Android: added function to optimize complex regions

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12760 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 24 insertions, 7 deletions

diff --git a/src/drivers/Android/Fl_Android_Graphics_Clipping.H b/src/drivers/Android/Fl_Android_Graphics_Clipping.H
index 803548bab..7c88b54a5 100644
--- a/src/drivers/Android/Fl_Android_Graphics_Clipping.H
+++ b/src/drivers/Android/Fl_Android_Graphics_Clipping.H
@@ -69,6 +69,7 @@ public:
   void set_ltrb(int l, int t, int r, int b);
   virtual void set(const Fl_Rect_Region &r);
   virtual int intersect_with(const Fl_Rect_Region &r);
+  void add_to_bbox(const Fl_Rect_Region &r);
 
   virtual void print(const char*) const;
 
@@ -87,14 +88,29 @@ private:
  * rectangular, is_simple() returns 1 and the rectangle can be used just
  * as in Fl_Rect_Region.
  *
- * If a more complex representation is needed, the first list of
- * subregions is organizen in horizontal strips. The root region rect
- * will contain the outline of all subregions, and the subregions
- * will either be simple rectangles, or they will contain a second
- * level of subregions, subdividing the horizontal region into vertical
- * columns.
+ * If a more complex representation is needed, subregions are created which are
+ * guaranteed to lie within the bounding box of the current region. Subregions
+ * themselves can again contain sub-subregions to describe the entire clipping
+ * region, effectively creating a tree where the leafs contain the rectangles
+ * that together describe the clipping area.
+ *
+ * To make life easier, Fl_Complex_Region provides two types of iterator to
+ * travers the entire tree.
+ *
+ * 1. Fl_Complex_Region itself is compatible to C++11 range-based loops and
+ *    can bewalked simply by writing ``for (auto &&it: rgn) { ... }``.
+ *
+ * 2. Fl_Complex_Region provides an alternative iterator that loop only through
+ *    leafs that intersects with a given rectangle. The returned object
+ *    provides access to the readily clipped rectangle.
+ *
+ * @code
+ * Fl_Complex_Region rgn(something);
+ * for (auto &&it: rgn.iterate(Fl_Rect_Region(0, 0, 100, 100)) {
+ *    draw_something(it->rect());
+ * }
+ * @endcode
  *
- * When reading, the tree can be easily walked using recursion.
  */
 class Fl_Complex_Region : public Fl_Rect_Region
 {
@@ -156,6 +172,7 @@ protected:
   void print_data(int indent) const;
   int subtract_smaller_region(const Fl_Rect_Region &r);
   Fl_Complex_Region *add_subregion();
+  void compress();
 
   Fl_Complex_Region *pSubregion = 0L;
   Fl_Complex_Region *pParent = 0L;