UI: New Global Top-Bar (WIP)

== Main Features/Changes for Users

* Add horizontal bar at top of all non-temp windows, consisting out of two horizontal sub-bars.
* Upper sub-bar contains global menus (File, Render, etc.), tabs for workspaces and scene selector.
* Lower sub-bar contains object mode selector, screen-layout and render-layer selector. Later operator and/or tool settings will be placed here.
* Individual sections of the topbar are individually scrollable.
* Workspace tabs can be double- or ctrl-clicked for renaming and contain 'x' icon for deleting.
* Top-bar should scale nicely with DPI.
* The lower half of the top-bar can be hided by dragging the lower top-bar edge up. Better hiding options are planned (e.g. hide in fullscreen modes).
* Info editors at the top of the window and using the full window width with be replaced by the top-bar.
* In fullscreen modes, no more info editor is added on top, the top-bar replaces it.

== Technical Features/Changes

* Adds initial support for global areas

  A global area is part of the window, not part of the regular screen-layout.
  I've added a macro iterator to iterate over both, global and screen-layout level areas. When iterating over areas, from now on developers should always consider if they have to include global areas.
* Adds a TOPBAR editor type

  The editor type is hidden in the UI editor type menu.
* Adds a variation of the ID template to display IDs as tab buttons (template_ID_tabs in BPY)
* Does various changes to RNA button creation code to improve their appearance in the horizontal top-bar.
* Adds support for dynamically sized regions. That is, regions that scale automatically to the layout bounds.

  The code for this is currently a big hack (it's based on drawing the UI multiple times). This should definitely be improved.
* Adds a template for displaying operator properties optimized for the top-bar. This will probably change a lot still and is in fact disabled in code.

Since the final top-bar design depends a lot on other 2.8 designs (mainly tool-system and workspaces), we decided to not show the operator or tool settings in the top-bar for now. That means most of the lower sub-bar is empty for the time being.

NOTE: Top-bar or global area data is not written to files or SDNA. They are simply added to the window when opening Blender or reading a file. This allows us doing changes to the top-bar without having to care for compatibility.

== ToDo's

It's a bit hard to predict all the ToDo's here are the known main ones:
* Add options for the new active-tool system and for operator redo to the topbar.
* Automatically hide the top-bar in fullscreen modes.
* General visual polish.
* Top-bar drag & drop support (WIP in temp-tab_drag_drop).
* Improve dynamic regions (should also fix some layout glitches).
* Make internal terminology consistent.
* Enable topbar file writing once design is more advanced.
* Address TODO's and XXX's in code :)

Thanks @brecht for the review! And @sergey for the complaining ;)

Differential Revision: D2758

7 files changed, 126 insertions, 66 deletions

diff --git a/source/blender/windowmanager/WM_api.h b/source/blender/windowmanager/WM_api.h
index 7869973f1ec..652cdac6315 100644
--- a/source/blender/windowmanager/WM_api.h
+++ b/source/blender/windowmanager/WM_api.h
@@ -96,9 +96,11 @@ void		WM_init_splash		(struct bContext *C);
 
 void		WM_check			(struct bContext *C);
 
-int			WM_window_pixels_x		(struct wmWindow *win);
-int			WM_window_pixels_y		(struct wmWindow *win);
-bool		WM_window_is_fullscreen	(struct wmWindow *win);
+int WM_window_pixels_x(const struct wmWindow *win);
+int WM_window_pixels_y(const struct wmWindow *win);
+int WM_window_screen_pixels_x(const struct wmWindow *win);
+int WM_window_screen_pixels_y(const struct wmWindow *win);
+bool WM_window_is_fullscreen(struct wmWindow *win);
 
 void WM_windows_scene_data_sync(const ListBase *win_lb, struct Scene *scene) ATTR_NONNULL();
 struct Scene *WM_windows_scene_get_from_screen(const struct wmWindowManager *wm, const struct bScreen *screen) ATTR_NONNULL() ATTR_WARN_UNUSED_RESULT;
diff --git a/source/blender/windowmanager/WM_types.h b/source/blender/windowmanager/WM_types.h
index 4bd5bcfc056..59a3f703614 100644
--- a/source/blender/windowmanager/WM_types.h
+++ b/source/blender/windowmanager/WM_types.h
@@ -278,6 +278,7 @@ typedef struct wmNotifier {
 #define ND_LAYOUTSET		(7<<16)
 #define ND_SKETCH			(8<<16)
 #define ND_WORKSPACE_SET	(9<<16)
+#define ND_WORKSPACE_DELETE (10<<16)
 
 	/* NC_SCENE Scene */
 #define ND_SCENEBROWSE		(1<<16)
diff --git a/source/blender/windowmanager/intern/wm.c b/source/blender/windowmanager/intern/wm.c
index 27107299863..91e47b67130 100644
--- a/source/blender/windowmanager/intern/wm.c
+++ b/source/blender/windowmanager/intern/wm.c
@@ -165,6 +165,11 @@ void wm_operator_register(bContext *C, wmOperator *op)
 	wmWindowManager *wm = CTX_wm_manager(C);
 	int tot = 0;
 
+#ifdef WITH_REDO_REGION_REMOVAL
+	op->execution_area = CTX_wm_area(C);
+	op->execution_region = CTX_wm_region(C);
+#endif
+
 	BLI_addtail(&wm->operators, op);
 
 	/* only count registered operators */
@@ -465,7 +470,8 @@ void wm_add_default(Main *bmain, bContext *C)
 	WM_window_set_active_workspace(win, workspace);
 	WM_window_set_active_layout(win, workspace, layout);
 	screen->winid = win->winid;
-	
+	ED_screen_global_areas_create(win);
+
 	wm->winactive = win;
 	wm->file_saved = 1;
 	wm_window_make_drawable(wm, win);
diff --git a/source/blender/windowmanager/intern/wm_draw.c b/source/blender/windowmanager/intern/wm_draw.c
index c650bfe08c9..99319e009c8 100644
--- a/source/blender/windowmanager/intern/wm_draw.c
+++ b/source/blender/windowmanager/intern/wm_draw.c
@@ -162,6 +162,14 @@ static void wm_region_test_render_do_draw(const Scene *scene, struct Depsgraph *
 	}
 }
 
+static void wm_draw_region(bContext *C, ARegion *ar)
+{
+	CTX_wm_region_set(C, ar);
+	ED_region_do_draw(C, ar);
+	ar->do_draw = false;
+	CTX_wm_region_set(C, NULL);
+}
+
 /********************** draw all **************************/
 /* - reference method, draw all each time                 */
 
@@ -208,11 +216,10 @@ static void wm_draw_callbacks(wmWindow *win)
 static void wm_method_draw_full(bContext *C, wmWindow *win)
 {
 	bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 
 	/* draw area regions */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
@@ -254,12 +261,11 @@ static void wm_method_draw_full(bContext *C, wmWindow *win)
 /*   same buffer as we swapped to the front               */
 
 /* mark area-regions to redraw if overlapped with rect */
-static void wm_flush_regions_down(bScreen *screen, rcti *dirty)
+static void wm_flush_regions_down(wmWindow *win, bScreen *screen, rcti *dirty)
 {
-	ScrArea *sa;
 	ARegion *ar;
 
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
 			if (BLI_rcti_isect(dirty, &ar->winrct, NULL)) {
 				ar->do_draw = RGN_DRAW;
@@ -288,24 +294,25 @@ static void wm_method_draw_overlap_all(bContext *C, wmWindow *win, int exchange)
 {
 	wmWindowManager *wm = CTX_wm_manager(C);
 	bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 	static rcti rect = {0, 0, 0, 0};
 
 	/* after backbuffer selection draw, we need to redraw */
-	for (sa = screen->areabase.first; sa; sa = sa->next)
+	ED_screen_areas_iter(win, screen, sa) {
 		for (ar = sa->regionbase.first; ar; ar = ar->next)
 			if (ar->visible && !wm_area_test_invalid_backbuf(sa))
 				ED_region_tag_redraw(ar);
+	}
 
 	/* flush overlapping regions */
 	if (screen->regionbase.first) {
 		/* flush redraws of area regions up to overlapping regions */
-		for (sa = screen->areabase.first; sa; sa = sa->next)
+		ED_screen_areas_iter(win, screen, sa) {
 			for (ar = sa->regionbase.first; ar; ar = ar->next)
 				if (ar->visible && ar->do_draw)
 					wm_flush_regions_up(screen, &ar->winrct);
-		
+		}
+
 		/* flush between overlapping regions */
 		for (ar = screen->regionbase.last; ar; ar = ar->prev)
 			if (ar->visible && ar->do_draw)
@@ -314,12 +321,12 @@ static void wm_method_draw_overlap_all(bContext *C, wmWindow *win, int exchange)
 		/* flush redraws of overlapping regions down to area regions */
 		for (ar = screen->regionbase.last; ar; ar = ar->prev)
 			if (ar->visible && ar->do_draw)
-				wm_flush_regions_down(screen, &ar->winrct);
+				wm_flush_regions_down(win, screen, &ar->winrct);
 	}
 
 	/* flush drag item */
 	if (rect.xmin != rect.xmax) {
-		wm_flush_regions_down(screen, &rect);
+		wm_flush_regions_down(win, screen, &rect);
 		rect.xmin = rect.xmax = 0;
 	}
 	if (wm->drags.first) {
@@ -328,7 +335,7 @@ static void wm_method_draw_overlap_all(bContext *C, wmWindow *win, int exchange)
 	}
 	
 	/* draw marked area regions */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
@@ -526,7 +533,6 @@ static void wm_method_draw_triple(bContext *C, wmWindow *win)
 	wmWindowManager *wm = CTX_wm_manager(C);
 	wmDrawData *dd, *dd_next, *drawdata = win->drawdata.first;
 	bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 	bool copytex = false;
 
@@ -567,17 +573,14 @@ static void wm_method_draw_triple(bContext *C, wmWindow *win)
 
 	wmDrawTriple *triple = drawdata->triple;
 
-	/* draw marked area regions */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	/* draw marked area regions (also global ones) */
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
 			if (ar->visible && ar->do_draw) {
 				if (ar->overlap == false) {
-					CTX_wm_region_set(C, ar);
-					ED_region_do_draw(C, ar);
-					ar->do_draw = false;
-					CTX_wm_region_set(C, NULL);
+					wm_draw_region(C, ar);
 					copytex = true;
 				}
 			}
@@ -594,7 +597,7 @@ static void wm_method_draw_triple(bContext *C, wmWindow *win)
 	}
 
 	if (wm->paintcursors.first) {
-		for (sa = screen->areabase.first; sa; sa = sa->next) {
+		ED_screen_areas_iter(win, screen, sa) {
 			for (ar = sa->regionbase.first; ar; ar = ar->next) {
 				if (ar->visible && ar == screen->active_region) {
 					CTX_wm_area_set(C, sa);
@@ -614,16 +617,12 @@ static void wm_method_draw_triple(bContext *C, wmWindow *win)
 	}
 
 	/* draw overlapping area regions (always like popups) */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
 			if (ar->visible && ar->overlap) {
-				CTX_wm_region_set(C, ar);
-				ED_region_do_draw(C, ar);
-				ar->do_draw = false;
-				CTX_wm_region_set(C, NULL);
-
+				wm_draw_region(C, ar);
 				wm_draw_region_blend(win, ar, triple);
 			}
 		}
@@ -662,7 +661,6 @@ static void wm_method_draw_triple_multiview(bContext *C, wmWindow *win, eStereoV
 	wmDrawData *drawdata;
 	wmDrawTriple *triple_data, *triple_all;
 	bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 	int copytex = false;
 	int id;
@@ -703,7 +701,7 @@ static void wm_method_draw_triple_multiview(bContext *C, wmWindow *win, eStereoV
 	triple_all  = ((wmDrawData *) BLI_findlink(&win->drawdata, (sview * 2) + 1))->triple;
 
 	/* draw marked area regions */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		switch (sa->spacetype) {
@@ -769,7 +767,7 @@ static void wm_method_draw_triple_multiview(bContext *C, wmWindow *win, eStereoV
 	}
 
 	if (wm->paintcursors.first) {
-		for (sa = screen->areabase.first; sa; sa = sa->next) {
+		ED_screen_areas_iter(win, screen, sa) {
 			for (ar = sa->regionbase.first; ar; ar = ar->next) {
 				if (ar->visible && ar == screen->active_region) {
 					CTX_wm_area_set(C, sa);
@@ -789,7 +787,7 @@ static void wm_method_draw_triple_multiview(bContext *C, wmWindow *win, eStereoV
 	}
 
 	/* draw overlapping area regions (always like popups) */
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		CTX_wm_area_set(C, sa);
 
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
@@ -849,7 +847,6 @@ static bool wm_draw_update_test_window(wmWindow *win)
 	/*const*/ ViewLayer *view_layer = BKE_workspace_view_layer_get(workspace, scene);
 	struct Depsgraph *depsgraph = BKE_scene_get_depsgraph(scene, view_layer, true);
 	const bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 	bool do_draw = false;
 
@@ -862,7 +859,7 @@ static bool wm_draw_update_test_window(wmWindow *win)
 			do_draw = true;
 	}
 
-	for (sa = screen->areabase.first; sa; sa = sa->next) {
+	ED_screen_areas_iter(win, screen, sa) {
 		for (ar = sa->regionbase.first; ar; ar = ar->next) {
 			wm_region_test_render_do_draw(scene, depsgraph, sa, ar);
 
@@ -963,8 +960,7 @@ void wm_draw_update(bContext *C)
 			wm_window_make_drawable(wm, win);
 
 			/* notifiers for screen redraw */
-			if (screen->do_refresh)
-				ED_screen_refresh(wm, win);
+			ED_screen_ensure_updated(wm, win, screen);
 
 			int drawmethod = wm_automatic_draw_method(win);
 
@@ -1011,17 +1007,18 @@ void wm_draw_data_free(wmWindow *win)
 void wm_draw_window_clear(wmWindow *win)
 {
 	bScreen *screen = WM_window_get_active_screen(win);
-	ScrArea *sa;
 	ARegion *ar;
 
 	wm_draw_data_free(win);
 
 	/* clear screen swap flags */
 	if (screen) {
-		for (sa = screen->areabase.first; sa; sa = sa->next)
-			for (ar = sa->regionbase.first; ar; ar = ar->next)
+		ED_screen_areas_iter(win, screen, sa) {
+			for (ar = sa->regionbase.first; ar; ar = ar->next) {
 				ar->swap = WIN_NONE_OK;
-		
+			}
+		}
+
 		screen->swap = WIN_NONE_OK;
 	}
 }
@@ -1032,7 +1029,7 @@ void wm_draw_region_clear(wmWindow *win, ARegion *ar)
 	int drawmethod = wm_automatic_draw_method(win);
 
 	if (ELEM(drawmethod, USER_DRAW_OVERLAP, USER_DRAW_OVERLAP_FLIP))
-		wm_flush_regions_down(screen, &ar->winrct);
+		wm_flush_regions_down(win, screen, &ar->winrct);
 
 	screen->do_draw = true;
 }
diff --git a/source/blender/windowmanager/intern/wm_event_system.c b/source/blender/windowmanager/intern/wm_event_system.c
index 6ec68614116..218f48e9be6 100644
--- a/source/blender/windowmanager/intern/wm_event_system.c
+++ b/source/blender/windowmanager/intern/wm_event_system.c
@@ -386,6 +386,13 @@ void wm_event_do_notifiers(bContext *C)
 						if (G.debug & G_DEBUG_EVENTS)
 							printf("%s: Workspace set %p\n", __func__, note->reference);
 					}
+					else if (note->data == ND_WORKSPACE_DELETE) {
+						WorkSpace *workspace = note->reference;
+
+						ED_workspace_delete(workspace, CTX_data_main(C), C, wm);   // XXX hrms, think this over!
+						if (G.debug & G_DEBUG_EVENTS)
+							printf("%s: Workspace delete %p\n", __func__, workspace);
+					}
 					else if (note->data == ND_LAYOUTBROWSE) {
 						bScreen *ref_screen = BKE_workspace_layout_screen_get(note->reference);
 
@@ -455,7 +462,6 @@ void wm_event_do_notifiers(bContext *C)
 				/* pass */
 			}
 			else {
-				ScrArea *sa;
 				ARegion *ar;
 
 				/* XXX context in notifiers? */
@@ -467,8 +473,8 @@ void wm_event_do_notifiers(bContext *C)
 				for (ar = screen->regionbase.first; ar; ar = ar->next) {
 					ED_region_do_listen(screen, NULL, ar, note, scene);
 				}
-				
-				for (sa = screen->areabase.first; sa; sa = sa->next) {
+
+				ED_screen_areas_iter(win, screen, sa) {
 					ED_area_do_listen(screen, sa, note, scene, workspace);
 					for (ar = sa->regionbase.first; ar; ar = ar->next) {
 						ED_region_do_listen(screen, sa, ar, note, scene);
@@ -938,7 +944,18 @@ int WM_operator_call_notest(bContext *C, wmOperator *op)
  */
 int WM_operator_repeat(bContext *C, wmOperator *op)
 {
+#ifdef WITH_REDO_REGION_REMOVAL
+	const OperatorRepeatContextHandle *context_info;
+	int retval;
+
+	context_info = ED_operator_repeat_prepare_context(C, op);
+	retval = wm_operator_exec(C, op, true, true);
+	ED_operator_repeat_reset_context(C, context_info);
+
+	return retval;
+#else
 	return wm_operator_exec(C, op, true, true);
+#endif
 }
 /**
  * \return true if #WM_operator_repeat can run
@@ -1528,17 +1545,22 @@ void wm_event_free_handler(wmEventHandler *handler)
 /* only set context when area/region is part of screen */
 static void wm_handler_op_context(bContext *C, wmEventHandler *handler, const wmEvent *event)
 {
+	wmWindow *win = CTX_wm_window(C);
 	bScreen *screen = CTX_wm_screen(C);
 	
 	if (screen && handler->op) {
 		if (handler->op_area == NULL)
 			CTX_wm_area_set(C, NULL);
 		else {
-			ScrArea *sa;
-			
-			for (sa = screen->areabase.first; sa; sa = sa->next)
-				if (sa == handler->op_area)
+			ScrArea *sa = NULL;
+
+			ED_screen_areas_iter(win, screen, sa_iter) {
+				if (sa_iter == handler->op_area) {
+					sa = sa_iter;
 					break;
+				}
+			}
+
 			if (sa == NULL) {
 				/* when changing screen layouts with running modal handlers (like render display), this
 				 * is not an error to print */
@@ -2493,13 +2515,15 @@ static int wm_event_inside_i(wmEvent *event, rcti *rect)
 
 static ScrArea *area_event_inside(bContext *C, const int xy[2])
 {
+	wmWindow *win = CTX_wm_window(C);
 	bScreen *screen = CTX_wm_screen(C);
-	ScrArea *sa;
 	
-	if (screen)
-		for (sa = screen->areabase.first; sa; sa = sa->next)
+	if (screen) {
+		ED_screen_areas_iter(win, screen, sa) {
 			if (BLI_rcti_isect_pt_v(&sa->totrct, xy))
 				return sa;
+		}
+	}
 	return NULL;
 }
 
@@ -2739,7 +2763,6 @@ void wm_event_do_handlers(bContext *C)
 			wm_tweakevent_test(C, event, action);
 
 			if ((action & WM_HANDLER_BREAK) == 0) {
-				ScrArea *sa;
 				ARegion *ar;
 	
 				/* Note: setting subwin active should be done here, after modal handlers have been done */
@@ -2755,7 +2778,7 @@ void wm_event_do_handlers(bContext *C)
 				}
 #endif
 
-				for (sa = screen->areabase.first; sa; sa = sa->next) {
+				ED_screen_areas_iter(win, screen, sa) {
 					/* after restoring a screen from SCREENMAXIMIZED we have to wait
 					 * with the screen handling till the region coordinates are updated */
 					if (screen->skip_handling == true) {
@@ -2935,24 +2958,26 @@ void WM_event_add_fileselect(bContext *C, wmOperator *op)
 		
 		if (handler->type == WM_HANDLER_FILESELECT) {
 			bScreen *screen = CTX_wm_screen(C);
-			ScrArea *sa;
+			bool cancel_handler = true;
 
 			/* find the area with the file selector for this handler */
-			for (sa = screen->areabase.first; sa; sa = sa->next) {
+			ED_screen_areas_iter(win, screen, sa) {
 				if (sa->spacetype == SPACE_FILE) {
 					SpaceFile *sfile = sa->spacedata.first;
 
 					if (sfile->op == handler->op) {
 						CTX_wm_area_set(C, sa);
 						wm_handler_fileselect_do(C, &win->modalhandlers, handler, EVT_FILESELECT_CANCEL);
+						cancel_handler = false;
 						break;
 					}
 				}
 			}
 
 			/* if not found we stop the handler without changing the screen */
-			if (!sa)
+			if (cancel_handler) {
 				wm_handler_fileselect_do(C, &win->modalhandlers, handler, EVT_FILESELECT_EXTERNAL_CANCEL);
+			}
 		}
 	}
 	
diff --git a/source/blender/windowmanager/intern/wm_operators.c b/source/blender/windowmanager/intern/wm_operators.c
index b6f7603c99f..4c96afff9a1 100644
--- a/source/blender/windowmanager/intern/wm_operators.c
+++ b/source/blender/windowmanager/intern/wm_operators.c
@@ -1498,13 +1498,15 @@ static uiBlock *wm_block_create_redo(bContext *C, ARegion *ar, void *arg_op)
 
 	if (op->type->flag & OPTYPE_MACRO) {
 		for (op = op->macro.first; op; op = op->next) {
-			uiTemplateOperatorPropertyButs(C, layout, op, NULL, 'H', UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
+			uiTemplateOperatorPropertyButs(C, layout, op, NULL, UI_BUT_LABEL_ALIGN_SPLIT_COLUMN,
+			                               UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
 			if (op->next)
 				uiItemS(layout);
 		}
 	}
 	else {
-		uiTemplateOperatorPropertyButs(C, layout, op, NULL, 'H', UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
+		uiTemplateOperatorPropertyButs(C, layout, op, NULL, UI_BUT_LABEL_ALIGN_SPLIT_COLUMN,
+		                               UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
 	}
 	
 	UI_block_bounds_set_popup(block, 4, 0, 0);
@@ -1573,7 +1575,8 @@ static uiBlock *wm_block_dialog_create(bContext *C, ARegion *ar, void *userData)
 
 	layout = UI_block_layout(block, UI_LAYOUT_VERTICAL, UI_LAYOUT_PANEL, 0, 0, data->width, data->height, 0, style);
 	
-	uiTemplateOperatorPropertyButs(C, layout, op, NULL, 'H', UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
+	uiTemplateOperatorPropertyButs(C, layout, op, NULL, UI_BUT_LABEL_ALIGN_SPLIT_COLUMN,
+	                               UI_TEMPLATE_OP_PROPS_SHOW_TITLE);
 	
 	/* clear so the OK button is left alone */
 	UI_block_func_set(block, NULL, NULL, NULL);
@@ -1612,7 +1615,7 @@ static uiBlock *wm_operator_ui_create(bContext *C, ARegion *ar, void *userData)
 	layout = UI_block_layout(block, UI_LAYOUT_VERTICAL, UI_LAYOUT_PANEL, 0, 0, data->width, data->height, 0, style);
 
 	/* since ui is defined the auto-layout args are not used */
-	uiTemplateOperatorPropertyButs(C, layout, op, NULL, 'V', 0);
+	uiTemplateOperatorPropertyButs(C, layout, op, NULL, UI_BUT_LABEL_ALIGN_COLUMN, 0);
 
 	UI_block_func_set(block, NULL, NULL, NULL);
 
diff --git a/source/blender/windowmanager/intern/wm_window.c b/source/blender/windowmanager/intern/wm_window.c
index 9b0d8db68ce..166d97d6b5e 100644
--- a/source/blender/windowmanager/intern/wm_window.c
+++ b/source/blender/windowmanager/intern/wm_window.c
@@ -208,6 +208,8 @@ void wm_window_free(bContext *C, wmWindowManager *wm, wmWindow *win)
 			CTX_wm_window_set(C, NULL);
 	}
 
+	BKE_screen_area_map_free(&win->global_areas);
+
 	/* end running jobs, a job end also removes its timer */
 	for (wt = wm->timers.first; wt; wt = wtnext) {
 		wtnext = wt->next;
@@ -302,6 +304,7 @@ wmWindow *wm_window_copy(bContext *C, wmWindow *win_src, const bool duplicate_la
 	WM_window_set_active_workspace(win_dst, workspace);
 	layout_new = duplicate_layout ? ED_workspace_layout_duplicate(workspace, layout_old, win_dst) : layout_old;
 	WM_window_set_active_layout(win_dst, workspace, layout_new);
+	ED_screen_global_areas_create(win_dst);
 
 	win_dst->drawmethod = U.wmdrawmethod;
 
@@ -782,6 +785,11 @@ void wm_window_ghostwindows_ensure(wmWindowManager *wm)
 			WM_event_add_dropbox_handler(&win->handlers, lb);
 		}
 		wm_window_title(wm, win);
+
+		/* add topbar */
+		if (BLI_listbase_is_empty(&win->global_areas.areabase)) {
+			ED_screen_global_areas_create(win);
+		}
 	}
 }
 
@@ -1008,6 +1016,8 @@ int wm_window_new_exec(bContext *C, wmOperator *op)
 		win_dst->scene = win_src->scene;
 		screen_new->winid = win_dst->winid;
 		CTX_wm_window_set(C, win_dst);
+
+		ED_screen_global_areas_create(win_dst);
 		ED_screen_refresh(CTX_wm_manager(C), win_dst);
 	}
 
@@ -2074,19 +2084,35 @@ float WM_cursor_pressure(const struct wmWindow *win)
 
 /* support for native pixel size */
 /* mac retina opens window in size X, but it has up to 2 x more pixels */
-int WM_window_pixels_x(wmWindow *win)
+int WM_window_pixels_x(const wmWindow *win)
 {
 	float f = GHOST_GetNativePixelSize(win->ghostwin);
 	
 	return (int)(f * (float)win->sizex);
 }
-
-int WM_window_pixels_y(wmWindow *win)
+int WM_window_pixels_y(const wmWindow *win)
 {
 	float f = GHOST_GetNativePixelSize(win->ghostwin);
 	
 	return (int)(f * (float)win->sizey);
-	
+}
+
+/**
+ * Get the total pixels that are usable by the screen-layouts, excluding global areas.
+ */
+int WM_window_screen_pixels_x(const wmWindow *win)
+{
+	return WM_window_pixels_x(win);
+}
+int WM_window_screen_pixels_y(const wmWindow *win)
+{
+	short screen_size_y = WM_window_pixels_y(win);
+
+	for (ScrArea *sa = win->global_areas.areabase.first; sa; sa = sa->next) {
+		screen_size_y -= ED_area_global_size_y(sa);
+	}
+
+	return screen_size_y;
 }
 
 bool WM_window_is_fullscreen(wmWindow *win)