workspace/kwin/effects/test/howto.h

   1 /*****************************************************************
   2  KWin - the KDE window manager
   3  This file is part of the KDE project.
   4
   5 Copyright (C) 2006 Lubos Lunak <l.lunak@kde.org>
   6
   7 You can Freely distribute this program under the GNU General Public
   8 License. See the file "COPYING" for the exact licensing terms.
   9 ******************************************************************/
  10
  11 /*
  12
  13  Files howto.cpp and howto.h implement HowtoEffect, a commented demo compositing
  14  effect that fades out and again in a window after it has been activated.
  15
  16 */
  17
  18 #ifndef KWIN_HOWTO_H
  19 #define KWIN_HOWTO_H
  20
  21 // Include with base class for effects.
  22 #include <kwineffects.h>
  23
  24 // Everything in KWin is in a namespace. There's no need to prefix names
  25 // with KWin or K, there's no (big) need to care about symbol clashes.
  26 namespace KWin
  27 {
  28
  29 // The class implementing the effect.
  30 class HowtoEffect
  31 // Inherit from the base class for effects.
  32     : public Effect
  33     {
  34     public:
  35         // There are two kinds of functions in an effect:
  36
  37         // Functions related to painting: These allow the effect to affect painting.
  38
  39         // A pre-paint function. It tells the compositing code how the painting will
  40         // be affected by this effect.
  41         virtual void prePaintWindow( EffectWindow* w, WindowPrePaintData& data, int time );
  42
  43         // A paint function. It actually performs the modifications to the painting.
  44         virtual void paintWindow( EffectWindow* w, int mask, QRegion region, WindowPaintData& data );
  45
  46         // A post-paint function. It can be used for cleanups after painting, but with animations
  47         // it is also used to trigger repaints during the next painting pass by manually "damaging"
  48         // areas of the window.
  49         virtual void postPaintWindow( EffectWindow* w );
  50
  51         // Notification functions: These inform the effect about changes such as a new window
  52         // being activated.
  53
  54         // The given window has been closed.
  55         virtual void windowClosed( EffectWindow* c );
  56
  57         // The given window has been activated.
  58         virtual void windowActivated( EffectWindow* c );
  59     private:
  60         // The window that will be faded out and in again.
  61         EffectWindow* fade_window;
  62
  63         // The progress of the fading.
  64         int progress;
  65     };
  66
  67 } // namespace
  68
  69 #endif