--- src/neg.c	2006-11-26 09:49:23.000000000 -0600
+++ src/reg.c	2006-11-27 16:26:01.000000000 -0600
@@ -40,6 +40,12 @@
 
 /* defaults */
 
+static char *excludeWinType[] = {
+	N_("Desktop")
+};
+
+#define N_EXCLUDE_WIN_TYPE (sizeof (excludeWinType) / sizeof (excludeWinType[0]))
+
 #define NEG_TOGGLE_KEY_DEFAULT              "n"
 #define NEG_TOGGLE_MODIFIERS_DEFAULT        CompSuperMask
 
@@ -50,6 +56,13 @@
 #define NEG_DISPLAY_OPTION_SCREEN_TOGGLE     1
 #define NEG_DISPLAY_OPTION_NUM               2
 
+#define NEG_SCREEN_OPTION_EXCLUDE_NULL_WM_CLASS 0
+#define NEG_SCREEN_OPTION_EXCLUDE_WINDOW_TYPE	1
+#define NEG_SCREEN_OPTION_EXCLUDE_LIST			2
+#define NEG_SCREEN_OPTION_NUM                   3
+
+#define NEG_EXCLUDE_NULL_WM_CLASS_DEFAULT       TRUE
+
 static int displayPrivateIndex;
 
 typedef struct _NEGDisplay
@@ -62,10 +75,12 @@
 typedef struct _NEGSCreen
 {
     int windowPrivateIndex;
+    CompOption opt[NEG_SCREEN_OPTION_NUM];      /* array of screen options */
     DrawWindowTextureProc drawWindowTexture;    /* function pointer     */
     DamageWindowRectProc damageWindowRect;      /* function pointer     */
     PaintWindowProc paintWindow;        /* function pointer     */
     Bool isNeg;                 /* negative screen flag */
+	unsigned int excludeWMask;
 } NEGScreen;
 
 typedef struct _NEGWindow
@@ -85,10 +100,30 @@
 static void
 NEGToggle (CompWindow * w)
 {
+    CompOption *o;
+    int i;
+
+    NEG_SCREEN (w->screen);
     NEG_WINDOW (w);
 
     /* toggle window negative flag */
-    nw->isNeg = !nw->isNeg;
+	if (ns->opt[NEG_SCREEN_OPTION_EXCLUDE_NULL_WM_CLASS].value.b &&
+		(w->resClass == NULL))
+		nw->isNeg = FALSE;
+	else
+	{
+		if (!(ns->excludeWMask & w->type))
+			nw->isNeg = !nw->isNeg;
+	}
+
+    /* check exclude list */
+    o = &ns->opt[NEG_SCREEN_OPTION_EXCLUDE_LIST];
+    for (i = 0; i < o->value.list.nValue; i++)
+    {
+		if (w->resClass
+            && (strcmp (o->value.list.value[i].s, w->resClass) == 0))
+            nw->isNeg = FALSE;
+    }
 
     /* cause repainting */
     addWindowDamage (w);
@@ -610,6 +645,99 @@
     free (nd);
 }
 
+static void
+NEGScreenInitOptions (NEGScreen * ns)
+{
+    CompOption *o;
+	int i;
+
+	o = &ns->opt[NEG_SCREEN_OPTION_EXCLUDE_NULL_WM_CLASS];
+	o->name = "exclude_null_wm_class";
+	o->shortDesc = N_("Exclude Null WM_CLASS");
+	o->longDesc = N_("Exclude to negate if WM_CLASS is Null");
+	o->type = CompOptionTypeBool;
+	o->value.b = NEG_EXCLUDE_NULL_WM_CLASS_DEFAULT;
+
+	o = &ns->opt[NEG_SCREEN_OPTION_EXCLUDE_WINDOW_TYPE];
+	o->name = "exclude_window_types";
+	o->shortDesc = N_("Exclude Window Types");
+	o->longDesc = N_("Window types that should exclude to negate");
+	o->type = CompOptionTypeList;
+	o->value.list.type = CompOptionTypeString;
+	o->value.list.nValue = N_EXCLUDE_WIN_TYPE;
+	o->value.list.value =
+				malloc (sizeof (CompOptionValue) * N_EXCLUDE_WIN_TYPE);
+	for (i = 0; i < N_EXCLUDE_WIN_TYPE; i++)
+		o->value.list.value[i].s = strdup (excludeWinType[i]);
+	o->rest.s.string = (char **)windowTypeString;
+	o->rest.s.nString = nWindowTypeString;
+
+	ns->excludeWMask = compWindowTypeMaskFromStringList (&o->value);
+
+    o = &ns->opt[NEG_SCREEN_OPTION_EXCLUDE_LIST];
+    o->name = "exclude_list";
+    o->shortDesc = N_("WM_CLASS to exclude");
+    o->longDesc = N_("Windows classes to exclude from negating");
+    o->type = CompOptionTypeList;
+    o->value.list.type = CompOptionTypeString;
+    o->value.list.nValue = 0;
+    o->value.list.value = 0;
+    o->rest.s.string = 0;
+    o->rest.s.nString = 0;
+}
+
+static CompOption *
+NEGGetScreenOptions (CompScreen * screen, int *count)
+{
+    if (screen)
+    {
+        NEG_SCREEN (screen);
+        *count = NUM_OPTIONS (ns);
+        return ns->opt;
+    }
+    else
+    {
+        NEGScreen *ns = malloc (sizeof (NEGScreen));
+        NEGScreenInitOptions (ns);
+        *count = NUM_OPTIONS (ns);
+        return ns->opt;
+    }
+}
+
+static Bool
+NEGSetScreenOption (CompScreen * screen, char *name, CompOptionValue * value)
+{
+    CompOption *o;
+    int index;
+
+    NEG_SCREEN (screen);
+
+    o = compFindOption (ns->opt, NUM_OPTIONS (ns), name, &index);
+    if (!o)
+        return FALSE;
+
+    switch (index)
+    {
+	case NEG_SCREEN_OPTION_EXCLUDE_WINDOW_TYPE:
+		if (compSetOptionList (o, value))
+		{
+			ns->excludeWMask = compWindowTypeMaskFromStringList (&o->value);
+			return TRUE;
+		}
+		break;
+
+    case NEG_SCREEN_OPTION_EXCLUDE_LIST:
+        if (compSetOptionList (o, value))
+            return TRUE;
+        break;
+
+    default:
+        break;
+    }
+
+    return FALSE;
+}
+
 static Bool
 NEGInitScreen (CompPlugin * p, CompScreen * s)
 {
@@ -632,6 +760,9 @@
      */
     ns->isNeg = FALSE;
 
+	/* Initialize the screen options */
+	NEGScreenInitOptions (ns);
+
     /* add screen actions */
     addScreenAction (s,
                      &nd->opt[NEG_DISPLAY_OPTION_WINDOW_TOGGLE].value.action);
@@ -721,8 +852,8 @@
     NEGFiniWindow,
     NEGGetDisplayOptions,
     NEGSetDisplayOption,
-    0,                          /* GetScreenOptions */
-    0,                          /* SetScreenOption */
+    NEGGetScreenOptions,
+    NEGSetScreenOption,
     NULL,
     0,
     0,