Rework how window painting is disabled; now effects can indicate reasons they want particular windows painted or not.

This solves a few problems, but may need revisiting in the future.

svn path=/branches/work/kwin_composite/; revision=632581

COMPOSITE_TODO

@@ -161,7 +161,7 @@ Effects framework TODO
         which means that if an effect sets PAINT_WINDOW_TRANSFORMED it needs to set it
         also in prePaintScreen()
 
-* PAINT_WINDOW_DISABLED turning off from effects needs some utility functions
+* PAINT_DISABLED turning off from effects needs some improvement
     - a window may have painting disabled for various reasons and their numbers may increase
         over time
         - so e.g. an effect showing minimized windows cannot simply turn off DISABLED

effects.cpp

@@ -443,6 +443,16 @@ EffectWindow::EffectWindow()
     {
     }
 
+void EffectWindow::enablePainting( int reason )
+    {
+    sceneWindow()->enablePainting( reason );
+    }
+
+void EffectWindow::disablePainting( int reason )
+    {
+    sceneWindow()->disablePainting( reason );
+    }
+
 int EffectWindow::desktop() const
     {
     return toplevel->desktop();

effects.h

@@ -169,6 +169,8 @@ class EffectWindow
         EffectWindow();
         const Toplevel* window() const;
         Toplevel* window();
+        void enablePainting( int reason );
+        void disablePainting( int reason );
         bool isOnDesktop( int d ) const;
         bool isOnCurrentDesktop() const;
         bool isOnAllDesktops() const;

effects/desktopchangeslide.cpp

@@ -40,9 +40,9 @@ void DesktopChangeSlideEffect::prePaintWindow( EffectWindow* w, int* mask, QRegi
         if( painting_old_desktop )
             {
             if( w->isOnDesktop( old_desktop ) && !w->isOnCurrentDesktop())
-                *mask &= ~Scene::PAINT_WINDOW_DISABLED; // paint windows on old desktop
+                w->enablePainting( Scene::Window::PAINT_DISABLED_BY_DESKTOP );
             else
-                *mask |= Scene::PAINT_WINDOW_DISABLED;
+                w->disablePainting( Scene::Window::PAINT_DISABLED_BY_DESKTOP );
             }
         else
             {

effects/fadeout.cpp

@@ -24,7 +24,8 @@ void FadeOutEffect::prePaintWindow( EffectWindow* w, int* mask, QRegion* region,
         if( windows[ w  ] > 0 )
             {
             *mask |= Scene::PAINT_WINDOW_TRANSLUCENT;
-            *mask &= ~( Scene::PAINT_WINDOW_OPAQUE | Scene::PAINT_WINDOW_DISABLED );
+            *mask &= ~Scene::PAINT_WINDOW_OPAQUE;
+            w->enablePainting( Scene::Window::PAINT_DISABLED_BY_DELETE );
             }
         else
             {

effects/minimizeanimation.cpp

@@ -62,7 +62,7 @@ void MinimizeAnimationEffect::prePaintWindow( EffectWindow* w, int* mask, QRegio
             {
             // We'll transform this window
             *mask |= Scene::PAINT_WINDOW_TRANSFORMED;
-            *mask &= ~Scene::PAINT_WINDOW_DISABLED;
+            w->enablePainting( Scene::Window::PAINT_DISABLED_BY_MINIMIZE );
             }
         else
             // Animation just finished

effects/presentwindows.cpp

@@ -69,7 +69,7 @@ void PresentWindowsEffect::prePaintWindow( EffectWindow* w, int* mask, QRegion*
         {
         // This window will be transformed by the effect
         *mask |= Scene::PAINT_WINDOW_TRANSFORMED;
-        *mask &= ~Scene::PAINT_WINDOW_DISABLED;
+        w->enablePainting( Scene::Window::PAINT_DISABLED_BY_MINIMIZE );
         // If it's minimized window and effect is not fully active, then apply
         //  some transparency
         if( mActiveness < 1.0f && static_cast< Client* >( w->window() )->isMinimized() )

scene.cpp

@@ -160,12 +160,11 @@ void Scene::paintGenericScreen( int orig_mask, ScreenPaintData )
     foreach( Window* w, stacking_order ) // bottom to top
         {
         int mask = orig_mask | ( w->isOpaque() ? PAINT_WINDOW_OPAQUE : PAINT_WINDOW_TRANSLUCENT );
-        if( !w->isVisible())
-            mask |= PAINT_WINDOW_DISABLED;
+        w->resetPaintingEnabled();
         QRegion damage = infiniteRegion();
         // preparation step
         effects->prePaintWindow( effectWindow( w ), &mask, &damage, time_diff );
-        if( mask & PAINT_WINDOW_DISABLED )
+        if( !w->isPaintingEnabled())
             continue;
         paintWindow( w, mask, damage );
         }
@@ -191,12 +190,11 @@ void Scene::paintSimpleScreen( int orig_mask, QRegion region )
         if( region.isEmpty()) // completely clipped
             continue;
         int mask = orig_mask | ( w->isOpaque() ? PAINT_WINDOW_OPAQUE : PAINT_WINDOW_TRANSLUCENT );
-        if( !w->isVisible())
-            mask |= PAINT_WINDOW_DISABLED;
+        w->resetPaintingEnabled();
         QRegion damage = region;
         // preparation step
         effects->prePaintWindow( effectWindow( w ), &mask, &damage, time_diff );
-        if( mask & PAINT_WINDOW_DISABLED )
+        if( !w->isPaintingEnabled())
             continue;
         // If the window is transparent, the transparent part will be done
         // in the 2nd pass.
@@ -243,6 +241,7 @@ void Scene::finalPaintWindow( EffectWindow* w, int mask, QRegion region, WindowP
 Scene::Window::Window( Toplevel * c )
     : toplevel( c )
     , filter( ImageFilterFast )
+    , disable_painting( 0 )
     , shape_valid( false )
     {
     }
@@ -314,4 +313,33 @@ bool Scene::Window::isOpaque() const
     return toplevel->opacity() == 1.0 && !toplevel->hasAlpha();
     }
 
+bool Scene::Window::isPaintingEnabled() const
+    {
+    return !disable_painting;
+    }
+
+void Scene::Window::resetPaintingEnabled()
+    {
+    disable_painting = 0;
+    if( dynamic_cast< Deleted* >( toplevel ) != NULL )
+        disable_painting |= PAINT_DISABLED_BY_DELETE;
+    if( !toplevel->isOnCurrentDesktop())
+        disable_painting |= PAINT_DISABLED_BY_DESKTOP;
+    if( Client* c = dynamic_cast< Client* >( toplevel ))
+        {
+        if( c->isMinimized() )
+            disable_painting |= PAINT_DISABLED_BY_MINIMIZE;
+        }
+    }
+
+void Scene::Window::enablePainting( int reason )
+    {
+    disable_painting &= ~reason;
+    }
+
+void Scene::Window::disablePainting( int reason )
+    {
+    disable_painting |= reason;
+    }
+
 } // namespace

scene.h

@@ -58,18 +58,15 @@ class Scene
             PAINT_WINDOW_TRANSLUCENT    = 1 << 1,
             // Window will be painted with transformed geometry.
             PAINT_WINDOW_TRANSFORMED    = 1 << 2,
-            // When set, the window won't be painted (set by default
-            // for hidden windows, can be unset in pre-paint).
-            PAINT_WINDOW_DISABLED       = 1 << 3,
             // Paint only a region of the screen (can be optimized, cannot
             // be used together with TRANSFORMED flags).
-            PAINT_SCREEN_REGION         = 1 << 4,
+            PAINT_SCREEN_REGION         = 1 << 3,
             // Whole screen will be painted with transformed geometry.
-            PAINT_SCREEN_TRANSFORMED    = 1 << 5,
+            PAINT_SCREEN_TRANSFORMED    = 1 << 4,
             // At least one window will be painted with transformed geometry.
-            PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS = 1 << 6,
+            PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS = 1 << 5,
             // Clear whole background as the very first step, without optimizing it
-            PAINT_SCREEN_BACKGROUND_FIRST = 1 << 7
+            PAINT_SCREEN_BACKGROUND_FIRST = 1 << 6
             };
         // types of filtering available
         enum ImageFilterType { ImageFilterFast, ImageFilterGood };
@@ -132,6 +129,23 @@ class Scene::Window
         // access to the internal window class
         // TODO eventually get rid of this
         Toplevel* window();
+        // should the window be painted
+        bool isPaintingEnabled() const;
+        void resetPaintingEnabled();
+        // Flags explaining why painting should be disabled
+        enum
+            {
+            // Window will not be painted
+            PAINT_DISABLED              = 1 << 0,
+            // Window will not be painted because it is deleted
+            PAINT_DISABLED_BY_DELETE    = 1 << 1,
+            // Window will not be painted because of which desktop it's on
+            PAINT_DISABLED_BY_DESKTOP   = 1 << 2,
+            // Window will not be painted because it is minimized
+            PAINT_DISABLED_BY_MINIMIZE  = 1 << 3,
+            };
+        void enablePainting( int reason );
+        void disablePainting( int reason );
         // is the window visible at all
         bool isVisible() const;
         // is the window fully opaque
@@ -145,6 +159,7 @@ class Scene::Window
         Toplevel* toplevel;
         ImageFilterType filter;
     private:
+        int disable_painting;
         mutable QRegion shape_region;
         mutable bool shape_valid;
     };

scene_xrender.cpp

@@ -169,12 +169,11 @@ void SceneXrender::paintTransformedScreen( int orig_mask )
         if( region.isEmpty()) // completely clipped
             continue;
         int mask = orig_mask | ( w->isOpaque() ? PAINT_WINDOW_OPAQUE : PAINT_WINDOW_TRANSLUCENT );
-        if( !w->isVisible())
-            mask |= PAINT_WINDOW_DISABLED;
+        w->resetPaintingEnabled();
         QRegion damage = region;
         // preparation step
         effects->prePaintWindow( effectWindow( w ), &mask, &damage, time_diff );
-        if( mask & PAINT_WINDOW_DISABLED )
+        if( !w->isPaintingEnabled())
             continue;
         // If the window is transparent, the transparent part will be done
         // in the 2nd pass.