Encapsulate colormap related functionality in own class

Split out the default and installed colormap from Workspace and put them
into an own class Colormaps.

The method updateColormaps is replaced by a slot update in Colormaps and
activeClientChanged signal is connected to this slot.

At the same time the colormap related code is straight forward ported to
xcb.

REVIEW: 110248

activation.cpp

@@ -264,7 +264,6 @@ void Workspace::setActiveClient(Client* c)
     updateStackingOrder(); // e.g. fullscreens have different layer when active/not-active
 
     rootInfo()->setActiveWindow(active_client ? active_client->window() : 0);
-    updateColormap();
 
     emit clientActivated(active_client);
     --set_active_client_recursion;

workspace.cpp

@@ -79,6 +79,31 @@ namespace KWin
 extern int screen_number;
 extern bool is_multihead;
 
+ColorMapper::ColorMapper(QObject *parent)
+    : QObject(parent)
+    , m_default(defaultScreen()->default_colormap)
+    , m_installed(defaultScreen()->default_colormap)
+{
+}
+
+ColorMapper::~ColorMapper()
+{
+}
+
+void ColorMapper::update()
+{
+    xcb_colormap_t cmap = m_default;
+    if (Client *c = Workspace::self()->activeClient()) {
+        if (c->colormap() != XCB_COLORMAP_NONE) {
+            cmap = c->colormap();
+        }
+    }
+    if (cmap != m_installed) {
+        xcb_install_colormap(connection(), cmap);
+        m_installed = cmap;
+    }
+}
+
 Workspace* Workspace::_self = 0;
 
 Workspace::Workspace(bool restore)
@@ -144,8 +169,8 @@ Workspace::Workspace(bool restore)
     options->loadConfig();
     options->loadCompositingConfig(false);
     DecorationPlugin::create(this);
-    default_colormap = DefaultColormap(display(), screen_number);
-    installed_colormap = default_colormap;
+    ColorMapper *colormaps = new ColorMapper(this);
+    connect(this, SIGNAL(clientActivated(KWin::Client*)), colormaps, SLOT(update()));
 
     updateXTime(); // Needed for proper initialization of user_time in Client ctor
 
@@ -716,20 +741,6 @@ void Workspace::slotUpdateToolWindows()
     updateToolWindows(true);
 }
 
-/**
- * Updates the current colormap according to the currently active client
- */
-void Workspace::updateColormap()
-{
-    Colormap cmap = default_colormap;
-    if (activeClient() && activeClient()->colormap() != None)
-        cmap = activeClient()->colormap();
-    if (cmap != installed_colormap) {
-        XInstallColormap(display(), cmap);
-        installed_colormap = cmap;
-    }
-}
-
 void Workspace::slotReloadConfig()
 {
     reconfigure();

workspace.h

@@ -116,8 +116,6 @@ public:
         return block_focus == 0;
     }
 
-    void updateColormap();
-
     /**
      * Indicates that the client c is being moved around by the user.
      */
@@ -530,10 +528,6 @@ private:
     bool global_shortcuts_disabled;
     bool global_shortcuts_disabled_for_client;
 
-    // Colormap handling
-    Colormap default_colormap;
-    Colormap installed_colormap;
-
     // Timer to collect requests for 'reconfigure'
     QTimer reconfigureTimer;
 
@@ -585,6 +579,19 @@ private:
     Workspace* ws;
 };
 
+class ColorMapper : public QObject
+{
+    Q_OBJECT
+public:
+    ColorMapper(QObject *parent);
+    virtual ~ColorMapper();
+public Q_SLOTS:
+    void update();
+private:
+    xcb_colormap_t m_default;
+    xcb_colormap_t m_installed;
+};
+
 //---------------------------------------------------------
 // Unsorted