Add new cycling option

When using Xinerama, make it possible only to cycle between those
windows that are on the currently active head - AFAICT this means
windows that have the majority of their area on the same head as
the pointer.

Patch complete with WPrefs integration, alas this being quite
unusable - for a lack of a better idea, I tucked the option on the
expert panel, making the item list too tall - making it scrollable
would be a nice addition.

The default for the new option (CycleActiveHeadOnly) should be NO,
that is, no change in default behaviour.

WPrefs.app/Expert.c

@@ -32,7 +32,7 @@ typedef struct _Panel {
 
 	WMWidget *parent;
 
-	WMButton *swi[8];
+	WMButton *swi[9];
 
 } _Panel;
 
@@ -50,6 +50,7 @@ static void showData(_Panel * panel)
 	WMSetButtonSelected(panel->swi[5], GetBoolForKey("DisableBlinking"));
 	WMSetButtonSelected(panel->swi[6], GetBoolForKey("AntialiasedText"));
 	WMSetButtonSelected(panel->swi[7], GetBoolForKey("SingleClickLaunch"));
+	WMSetButtonSelected(panel->swi[8], GetBoolForKey("CycleActiveHeadOnly"));
 }
 
 static void createPanel(Panel * p)
@@ -60,12 +61,14 @@ static void createPanel(Panel * p)
 	panel->box = WMCreateBox(panel->parent);
 	WMSetViewExpandsToParent(WMWidgetView(panel->box), 2, 2, 2, 2);
 
-	for (i = 0; i < 8; i++) {
+	for (i = 0; i < 9; i++) {
 		panel->swi[i] = WMCreateSwitchButton(panel->box);
 		WMResizeWidget(panel->swi[i], FRAME_WIDTH - 40, 25);
 		WMMoveWidget(panel->swi[i], 20, 20 + i * 25);
 	}
 
+	/* XXX: it would be HIGHLY desireable if this could scroll vertically */
+
 	WMSetButtonText(panel->swi[0],
 			_("Disable miniwindows (icons for minimized windows). For use with KDE/GNOME."));
 	WMSetButtonText(panel->swi[1], _("Do not set non-WindowMaker specific parameters (do not use xset)."));
@@ -75,6 +78,7 @@ static void createPanel(Panel * p)
 	WMSetButtonText(panel->swi[5], _("Disable selection animation for selected icons."));
 	WMSetButtonText(panel->swi[6], _("Smooth font edges (needs restart)."));
 	WMSetButtonText(panel->swi[7], _("Launch applications and restore windows with a single click."));
+	WMSetButtonText(panel->swi[8], _("Cycle windows only on the active head."));
 
 	WMSetButtonEnabled(panel->swi[6], True);
 
@@ -98,6 +102,7 @@ static void storeDefaults(_Panel * panel)
 	SetBoolForKey(WMGetButtonSelected(panel->swi[5]), "DisableBlinking");
 	SetBoolForKey(WMGetButtonSelected(panel->swi[6]), "AntialiasedText");
 	SetBoolForKey(WMGetButtonSelected(panel->swi[7]), "SingleClickLaunch");
+	SetBoolForKey(WMGetButtonSelected(panel->swi[8]), "CycleActiveHeadOnly");
 }
 
 Panel *InitExpert(WMScreen * scr, WMWidget * parent)

src/WindowMaker.h

@@ -413,6 +413,7 @@ typedef struct WPreferences {
     char workspace_border_position;     /* Where to leave a workspace border */
     char single_click;                  /* single click to lauch applications */
     int history_lines;                  /* history of "Run..." dialog */
+    char cycle_active_head_only;        /* Cycle only windows on the active head */
 
     RImage *swtileImage;
     RImage *swbackImage[9];

src/defaults.c

@@ -655,7 +655,9 @@ WDefaultEntry optionList[] = {
 	{"SelectCursor", "(builtin, cross)", (void *)WCUR_SELECT,
 	 NULL, getCursor, setCursor},
 	{"DialogHistoryLines", "500", NULL,
-	 &wPreferences.history_lines, getInt, NULL}
+	 &wPreferences.history_lines, getInt, NULL},
+	{"CycleActiveHeadOnly", "NO", NULL,
+	 &wPreferences.cycle_active_head_only, getBool, NULL}
 };
 
 #if 0

src/switchpanel.c

@@ -80,6 +80,11 @@ static int canReceiveFocus(WWindow * wwin)
 {
 	if (wwin->frame->workspace != wwin->screen_ptr->current_workspace)
 		return 0;
+
+	if (wPreferences.cycle_active_head_only &&
+	    wGetHeadForWindow(wwin) != wGetHeadForPointerLocation(wwin->screen_ptr))
+		return 0;
+
 	if (!wwin->flags.mapped) {
 		if (!wwin->flags.shaded && !wwin->flags.miniaturized && !wwin->flags.hidden)
 			return 0;