contrib/include/wx/fl/gcupdatesmgr.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        No names yet.
   3 // Purpose:     Contrib. demo
   4 // Author:      Aleksandras Gluchovas
   5 // Modified by:
   6 // Created:     19/10/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Aleksandras Gluchovas
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef __GCUPDATESMGR_G__
  13 #define __GCUPDATESMGR_G__
  14
  15 #ifdef __GNUG__
  16     #pragma interface "gcupdatesmgr.h"
  17 #endif
  18
  19 #include "wx/fl/controlbar.h"
  20 #include "wx/fl/updatesmgr.h"
  21
  22 #include "wx/fl/garbagec.h"
  23
  24 /*
  25  * class implements optimized logic for refreshing
  26  * areas of frame layout - which actually need to be updated.
  27  * Is used as default updates-manager by wxFrameLayout.
  28  *
  29  * it is called "Garbage Collecting" u.mgr for it's implementation
  30  * tries to find out dependencies between bars, and to order
  31  * them ito "hierarchy", this hierarchical sorting resembles
  32  * implemenation of heap-garbage collectors, which resolve
  33  * dependencies between references.
  34  *
  35  * Example: there are situations where the order of moving
  36  *          the windows does matter:
  37  *
  38  *   case 1)
  39  *      ------              ---
  40  *      | A      |                  |B|
  41  *              ------   --->   | |
  42  *                      ---                     --- ------
  43  *                      |B|                             | A  |
  44  *                      | |                             ------
  45  *                      ---
  46  *                                              (future)
  47  *         (past)
  48  *
  49  *  past/future positions of A and B windows completely overlapp, i.e.
  50  *  depend on each other, and there is not solution for
  51  *  moving the windows witout refreshing both of them,
  52  *  -- we have cyclic dependency here. The gc. alg will
  53  *  find this cyclic dependecy and will force "refresh"
  54  *  after movement.
  55  *
  56  *   case 2)
  57  *
  58  *      ------
  59  *      | A      |
  60  *              ------   --->
  61  *                      ---
  62  *                      |B|                                        ------
  63  *                      | |                                        | A  |
  64  *                      ---                                        ------
  65  *                                               ---
  66  *                                               |B|
  67  *                                               | |
  68  *                                           ---
  69  *
  70  *                                              (future)
  71  *         (past)
  72  *
  73  *  in this case past/future positions do not overlapp, thus
  74  *  it's enough only to move windows, without refreshing them.
  75  *  GC will "notice" it.
  76  *
  77  *  there is also third case, when overlapping is partial
  78  *  in this case the refershing can be also avoided by
  79  *  moving windows in the order of "most-dependant" towards the
  80  *  "least-dependent". GC handles this automatically, by
  81  *  sorting windows by their dependency-level (or "hierarchy")
  82  *
  83  *  See garbagec.h for more details of this method, garbagec.h/cpp
  84  *  implement sorting of generic-dependencies (does not deal
  85  *  with graphical objects directly)
  86  *
  87  *  Summary: improves performance when complex/large windows are
  88  *           moved around, by reducing number of repaints. Also helps
  89  *           to avoid dirty non-client areas of moved windows
  90  *           in some special cases of "overlapping anomalies"
  91  */
  92
  93 class cbGCUpdatesMgr : public cbSimpleUpdatesMgr
  94 {
  95         DECLARE_DYNAMIC_CLASS( cbGCUpdatesMgr )
  96 protected:
  97
  98         GarbageCollector mGC;
  99
 100         void DoRepositionItems( wxList& items );
 101
 102         void AddItem( wxList&     itemList,
 103                                   cbBarInfo*  pBar,
 104                           cbDockPane* pPane,
 105                                   wxRect&     curBounds,
 106                                   wxRect&     prevBounds );
 107
 108 public:
 109
 110         cbGCUpdatesMgr(void) {}
 111
 112         cbGCUpdatesMgr( wxFrameLayout* pPanel );
 113
 114         // notificiactions received from Frame Layout :
 115
 116         virtual void OnStartChanges();
 117
 118         // refreshes parts of the frame layout, which need an update
 119         virtual void UpdateNow();
 120 };
 121
 122 #endif /* __GCUPDATESMGR_G__ */
 123