1 files changed, 126 insertions, 0 deletions
diff --git a/ml/dlib/dlib/geometry/border_enumerator_abstract.h b/ml/dlib/dlib/geometry/border_enumerator_abstract.h
new file mode 100644
index 000000000..11118d571
--- /dev/null
+++ b/ml/dlib/dlib/geometry/border_enumerator_abstract.h
@@ -0,0 +1,126 @@
+// Copyright (C) 2011  Davis E. King (davis@dlib.net)
+// License: Boost Software License   See LICENSE.txt for the full license.
+#undef DLIB_BORDER_EnUMERATOR_ABSTRACT_H_
+#ifdef DLIB_BORDER_EnUMERATOR_ABSTRACT_H_
+
+#include "rectangle_abstract.h"
+
+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
+        !*/
+
+    };
+
+// ----------------------------------------------------------------------------------------
+
+}
+
+#endif // DLIB_BORDER_EnUMERATOR_ABSTRACT_H_
+
+