Add support for XComposite translucency to the Konsole KPart.

The decision to support translucent painting is made at part 
creation depending on whether the hosting application is using 
an ARGB visual and a composition manager has claimed the re-
levant X selection (via KWindowSystem).


svn path=/trunk/KDE/kdebase/apps/konsole/; revision=758145

src/Part.cpp

@@ -23,11 +23,13 @@
 // Qt
 #include <QtCore/QStringList>
 
+
 // KDE
 #include <KAction>
 #include <KActionCollection>
 #include <KDebug>
 #include <KLocale>
+#include <KWindowSystem>
 #include <kdeversion.h>
 
 // Konsole
@@ -39,9 +41,16 @@
 #include "Session.h"
 #include "SessionController.h"
 #include "SessionManager.h"
+#include "TerminalDisplay.h"
 #include "ViewManager.h"
 #include "MainWindow.h"
 
+// X
+#ifdef Q_WS_X11
+#include <X11/Xlib.h>
+#include <X11/extensions/Xrender.h>
+#endif
+
 extern "C"
 {
     // entry point for Konsole part library,
@@ -70,6 +79,8 @@ Part::Part(QWidget* parentWidget , QObject* parent)
   ,_pluggedController(0)
   ,_manageProfilesAction(0)
 {
+    TerminalDisplay::HAVE_TRANSPARENCY = transparencyAvailable();
+
 	// setup global actions
 	createGlobalActions();
 
@@ -109,6 +120,35 @@ void Part::setupActionsForSession(SessionController* session)
 	KActionCollection* collection = session->actionCollection();
 	collection->addAction("manage-profiles",_manageProfilesAction);
 }
+bool Part::transparencyAvailable()
+{
+#ifdef Q_WS_X11
+    bool ARGB = false;
+
+    int screen = QX11Info::appScreen();
+    bool depth = (QX11Info::appDepth() == 32);
+
+    Display* display = QX11Info::display();
+    Visual* visual = static_cast<Visual*>(QX11Info::appVisual(screen));
+
+    XRenderPictFormat* format = XRenderFindVisualFormat(display, visual);
+
+    if (depth && format->type == PictTypeDirect && format->direct.alphaMask)
+    {
+        ARGB = true;
+    }
+
+    if (ARGB)
+    {
+        return KWindowSystem::compositingActive();
+    }
+    else
+#endif
+    {
+        return false;
+    }
+}
+
 bool Part::openFile()
 {
     return false;