contrib/docs/latex/fl/cbgcupdatesmgr.tex

   1 %
   2 % automatically generated by HelpGen $Revision$ from
   3 % gcupdatesmgr.h at 21/Jan/02 21:14:19
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   6
   7 \section{\class{cbGCUpdatesMgr}}\label{cbgcupdatesmgr}
   8
   9
  10 This class implements optimized logic for refreshing
  11 the areas of frame layout that actually need to be updated.
  12 It is used as the default updates manager by wxFrameLayout.
  13
  14 It is called 'Garbage Collecting' updates manager because
  15 its implementation tries to find out dependencies between bars,
  16 and to order them into a 'hierarchy'. This hierarchical sorting resembles
  17 the implementation of heap-garbage collectors, which resolve
  18 dependencies between references.
  19
  20 Example: there are situations where the order in which the user
  21 moves windows does matter.
  22
  23 \begin{verbatim}
  24   case 1)
  25      ------            ---
  26      | A     |             |B|
  27         ------     --->      | |
  28             ---               --- ------
  29             |B|                   | A  |
  30             | |                   ------
  31             ---
  32                         (future)
  33        (past)
  34 \end{verbatim}
  35
  36 Past/future positions of A and B windows completely overlap, i.e.
  37 depend on each other, and there is no solution for
  38 moving the windows without refreshing both of them
  39 -- we have a cyclic dependency here. The garbage collection algorithm will
  40 find this cyclic dependecy and will force refresh after movement.
  41
  42 \begin{verbatim}
  43   case 2)
  44
  45      ------
  46      | A     |
  47         ------     --->
  48             ---
  49             |B|                              ------
  50             | |                              | A  |
  51             ---                              ------
  52                          ---
  53                          |B|
  54                          | |
  55                          ---
  56
  57                         (future)
  58        (past)
  59 \end{verbatim}
  60
  61 In this case past/future positions do not overlap, so
  62 it is enough only to move windows without refreshing them.
  63 Garbage collection will 'notice' this.
  64
  65 There is also a third case, when overlapping is partial.
  66 In this case the refreshing can also be avoided by
  67 moving windows in the order of 'most-dependant' towards the
  68 'least-dependent'. GC handles this automatically, by
  69 sorting windows by their dependency-level (or 'hierarchy').
  70
  71 See garbagec.h for more details of this method; garbagec.h/cpp
  72 implement sorting of generic dependencies and does not deal
  73 with graphical objects directly.
  74
  75 Summary: garbage collection improves performance when complex or large
  76 windows are moved around, by reducing the number of repaints. It also helps
  77 to avoid dirty non-client areas of moved windows
  78 in some special cases of 'overlapping anomalies'.
  79
  80 \wxheading{Derived from}
  81
  82 \helpref{cbSimpleUpdatesMgr}{cbsimpleupdatesmgr}
  83
  84 \wxheading{Include files}
  85
  86 <wx/fl/gcupdatesmgr.h>
  87
  88 \wxheading{Data structures}
  89
  90 \latexignore{\rtfignore{\wxheading{Members}}}
  91
  92
  93 \membersection{cbGCUpdatesMgr::cbGCUpdatesMgr}\label{cbgcupdatesmgrcbgcupdatesmgr}
  94
  95 \func{}{cbGCUpdatesMgr}{\void}
  96
  97 Default constructor.
  98
  99
 100 \func{}{cbGCUpdatesMgr}{\param{wxFrameLayout* }{pPanel}}
 101
 102 Constructor, taking a frame layout.
 103
 104
 105 \membersection{cbGCUpdatesMgr::AddItem}\label{cbgcupdatesmgradditem}
 106
 107 \func{void}{AddItem}{\param{wxList\& }{itemList}, \param{cbBarInfo* }{pBar}, \param{cbDockPane* }{pPane}, \param{wxRect\& }{curBounds}, \param{wxRect\& }{prevBounds}}
 108
 109 Internal function for repositioning items.
 110
 111
 112 \membersection{cbGCUpdatesMgr::DoRepositionItems}\label{cbgcupdatesmgrdorepositionitems}
 113
 114 \func{void}{DoRepositionItems}{\param{wxList\& }{items}}
 115
 116 Internal function for repositioning items.
 117
 118
 119 \membersection{cbGCUpdatesMgr::OnStartChanges}\label{cbgcupdatesmgronstartchanges}
 120
 121 \func{void}{OnStartChanges}{\void}
 122
 123 Receives notifications from the frame layout.
 124
 125
 126 \membersection{cbGCUpdatesMgr::UpdateNow}\label{cbgcupdatesmgrupdatenow}
 127
 128 \func{void}{UpdateNow}{\void}
 129
 130 Refreshes the parts of the frame layout which need an update.
 131