Add composition manager detection and support to Trinity

This adds the methods required to make transparent widgets via alpha blending a reality
An additional widget class may be coming shortly


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdelibs@1246265 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

5 files changed, 316 insertions, 7 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3fd7da01c..941411514 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -548,6 +548,12 @@ if( XRENDER_FOUND )
   set( HAVE_XRENDER 1 )
 endif( XRENDER_FOUND )
 
+##### check for xcomposite #########################
+
+pkg_search_module( XCOMPOSITE xcomposite )
+if( XCOMPOSITE_FOUND )
+  set( HAVE_XCOMPOSITE 1 )
+endif( XCOMPOSITE_FOUND )
 
 ##### check for libxml-2.0 ######################
 
diff --git a/config.h.cmake b/config.h.cmake
index 719e324df..99562b3a6 100644
--- a/config.h.cmake
+++ b/config.h.cmake
@@ -665,6 +665,9 @@
 /* Defined if your system has XRender support */
 #cmakedefine HAVE_XRENDER 1
 
+/* Defined if your system has XComposite support */
+#cmakedefine HAVE_XCOMPOSITE 1
+
 /* Define to 1 if you have the `_getpty' function. */
 #cmakedefine HAVE__GETPTY 1
 
diff --git a/kdecore/CMakeLists.txt b/kdecore/CMakeLists.txt
index 3e37ed20c..efe2c8f3c 100644
--- a/kdecore/CMakeLists.txt
+++ b/kdecore/CMakeLists.txt
@@ -129,7 +129,7 @@ tde_add_library( ${target} SHARED AUTOMOC
   SOURCES ${${target}_SRCS}
   VERSION 4.2.0
   EMBED kdecorenetwork-static
-  LINK ltdlc-static ${KDESVGICONS} DCOP-shared kdefx-shared ${ZLIB_LIBRARIES} ${LIBIDN_LIBRARIES} ICE SM
+  LINK ltdlc-static ${KDESVGICONS} DCOP-shared kdefx-shared ${ZLIB_LIBRARIES} ${LIBIDN_LIBRARIES} ${XCOMPOSITE_LIBRARIES} ICE SM
   DEPENDENCIES dcopidl dcopidl2cpp
   DESTINATION ${LIB_INSTALL_DIR}
 )
@@ -199,3 +199,11 @@ tde_add_executable(kgrantpty SETUID
   SOURCES kgrantpty.c
   DESTINATION ${BIN_INSTALL_DIR}
 )
+
+##### kdetcompmgr #################################
+
+tde_add_executable( kdetcompmgr
+  SOURCES kdetcompmgr.cpp
+  LINK kdecore-shared
+  DESTINATION ${BIN_INSTALL_DIR}
+)
diff --git a/kdecore/kapplication.cpp b/kdecore/kapplication.cpp
index 292105835..7986079f4 100644
--- a/kdecore/kapplication.cpp
+++ b/kdecore/kapplication.cpp
@@ -125,6 +125,11 @@
 
 #ifdef Q_WS_X11
 #include <X11/Xlib.h>
+#ifdef COMPOSITE
+#include <X11/extensions/Xrender.h>
+#include <X11/extensions/Xcomposite.h>
+#include <dlfcn.h>
+#endif
 #include <X11/Xutil.h>
 #include <X11/Xatom.h>
 #include <X11/SM/SMlib.h>
@@ -175,6 +180,18 @@ static Atom atom_NetSupported;
 static Atom kde_xdnd_drop;
 #endif
 
+#ifdef Q_WS_X11
+static int composite_event, composite_error, composite_opcode;
+static bool x11_composite_error_generated;
+static int x11_error(Display *dpy, XErrorEvent *ev) {
+	if (ev->request_code == composite_opcode && ev->minor_code == X_CompositeRedirectSubwindows)
+	{
+		x11_composite_error_generated = true;
+		return 0;
+	}
+}
+#endif
+
 // duplicated from patched Qt, so that there won't be unresolved symbols if Qt gets
 // replaced by unpatched one
 KDECORE_EXPORT bool qt_qclipboard_bailout_hack = false;
@@ -602,6 +619,7 @@ KApplication::KApplication( int& argc, char** argv, const TQCString& rAppName,
   TQApplication( argc, argv, GUIenabled ), KInstance(rAppName),
 #ifdef Q_WS_X11
   display(0L),
+  argb_visual(false),
 #endif
   d (new KApplicationPrivate())
 {
@@ -622,11 +640,11 @@ KApplication::KApplication( int& argc, char** argv, const TQCString& rAppName,
 }
 
 KApplication::KApplication( bool allowStyles, bool GUIenabled ) :
-  TQApplication( *KCmdLineArgs::qt_argc(), *KCmdLineArgs::qt_argv(),
-                TRUE ),	// Qt4 requires that there always be a GUI
+  TQApplication( *KCmdLineArgs::qt_argc(), *KCmdLineArgs::qt_argv(), TRUE ),	// Qt4 requires that there always be a GUI
   KInstance( KCmdLineArgs::about),
 #ifdef Q_WS_X11
   display(0L),
+  argb_visual(false),
 #endif
   d (new KApplicationPrivate)
 {
@@ -648,9 +666,11 @@ KApplication::KApplication( bool allowStyles, bool GUIenabled ) :
 KApplication::KApplication( Display *dpy, Qt::HANDLE visual, Qt::HANDLE colormap,
 		            bool allowStyles ) :
   TQApplication( dpy, *KCmdLineArgs::qt_argc(), *KCmdLineArgs::qt_argv(),
-                visual, colormap ),
+                visual?visual:getX11RGBAVisual(dpy), colormap?colormap:getX11RGBAColormap(dpy) ),
   KInstance( KCmdLineArgs::about), display(0L), d (new KApplicationPrivate)
 {
+    if ((visual) && (colormap))
+        getX11RGBAInformation(dpy);
     aIconPixmap.pm.icon = 0L;
     aIconPixmap.pm.miniIcon = 0L;
     read_app_startup_id();
@@ -665,9 +685,11 @@ KApplication::KApplication( Display *dpy, Qt::HANDLE visual, Qt::HANDLE colormap
 KApplication::KApplication( Display *dpy, Qt::HANDLE visual, Qt::HANDLE colormap,
 		            bool allowStyles, KInstance * _instance ) :
   TQApplication( dpy, *KCmdLineArgs::qt_argc(), *KCmdLineArgs::qt_argv(),
-                visual, colormap ),
+                visual?visual:getX11RGBAVisual(dpy), colormap?colormap:getX11RGBAColormap(dpy) ),
   KInstance( _instance ), display(0L), d (new KApplicationPrivate)
 {
+    if ((visual) && (colormap))
+        getX11RGBAInformation(dpy);
     aIconPixmap.pm.icon = 0L;
     aIconPixmap.pm.miniIcon = 0L;
     read_app_startup_id();
@@ -684,6 +706,7 @@ KApplication::KApplication( bool allowStyles, bool GUIenabled, KInstance* _insta
   TQApplication( *KCmdLineArgs::qt_argc(), *KCmdLineArgs::qt_argv(),
                 GUIenabled ),
   KInstance( _instance ),
+  argb_visual(false),
 #ifdef Q_WS_X11
   display(0L),
 #endif
@@ -708,6 +731,7 @@ KApplication::KApplication(Display *display, int& argc, char** argv, const TQCSt
                            bool allowStyles, bool GUIenabled ) :
   TQApplication( display ), KInstance(rAppName),
   display(0L),
+  argb_visual(false),
   d (new KApplicationPrivate())
 {
     aIconPixmap.pm.icon = 0L;
@@ -1718,7 +1742,190 @@ public:
 };
 #endif
 
+#if defined(Q_WS_X11) && defined(COMPOSITE)
+bool KApplication::isCompositionManagerAvailable() {
+	KConfigGroup pConfig (KGlobal::config(), "General");
+	return pConfig.readBoolEntry("compositingManagerAvailable", false);
+
+return false;
+}
+
+bool KApplication::detectCompositionManagerAvailable(bool force_available) {
+	bool compositing_manager_available;
+	if (force_available) {
+		compositing_manager_available = true;
+	}
+	else {
+		// See if compositing has been enabled
+		KCmdLineArgs *qtargs = KCmdLineArgs::parsedArgs("qt");
+		char *displayname = 0;
+		if ( qtargs->isSet("display"))
+			displayname = qtargs->getOption( "display" ).data();
+			
+		Display *dpy = XOpenDisplay( displayname );
+	
+		x11_composite_error_generated = false;
+		compositing_manager_available = false;
+		XSetErrorHandler(x11_error);
+		if (!XQueryExtension (dpy, COMPOSITE_NAME, &composite_opcode, &composite_event, &composite_error)) {
+			XSetErrorHandler(NULL);
+			compositing_manager_available = false;
+		}
+		else {
+			Window root_window = XDefaultRootWindow(dpy);
+			XCompositeRedirectSubwindows(dpy, root_window, CompositeRedirectManual);
+			XSync(dpy, false);
+			if (x11_composite_error_generated == true) {
+				compositing_manager_available = true;
+			}
+			else {
+				XCompositeUnredirectSubwindows(dpy, root_window, CompositeRedirectManual);
+				compositing_manager_available = false;
+			}
+			XSetErrorHandler(NULL);
+			XCloseDisplay(dpy);
+		}
+	}
+	
+	KConfigGroup pConfig (KGlobal::config(), "General");
+	bool cmanager_enabled = pConfig.readBoolEntry("compositingManagerAvailable", false);
+	if (cmanager_enabled != compositing_manager_available) {
+		pConfig.writeEntry("compositingManagerAvailable", compositing_manager_available, true, true);
+	}
+	pConfig.sync();
+
+	return compositing_manager_available;
+}
+
+Display* KApplication::openX11RGBADisplay() {
+	KCmdLineArgs *qtargs = KCmdLineArgs::parsedArgs("qt");
+	char *displayname = 0;
+	if ( qtargs->isSet("display"))
+		displayname = qtargs->getOption( "display" ).data();
+		
+	Display *dpy = XOpenDisplay( displayname );
+	return dpy;
+}
+
+Qt::HANDLE KApplication::getX11RGBAVisual(Display *dpy) {
+	getX11RGBAInformation(dpy);
+	return argb_x11_visual;
+}
+
+Qt::HANDLE KApplication::getX11RGBAColormap(Display *dpy) {
+	getX11RGBAInformation(dpy);
+	return argb_x11_colormap;
+}
+
+bool KApplication::isX11CompositionAvailable() {
+	return argb_visual & isCompositionManagerAvailable();
+}
+
+void KApplication::getX11RGBAInformation(Display *dpy) {
+	if ( !dpy ) {
+		argb_visual = false;
+		return;
+	}
+	
+	int screen = DefaultScreen( dpy );
+	Colormap colormap = 0;
+	Visual *visual = 0;
+	int event_base, error_base;
+	
+	if ( XRenderQueryExtension( dpy, &event_base, &error_base ) ) {
+		int nvi;
+		XVisualInfo templ;
+		templ.screen  = screen;
+		templ.depth   = 32;
+		templ.c_class = TrueColor;
+		XVisualInfo *xvi = XGetVisualInfo( dpy, VisualScreenMask | VisualDepthMask
+				| VisualClassMask, &templ, &nvi );
+		
+		for ( int i = 0; i < nvi; i++ ) {
+			XRenderPictFormat *format = XRenderFindVisualFormat( dpy, xvi[i].visual );
+			if ( format->type == PictTypeDirect && format->direct.alphaMask ) {
+				visual = xvi[i].visual;
+				colormap = XCreateColormap( dpy, RootWindow( dpy, screen ), visual, AllocNone );
+				kdDebug() << "found visual with alpha support" << endl;
+				argb_visual = true;
+				break;
+			}
+		}
+	}
+	
+	if( argb_visual ) {
+		argb_x11_visual = Qt::HANDLE( visual );
+		argb_x11_colormap = Qt::HANDLE( colormap );
+		argb_visual = true;
+		return;
+	}
+	argb_visual = false;
+	return;
+}
+
+KApplication KApplication::KARGBApplicationObject( bool allowStyles ) {
+	KCmdLineArgs *qtargs = KCmdLineArgs::parsedArgs("qt");
+	bool argb_visual_available = false;
+	char *display = 0;
+	if ( qtargs->isSet("display"))
+		display = qtargs->getOption( "display" ).data();
+	
+	Display *dpy = XOpenDisplay( display );
+	if ( !dpy ) {
+		kdError() << "cannot connect to X server " << display << endl;
+		exit( 1 );
+	}
+	
+	int screen = DefaultScreen( dpy );
+	Colormap colormap = 0;
+	Visual *visual = 0;
+	int event_base, error_base;
+	
+	if ( XRenderQueryExtension( dpy, &event_base, &error_base ) ) {
+		int nvi;
+		XVisualInfo templ;
+		templ.screen  = screen;
+		templ.depth   = 32;
+		templ.c_class = TrueColor;
+		XVisualInfo *xvi = XGetVisualInfo( dpy, VisualScreenMask | VisualDepthMask
+				| VisualClassMask, &templ, &nvi );
+		
+		for ( int i = 0; i < nvi; i++ ) {
+			XRenderPictFormat *format = XRenderFindVisualFormat( dpy, xvi[i].visual );
+			if ( format->type == PictTypeDirect && format->direct.alphaMask ) {
+				visual = xvi[i].visual;
+				colormap = XCreateColormap( dpy, RootWindow( dpy, screen ), visual, AllocNone );
+				kdDebug() << "found visual with alpha support" << endl;
+				argb_visual_available = true;
+				break;
+			}
+		}
+	}
+	
+	if( argb_visual_available ) {
+		return KApplication( dpy, Qt::HANDLE( visual ), Qt::HANDLE( colormap ), allowStyles );
+	}
+	else {
+		return KApplication(allowStyles, true);
+	}
+}
+#else
+Qt::HANDLE KApplication::getX11RGBAVisual(char *display) {
+	return 0;
+}
+
+Qt::HANDLE KApplication::getX11RGBAColormap(char *display) {
+	return 0;
+}
 
+bool KApplication::isX11CompositionAvailable() {
+	return false;
+}
+
+KApplication KApplication::KARGBApplication( bool allowStyles ) {
+	return KApplication::KApplication(allowStyles, true);
+}
+#endif
 
 static bool kapp_block_user_input = false;
 
diff --git a/kdecore/kapplication.h b/kdecore/kapplication.h
index 93820b68d..00a6429da 100644
--- a/kdecore/kapplication.h
+++ b/kdecore/kapplication.h
@@ -48,6 +48,8 @@ class KSessionManaged;
 class KStyle;
 class KURL;
 
+#define COMPOSITE	// [FIXME] Autodetect composition support
+
 #define kapp KApplication::kApplication()
 
 class KApplicationPrivate;
@@ -113,6 +115,10 @@ public:
    * This constructor takes aboutData and command line
    *  arguments from KCmdLineArgs.
    *
+   *  If ARGB (transparent) widgets are to be used in your application,
+   *  please use KARGBApplication(new object name) or
+   *  KARGBApplication(new object name, allow_styles) instead of KApplication(...).
+   *
    * @param allowStyles Set to false to disable the loading on plugin based
    * styles. This is only useful to applications that do not display a GUI
    * normally. If you do create an application with @p allowStyles set to false
@@ -860,15 +866,88 @@ public:
    */
   TQString checkRecoverFile( const TQString& pFilename, bool& bRecover ) const;
 
-#ifdef Q_WS_X11
+#if defined(Q_WS_X11) && defined(COMPOSITE)
   /**
+   * @internal
    * Get the X11 display
    * @return the X11 Display
    */
-  Display *getDisplay() { return display; }
+   Display *getDisplay() { return display; }
+
+  /**
+   * @internal
+   * Gets X11 composition information
+   */
+   void getX11RGBAInformation(Display *dpy);
+
+  /**
+   * Gets the availability of a composition manager such as kompmgr
+   * Note that at least one application must have called detectCompositionManagerAvailable
+   * while the current X display was active in order for this method to return valid results.
+   * @see detectCompositionManagerAvailable()
+   * @return whether the composition manager is enabled
+   */
+   static bool isCompositionManagerAvailable();
+
+  /**
+   * Detects the availability of a composition manager such as kompmgr
+   * Note that calling this method will probably cause the screen to flicker.
+   * @see isCompositionManagerAvailable()
+   * @param force_available If set, force TDE to assume a composition manager is available
+   * @return whether the composition manager is enabled
+   */
+   bool detectCompositionManagerAvailable(bool force_available=false);
+
+  /**
+   * @internal
+   * Opens an X11 display and returns the handle to it
+   * @return the X11 display handle
+   */
+   Display *openX11RGBADisplay();
 #endif
 
   /**
+   * @internal
+   * Creates a default KApplication with transparency support
+   * (if available)
+   */
+   static KApplication KARGBApplicationObject( bool allowStyles=true );
+
+   #define KARGBApplication(objectname, ...) const KApplication &__kapplication_internal_app = KApplication::KARGBApplicationObject(__VA_ARGS__); KApplication &objectname = const_cast<KApplication&>(__kapplication_internal_app);
+
+  /**
+   * Returns the X11 display visual
+   *
+   * @return A pointer to the X11 display visual
+   */
+   Qt::HANDLE getX11RGBAVisual(Display *dpy);
+
+  /**
+   * Returns the X11 display colormap
+   *
+   * @return An X11 display colormap object
+   */
+   Qt::HANDLE getX11RGBAColormap(Display *dpy);
+
+  /**
+   * Returns whether or not X11 composition is available
+   * 
+   * You must first call getX11RGBAInformation()
+   * 
+   * Note that getX11RGBAInformation() has already
+   * been called if you used the default KApplication
+   * constructor.
+   *
+   * Additionally, at least one application must have called
+   * detectCompositionManagerAvailable while the current X 
+   * display was active in order for this method to return
+   * valid results.
+   *
+   * @return true if composition is available
+   */
+   bool isX11CompositionAvailable();
+
+  /**
    * Enables style plugins.
    *
    * This is useful only to applications that normally
@@ -1201,6 +1280,12 @@ private:
   void dcopClientPostInit();
   void initUrlActionRestrictions();
 
+  bool argb_visual;
+#if defined(Q_WS_X11) && defined(COMPOSITE)
+  Qt::HANDLE argb_x11_visual;
+  Qt::HANDLE argb_x11_colormap;
+#endif
+
 public:
   /**
    * @internal