KDecoration::unobscuredRegion(), for B2 titlebar unhiding.

svn path=/trunk/kdebase/kwin/; revision=262494

bridge.cpp

@@ -126,4 +126,31 @@ void Bridge::helperShowHide( bool show )
         c->rawHide();
     }
 
+QRegion Bridge::unobscuredRegion( const QRegion& r ) const
+    {
+    QRegion reg( r );
+    const ClientList stacking_order = c->workspace()->stackingOrder();
+    ClientList::ConstIterator it = stacking_order.find( c );
+    ++it;
+    for(;
+         it != stacking_order.end();
+         ++it )
+        {
+        /* the clients all have their mask-regions in local coords
+	   so we have to translate them to a shared coord system
+	   we choose ours */
+	int dx = (*it)->x() - c->x();
+	int dy = (*it)->y() - c->y();
+	QRegion creg = (*it)->mask();
+	creg.translate(dx, dy);
+	reg -= creg;
+	if (reg.isEmpty())
+            {
+	    // early out, we are completely obscured
+	    break;
+	    }
+        }
+    return reg;
+    }
+
 } // namespace

bridge.h

@@ -46,6 +46,7 @@ class Bridge : public KDecorationBridge
         virtual bool isPreview() const;
         virtual QRect geometry() const;
         virtual QRect iconGeometry() const;
+        virtual QRegion unobscuredRegion( const QRegion& r ) const;
         virtual QWidget* workspaceWidget() const;
         virtual void closeWindow();
         virtual void maximize( MaximizeMode mode );

client.cpp

@@ -437,6 +437,7 @@ void Client::updateShape()
 
 void Client::setMask( const QRegion& reg, int mode )
     {
+    _mask = reg;
     if( reg.isNull())
         XShapeCombineMask( qt_xdisplay(), frameId(), ShapeBounding, 0, 0,
             None, ShapeSet );
@@ -462,6 +463,13 @@ void Client::setMask( const QRegion& reg, int mode )
         }
     }
 
+QRegion Client::mask() const
+    {
+    if( _mask.isEmpty())
+        return QRegion( 0, 0, width(), height());
+    return _mask;
+    }
+
 void Client::hideClient( bool hide )
     {
     if( hidden == hide )

client.h

@@ -179,6 +179,7 @@ class Client : public QObject, public KDecorationDefines
         void demandAttention( bool set = true );
 
         void setMask( const QRegion& r, int mode = X::Unsorted );
+        QRegion mask() const;
 
         void updateDecoration( bool check_workspace_pos, bool force = false );
         void checkBorderSizes();
@@ -463,6 +464,7 @@ class Client : public QObject, public KDecorationDefines
         int block_geometry; // >0 - new geometry is remembered, but not actually set
         bool shade_geometry_change;
         int border_left, border_right, border_top, border_bottom;
+        QRegion _mask;
         friend struct FetchNameInternalPredicate;
         void show() { assert( false ); } // SELI remove after Client is no longer QWidget
         void hide() { assert( false ); }

clients/b2/b2client.cpp

@@ -785,7 +785,6 @@ void B2Client::slotReset()
 
 void B2Client::unobscureTitlebar()
 {
-#if 0 // TODO JUMPYTITLEBAR
     /* we just noticed, that we got obscured by other windows
        so we look at all windows above us (stacking_order) merging their
        masks, intersecting it with our titlebar area, and see if we can
@@ -795,23 +794,7 @@ void B2Client::unobscureTitlebar()
     }
     in_unobs = 1;
     QRegion reg(QRect(0,0,width(), buttonSize + 4));
-    ClientList::ConstIterator it = workspace()->stackingOrder().find(this);
-    ++it;
-    while (it != workspace()->stackingOrder().end()) {
-        /* the clients all have their mask-regions in local coords
-	   so we have to translate them to a shared coord system
-	   we choose ours */
-	int dx = (*it)->x() - x();
-	int dy = (*it)->y() - y();
-	QRegion creg = (*it)->getMask();
-	creg.translate(dx, dy);
-	reg -= creg;
-	if (reg.isEmpty()) {
-	    // early out, we are completely obscured
-	    break;
-	}
-	++it;
-    }
+    reg = unobscuredRegion( reg );
     if (!reg.isEmpty()) {
         // there is at least _one_ pixel from our title area, which is not
 	// obscured, we use the first rect we find
@@ -820,7 +803,6 @@ void B2Client::unobscureTitlebar()
 	titleMoveAbs(reg.boundingRect().x());
     }
     in_unobs = 0;
-#endif
 }
 
 static void redraw_pixmaps()
@@ -1123,8 +1105,6 @@ B2Titlebar::B2Titlebar(B2Client *parent)
 	    QSizePolicy::Expanding, QSizePolicy::Fixed);
 }
 
-// TODO JUMPYTITLEBAR This is not useful until titlebar revealing can be reenabled
-
 bool B2Titlebar::x11Event(XEvent *e)
 {
     if (!set_x11mask) {

kcmkwin/kwindecoration/preview.cpp

@@ -163,6 +163,8 @@ void KDecorationPreview::setPreviewMask( const QRegion& reg, int mode, bool acti
 	    xrects, rects.count(), ShapeSet, mode );
         delete[] xrects;
         }
+    if( active )
+        mask = reg; // keep shape of the active window for unobscuredRegion()
     }
 
 QRect KDecorationPreview::windowGeometry( bool active ) const
@@ -171,6 +173,24 @@ QRect KDecorationPreview::windowGeometry( bool active ) const
     return widget->geometry();
     }
 
+QRegion KDecorationPreview::unobscuredRegion( bool active, const QRegion& r ) const
+    {
+    if( active ) // this one is not obscured
+        return r;
+    else
+        {
+        // copied from KWin core's code
+        QRegion ret = r;
+        QRegion r2 = mask;
+        if( r2.isEmpty())
+            r2 = QRegion( windowGeometry( true ));
+        r2.translate( windowGeometry( true ).x() - windowGeometry( false ).x(),
+            windowGeometry( true ).y() - windowGeometry( false ).y());
+        ret -= r2;
+        return ret;
+        }
+    }
+
 KDecorationPreviewBridge::KDecorationPreviewBridge( KDecorationPreview* p, bool a )
     :   preview( p ), active( a )
     {
@@ -303,6 +323,11 @@ QRect KDecorationPreviewBridge::iconGeometry() const
     return QRect();
     }
 
+QRegion KDecorationPreviewBridge::unobscuredRegion( const QRegion& r ) const
+    {
+    return preview->unobscuredRegion( active, r );
+    }
+
 QWidget* KDecorationPreviewBridge::workspaceWidget() const
     {
     return preview;

kcmkwin/kwindecoration/preview.h

@@ -47,6 +47,7 @@ class KDecorationPreview
         void enablePreview();
         void disablePreview();
         void setPreviewMask( const QRegion&, int, bool );
+        QRegion unobscuredRegion( bool, const QRegion& ) const;
         QRect windowGeometry( bool ) const;
     protected:
         virtual void resizeEvent( QResizeEvent* );
@@ -56,6 +57,7 @@ class KDecorationPreview
         KDecorationPreviewBridge* bridge[NumWindows];
         KDecoration* deco[NumWindows];
         QLabel* no_preview;
+        QRegion mask;
     };
 
 class KDecorationPreviewBridge
@@ -87,6 +89,7 @@ class KDecorationPreviewBridge
         virtual bool isPreview() const;
         virtual QRect geometry() const;
         virtual QRect iconGeometry() const;
+        virtual QRegion unobscuredRegion( const QRegion& r ) const;
         virtual QWidget* workspaceWidget() const;
 	virtual void closeWindow();
 	virtual void maximize( MaximizeMode mode );

lib/kdecoration.cpp

@@ -203,6 +203,11 @@ QRect KDecoration::iconGeometry() const
     return bridge_->iconGeometry();
     }
 
+QRegion KDecoration::unobscuredRegion( const QRegion& r ) const
+    {
+    return bridge_->unobscuredRegion( r );
+    }
+
 QWidget* KDecoration::workspaceWidget() const
     {
     return bridge_->workspaceWidget();

lib/kdecoration.h

@@ -416,6 +416,15 @@ class KDecoration
 	 * the geometry may be null.
 	 */
         QRect iconGeometry() const;
+        /**
+         * Returns the intersection of the given region with the region left
+         * unobscured by the windows stacked above the current one. You can use
+         * this function to, for example, try to keep the titlebar visible if
+         * there is an hole available. The region returned is in the coordinate
+         * space of the decoration.
+         * @param r The region you want to check for holes
+         */
+        QRegion unobscuredRegion( const QRegion& r ) const;
 	/**
 	 * Returns the main workspace widget. The main purpose of this function is to
 	 * allow painting the minimize animation or the transparent move bound on it.

lib/kdecoration_p.h

@@ -83,6 +83,7 @@ class KDecorationBridge : public KDecorationDefines
         virtual bool isPreview() const = 0;
         virtual QRect geometry() const = 0;
         virtual QRect iconGeometry() const = 0;
+        virtual QRegion unobscuredRegion( const QRegion& r ) const = 0;
         virtual QWidget* workspaceWidget() const = 0;
 	virtual void closeWindow() = 0;
 	virtual void maximize( MaximizeMode mode ) = 0;