Could This Patch Be Adapted For ROX?

Index: libxfce4panel/xfce-panel-external-item.c
===================================================================
--- libxfce4panel/xfce-panel-external-item.c	(revision 24752)
+++ libxfce4panel/xfce-panel-external-item.c	(working copy)
@@ -133,6 +133,12 @@
     iface->configure           = xfce_external_panel_item_configure;
 }
 
+static gboolean
+xfce_external_panel_item_expose(GtkWidget *widget, GdkEventExpose *event)
+{
+    return GTK_WIDGET_CLASS(xfce_external_panel_item_parent_class)->expose_event(widget, event);
+}
+
 static void
 xfce_external_panel_item_class_init (XfceExternalPanelItemClass * klass)
 {
@@ -146,6 +152,8 @@
 
     object_class->finalize = xfce_external_panel_item_finalize;
 
+    widget_class->expose_event = xfce_external_panel_item_expose;
+
     widget_class->button_press_event = 
         xfce_external_panel_item_button_press_event;
 }
@@ -166,6 +174,8 @@
     priv->to_be_removed   = FALSE;
     priv->restart         = FALSE;
     priv->file            = NULL;
+
+    gtk_widget_set_app_paintable(GTK_WIDGET(item), TRUE);
 }
 
 /* GObject */
Index: libxfce4panel/xfce-panel-external-plugin.c
===================================================================
--- libxfce4panel/xfce-panel-external-plugin.c	(revision 24752)
+++ libxfce4panel/xfce-panel-external-plugin.c	(working copy)
@@ -36,6 +36,8 @@
 #include "xfce-panel-external-plugin.h"
 #include "xfce-panel-plugin-messages.h"
 
+#define ALPHA                   0.2
+
 #define XFCE_EXTERNAL_PANEL_PLUGIN_GET_PRIVATE(o) \
     (G_TYPE_INSTANCE_GET_PRIVATE ((o), XFCE_TYPE_EXTERNAL_PANEL_PLUGIN, \
                                   XfceExternalPanelPluginPrivate))
@@ -174,18 +176,52 @@
     iface->set_panel_hidden = xfce_external_panel_plugin_set_panel_hidden;
 }
 
+static gboolean
+xfce_external_panel_plugin_expose(GtkWidget *widget, GdkEventExpose *event)
+{
+    cairo_t  *cr;
+    GtkStyle *style;
+    double    r,g,b;
+
+    cr = gdk_cairo_create (widget->window);	
+
+    cairo_rectangle (cr, event->area.x,
+                     event->area.y,
+                     event->area.width,
+                     event->area.height);
+    cairo_clip (cr);
+
+    cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+
+    /* fully transparent */
+    style = gtk_widget_get_style (widget);
+    r = (double) style->bg[widget->state].red / (double) 65535;
+    g = (double) style->bg[widget->state].green / (double) 65535;
+    b = (double) style->bg[widget->state].blue / (double) 65535;
+    cairo_set_source_rgba (cr, r, g, b, ALPHA);
+    cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+    cairo_paint (cr);
+		
+    cairo_destroy (cr);
+
+    return GTK_WIDGET_CLASS(xfce_external_panel_plugin_parent_class)->expose_event(widget, event);
+}
+
 static void
 xfce_external_panel_plugin_class_init (XfceExternalPanelPluginClass * klass)
 {
     GObjectClass *object_class;
+    GtkWidgetClass *widget_class;
 
     g_type_class_add_private (klass, sizeof (XfceExternalPanelPluginPrivate));
 
     object_class = (GObjectClass *) klass;
+    widget_class = (GtkWidgetClass *) klass;
 
     object_class->finalize     = xfce_external_panel_plugin_finalize;
     object_class->get_property = xfce_external_panel_plugin_get_property;
     object_class->set_property = xfce_external_panel_plugin_set_property;
+    widget_class->expose_event = xfce_external_panel_plugin_expose;
 
     /* properties */
 
@@ -219,6 +255,27 @@
     priv->construct       = NULL;
     priv->socket_id       = 0;
     priv->expand          = FALSE;
+
+    {
+	GtkWidget *widget;
+	GdkScreen    *screen;
+	GdkColormap  *colormap;
+
+	widget = GTK_WIDGET (plugin);
+
+	gtk_widget_set_app_paintable(widget, TRUE);
+
+	screen = gtk_widget_get_screen (widget);
+	colormap = gdk_screen_get_rgba_colormap (screen);
+
+	if (!colormap)
+	{
+		colormap = gdk_screen_get_rgb_colormap (screen);
+		g_debug (" No Alpha support \n");
+	}
+
+	gtk_widget_set_colormap (widget, colormap);
+    }
 }
 
 /* GObject */
Index: libxfce4panel/xfce-panel-window.c
===================================================================
--- libxfce4panel/xfce-panel-window.c	(revision 24752)
+++ libxfce4panel/xfce-panel-window.c	(working copy)
@@ -36,9 +36,10 @@
     (G_TYPE_INSTANCE_GET_PRIVATE ((o), XFCE_TYPE_PANEL_WINDOW, \
                                   XfcePanelWindowPrivate))
 
-#define DEFAULT_ORIENTATION   GTK_ORIENTATION_HORIZONTAL
-#define DEFAULT_HANDLE_STYLE  XFCE_HANDLE_STYLE_BOTH
-#define HANDLE_WIDTH  8
+#define DEFAULT_ORIENTATION     GTK_ORIENTATION_HORIZONTAL
+#define DEFAULT_HANDLE_STYLE    XFCE_HANDLE_STYLE_BOTH
+#define HANDLE_WIDTH            8
+#define ALPHA                   0.2
 
 enum
 {
@@ -353,6 +354,26 @@
     priv->right_border      = TRUE;
     priv->movable          = TRUE;
 
+    {
+	GtkWidget *widget;
+	GdkScreen    *screen;
+	GdkColormap  *colormap;
+
+	widget = GTK_WIDGET (panel_window);
+
+	gtk_widget_set_app_paintable(widget, TRUE);
+
+	screen = gtk_widget_get_screen (widget);
+	colormap = gdk_screen_get_rgba_colormap (screen);
+
+	if (!colormap)
+	{
+		colormap = gdk_screen_get_rgb_colormap (screen);
+		g_debug (" No Alpha support \n");
+	}
+
+	gtk_widget_set_colormap (widget, colormap);
+    }
     gtk_widget_set_events (GTK_WIDGET (panel_window),
                            gtk_widget_get_events (GTK_WIDGET (panel_window))
                            | GDK_BUTTON_MOTION_MASK
@@ -462,20 +483,31 @@
 
 /* drawing, size and style */
 static void
-_panel_window_paint_border (XfcePanelWindow * panel)
+_panel_window_paint_border (XfcePanelWindow * panel, cairo_t *cr)
 {
-    XfcePanelWindowPrivate *priv = XFCE_PANEL_WINDOW_GET_PRIVATE (panel);
-    GdkWindow *window = GTK_WIDGET (panel)->window;
-    GtkAllocation *a = &(GTK_WIDGET (panel)->allocation);
-    GtkStyle *style = GTK_WIDGET (panel)->style;
-    GtkStateType state_type = GTK_WIDGET_STATE (GTK_WIDGET (panel));
-    int top, bottom, left, right;
+    XfcePanelWindowPrivate *priv       = XFCE_PANEL_WINDOW_GET_PRIVATE (panel);
+//    GdkWindow              *window     = GTK_WIDGET (panel)->window;
+    GtkAllocation          *a          = &(GTK_WIDGET (panel)->allocation);
+    GtkStyle               *style      = GTK_WIDGET (panel)->style;
+//    GtkStateType            state_type = GTK_WIDGET_STATE (GTK_WIDGET (panel));
+    int                     top, bottom, left, right;
+    double                  r, g, b;
+    GtkWidget              *widget     = GTK_WIDGET (panel);
 
-    top    = priv->top_border    ? style->ythickness : 0;
-    bottom = priv->bottom_border ? style->ythickness : 0;
-    left   = priv->left_border   ? style->xthickness : 0;
-    right  = priv->right_border  ? style->xthickness : 0;
-    
+    top    = priv->top_border    ? 1 /*style->ythickness*/ : 0;
+    bottom = priv->bottom_border ? 1 /*style->ythickness*/ : 0;
+    left   = priv->left_border   ? 1 /*style->xthickness*/ : 0;
+    right  = priv->right_border  ? 1 /*style->xthickness*/ : 0;
+
+    cairo_set_line_width (cr, /* top > 1 ? 2.0 :*/ 1.0);
+    cairo_rectangle (cr, a->x, a->y, a->width, a->height);
+
+    r = (double) style->dark[widget->state].red / (double) 65535;
+    g = (double) style->dark[widget->state].green / (double) 65535;
+    b = (double) style->dark[widget->state].blue / (double) 65535;
+    cairo_set_source_rgba (cr, r, g, b, ALPHA);
+    cairo_stroke (cr);
+#if 0    
     /* Code based on gtk-xfce-engine-2 */
 
     /* Attempt to explain the code below with some ASCII 'art'
@@ -615,17 +647,40 @@
                            x1, y1, x1, y2);
         }
     }
+#endif
 }
 
 static gint
 xfce_panel_window_expose (GtkWidget * widget, GdkEventExpose * event)
 {
-    XfcePanelWindow *panel_window = XFCE_PANEL_WINDOW (widget);
+    cairo_t                *cr;
+    GtkStyle               *style;
+    double                  r,g,b;
+    XfcePanelWindow        *panel_window = XFCE_PANEL_WINDOW (widget);
     XfcePanelWindowPrivate *priv =
         XFCE_PANEL_WINDOW_GET_PRIVATE (panel_window);
 
     if (GTK_WIDGET_DRAWABLE (widget))
     {
+        cr = gdk_cairo_create (widget->window);	
+
+        cairo_rectangle (cr, event->area.x,
+                         event->area.y,
+                         event->area.width,
+                         event->area.height);
+        cairo_clip (cr);
+
+        cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+
+        /* fully transparent */
+        style = gtk_widget_get_style (widget);
+        r = (double) style->bg[widget->state].red / (double) 65535;
+        g = (double) style->bg[widget->state].green / (double) 65535;
+        b = (double) style->bg[widget->state].blue / (double) 65535;
+        cairo_set_source_rgba (cr, r, g, b, ALPHA);
+        cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+        cairo_paint (cr);
+
         if (GTK_BIN (widget)->child)
         {
             gtk_container_propagate_expose (GTK_CONTAINER (widget),
@@ -648,7 +703,9 @@
                 break;
         }
     
-        _panel_window_paint_border (panel_window);
+        _panel_window_paint_border (panel_window, cr);
+
+        cairo_destroy (cr);
     }
 
     return FALSE;
@@ -671,21 +728,21 @@
     }
     
     if (priv->top_border)
-        requisition->height += widget->style->ythickness;
+        requisition->height += 1; //widget->style->ythickness;
     if (priv->bottom_border)
-        requisition->height += widget->style->ythickness;
+        requisition->height += 1; //widget->style->ythickness;
     if (priv->left_border)
-        requisition->width += widget->style->xthickness;
+        requisition->width += 1; //widget->style->xthickness;
     if (priv->right_border)
-        requisition->width += widget->style->xthickness;
+        requisition->width += 1; //widget->style->xthickness;
 
     if (GTK_ORIENTATION_HORIZONTAL == priv->orientation)
     {
-        thick = 2 * widget->style->xthickness;
+        thick = 2; // * widget->style->xthickness;
     }
     else
     {
-        thick = 2 * widget->style->ythickness;
+        thick = 2; // * widget->style->ythickness;
     }
 
     switch (priv->handle_style)
@@ -749,9 +806,9 @@
         int start_handle_size, end_handle_size, thick;
 
         if (GTK_ORIENTATION_HORIZONTAL == priv->orientation)
-            thick = 2 * widget->style->xthickness;
+            thick = 2; // * widget->style->xthickness;
         else
-            thick = 2 * widget->style->ythickness;
+            thick = 2; // * widget->style->ythickness;
 
         start_handle_size = end_handle_size = 0;
 
@@ -774,21 +831,21 @@
 
         if (priv->top_border)
         {
-            childalloc.y += widget->style->ythickness;
-            childalloc.height -= widget->style->ythickness;
+            childalloc.y += 1; //widget->style->ythickness;
+            childalloc.height -= 1; //widget->style->ythickness;
         }
         
         if (priv->bottom_border)
-            childalloc.height -= widget->style->ythickness;
+            childalloc.height -= 1; //widget->style->ythickness;
         
         if (priv->left_border)
         {
-            childalloc.x += widget->style->xthickness;
-            childalloc.width -= widget->style->xthickness;
+            childalloc.x += 1; //widget->style->xthickness;
+            childalloc.width -= 1; //widget->style->xthickness;
         }
         
         if (priv->right_border)
-            childalloc.width -= widget->style->xthickness;
+            childalloc.width -= 1; //widget->style->xthickness;
             
         if (priv->orientation == GTK_ORIENTATION_HORIZONTAL)
         {
@@ -922,8 +979,8 @@
     int x, y, w, h, xthick, ythick;
     gboolean horizontal = priv->orientation == GTK_ORIENTATION_HORIZONTAL;
 
-    xthick = widget->style->xthickness;
-    ythick = widget->style->ythickness;
+    xthick = 1; //widget->style->xthickness;
+    ythick = 1; //widget->style->ythickness;
 
     if (horizontal)
     {
Index: libxfce4panel/xfce-panel-internal-plugin.c
===================================================================
--- libxfce4panel/xfce-panel-internal-plugin.c	(revision 24752)
+++ libxfce4panel/xfce-panel-internal-plugin.c	(working copy)
@@ -33,6 +33,8 @@
 #include "xfce-panel-plugin-iface-private.h"
 #include "xfce-panel-plugin-iface.h"
 
+#define ALPHA                   0.2
+
 #define XFCE_INTERNAL_PANEL_PLUGIN_GET_PRIVATE(o) \
     (G_TYPE_INSTANCE_GET_PRIVATE ((o), XFCE_TYPE_INTERNAL_PANEL_PLUGIN, \
                                   XfceInternalPanelPluginPrivate))
@@ -200,10 +202,39 @@
     iface->focus_panel      = xfce_internal_panel_plugin_focus_panel;
 }
 
+static gboolean
+xfce_internal_panel_plugin_expose(GtkWidget *widget, GdkEventExpose *event)
+{
+    cairo_t  *cr;
+    GtkStyle *style;
+    double   r,g,b;
+
+    cr = gdk_cairo_create (widget->window);	
+
+    cairo_rectangle (cr, event->area.x,
+                     event->area.y,
+                     event->area.width,
+                     event->area.height);
+    cairo_clip (cr);
+
+    style = gtk_widget_get_style (widget);
+    r = (double) style->bg[widget->state].red / (double) 65535;
+    g = (double) style->bg[widget->state].green / (double) 65535;
+    b = (double) style->bg[widget->state].blue / (double) 65535;
+    cairo_set_source_rgba (cr, r, g, b, ALPHA);
+    cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+    cairo_paint (cr);
+		
+    cairo_destroy (cr);
+
+    return GTK_WIDGET_CLASS(xfce_internal_panel_plugin_parent_class)->expose_event(widget, event);
+}
+
 static void
 xfce_internal_panel_plugin_class_init (XfceInternalPanelPluginClass * klass)
 {
     GObjectClass *object_class;
+    GtkWidgetClass *widget_class;
 
     g_type_class_add_private (klass, sizeof (XfceInternalPanelPluginPrivate));
 
@@ -213,6 +244,10 @@
     object_class->get_property = xfce_internal_panel_plugin_get_property;
     object_class->set_property = xfce_internal_panel_plugin_set_property;
 
+    widget_class = (GtkWidgetClass *) klass;
+
+    widget_class->expose_event = xfce_internal_panel_plugin_expose;
+
     /* properties */
 
     g_object_class_override_property (object_class, PROP_NAME, "name");
@@ -243,6 +278,8 @@
     priv->size            = 0;
     priv->screen_position = XFCE_SCREEN_POSITION_NONE;
     priv->expand          = FALSE;
+
+    gtk_widget_set_app_paintable(GTK_WIDGET(plugin), TRUE);
 }
 
 /* GObject */
Index: plugins/separator/separator.c
===================================================================
--- plugins/separator/separator.c	(revision 24752)
+++ plugins/separator/separator.c	(working copy)
@@ -31,8 +31,9 @@
 #include <libxfce4panel/xfce-panel-plugin.h>
 
 #define SEPARATOR_WIDTH  10
-#define SEP_START        0.15
-#define SEP_END          0.85
+#define SEP_START        0.0
+#define SEP_END          1.0
+#define ALPHA            0.2
 
 static void separator_properties_dialog (XfcePanelPlugin *plugin);
 
@@ -56,32 +57,65 @@
     if (GTK_WIDGET_DRAWABLE (widget))
     {
         GtkAllocation *allocation = &(widget->allocation);
-        int start, end, position;
+        int            start, end, position;
+        cairo_t       *cr;
+        GtkStyle      *style;
+        double         r,g,b;
 
+        style = gtk_widget_get_style (widget);
+        cr = gdk_cairo_create (widget->window);
+        cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
+
+        cairo_rectangle (cr, event->area.x,
+                         event->area.y,
+                         event->area.width,
+                         event->area.height);
+        cairo_clip (cr);
+
+        r = (double) style->bg[widget->state].red / (double) 65535;
+        g = (double) style->bg[widget->state].green / (double) 65535;
+        b = (double) style->bg[widget->state].blue / (double) 65535;
+        cairo_set_source_rgba (cr, r, g, b, ALPHA);
+        cairo_paint (cr);
+
+        r = (double) style->dark[widget->state].red / (double) 65535;
+        g = (double) style->dark[widget->state].green / (double) 65535;
+        b = (double) style->dark[widget->state].blue / (double) 65535;
+        cairo_set_source_rgba (cr, r, g, b, 1.0 - ((1.0 - ALPHA) / 3));
+
         if (xfce_panel_plugin_get_orientation (plugin) ==
                 GTK_ORIENTATION_HORIZONTAL)
         {
             start = allocation->y + SEP_START * allocation->height;
             end = allocation->y + SEP_END * allocation->height;
             position = allocation->x + allocation->width / 2;
-        
-            gtk_paint_vline (widget->style, widget->window,
+  
+            cairo_move_to (cr, position, start);
+            cairo_line_to (cr, position, end);
+
+/*            gtk_paint_vline (widget->style, widget->window,
                              GTK_STATE_NORMAL,
                              &(event->area), widget, "separator",
                              start, end, position);
-        }
+*/        }
         else
         {
             start = allocation->x + SEP_START * allocation->width;
             end = allocation->x + SEP_END * allocation->width;
             position = allocation->y + allocation->height / 2;
         
-            gtk_paint_hline (widget->style, widget->window, 
+            cairo_move_to (cr, start, position);
+            cairo_line_to (cr, end, position);
+
+/*            gtk_paint_hline (widget->style, widget->window, 
                              GTK_STATE_NORMAL,
                              &(event->area), widget, "separator",
                              start, end, position);
-        }
+*/        }
 
+        cairo_stroke (cr);
+        cairo_destroy (cr);
+
         return TRUE;
     }
 
@@ -91,12 +125,28 @@
 static void
 separator_add_widget (XfcePanelPlugin *plugin)
 {
-    GtkWidget *widget;
+    GtkWidget   *widget;
+    GdkScreen   *screen;
+    GdkColormap *colormap;
     
     widget = gtk_drawing_area_new ();
+
+    gtk_widget_set_app_paintable(widget, TRUE);
+
+    screen = gtk_widget_get_screen (widget);
+    colormap = gdk_screen_get_rgba_colormap (screen);
+
+    if (!colormap)
+    {
+        colormap = gdk_screen_get_rgb_colormap (screen);
+        g_debug (" No Alpha support \n");
+    }
+
+    gtk_widget_set_colormap (widget, colormap);
+
     gtk_widget_show (widget);
     gtk_container_add (GTK_CONTAINER (plugin), widget);
-    
+
     g_signal_connect (widget, "expose-event", 
                       G_CALLBACK (separator_expose), plugin);
 }