_region. | |
| - current_element_valid() == false | |
| - at_start() == true | |
| - size() == rect.area() - rect.intersect(non_border_region).area() | |
| !*/ | |
| bool at_start ( | |
| ) const; | |
| /*! | |
| ensures | |
| - returns true if *this represents one position before the first point | |
| (this would also make the current element invalid) else returns false | |
| !*/ | |
| void reset ( | |
| ); | |
| /*! | |
| ensures | |
| - #current_element_valid() == false | |
| - #at_start() == true | |
| !*/ | |
| bool current_element_valid( | |
| ) const; | |
| /*! | |
| ensures | |
| - returns true if we are currently at a valid element else | |
| returns false | |
| !*/ | |
| bool move_next( | |
| ); | |
| /*! | |
| ensures | |
| - moves to the next element. i.e. #element() will now | |
| return the next border point. | |
| - the return value will be equal to #current_element_valid() | |
| - #at_start() == false | |
| - returns true if there is another element | |
| - returns false if there are no more elements in the container | |
| !*/ | |
| size_t size ( | |
| ) const; | |
| /*! | |
| ensures | |
| - returns the number of border points | |
| !*/ | |
| const point& element ( | |
| ) const; | |
| /*! | |
| requires | |
| - current_element_valid() == true | |
| ensures | |
| - returns the current border point | |
| !*/ | |
| }; | |
| // ---------------------------------------------------------------------------------------- | |
| } | |