Interface: New region type 'Footer', used by text editor

* It can be hidden by dragging it up/down.
* It can be at the top or bottom, independent of the header.
* It uses the color theme from the header.
* It does not change its color, when the area becomes active.

Currently, it is used in the text editor to display the file path.

Differential Revision: https://developer.blender.org/D4601

3 files changed, 160 insertions, 17 deletions

diff --git a/source/blender/editors/screen/area.c b/source/blender/editors/screen/area.c
index 886f2781312..0150127d6fb 100644
--- a/source/blender/editors/screen/area.c
+++ b/source/blender/editors/screen/area.c
@@ -1111,15 +1111,9 @@ bool ED_region_is_overlap(int spacetype, int regiontype)
 			}
 		}
 		else if (ELEM(spacetype, SPACE_VIEW3D, SPACE_IMAGE)) {
-			if (ELEM(regiontype, RGN_TYPE_TOOLS, RGN_TYPE_UI, RGN_TYPE_TOOL_PROPS)) {
+			if (ELEM(regiontype, RGN_TYPE_TOOLS, RGN_TYPE_UI, RGN_TYPE_TOOL_PROPS, RGN_TYPE_HEADER, RGN_TYPE_FOOTER)) {
 				return true;
 			}
-
-			if (ELEM(spacetype, SPACE_VIEW3D, SPACE_IMAGE)) {
-				if (regiontype == RGN_TYPE_HEADER) {
-					return true;
-				}
-			}
 		}
 	}
 
@@ -1167,6 +1161,9 @@ static void region_rect_recursive(ScrArea *sa, ARegion *ar, rcti *remainder, rct
 	else if (ar->regiontype == RGN_TYPE_HEADER) {
 		prefsizey = ED_area_headersize();
 	}
+	else if (ar->regiontype == RGN_TYPE_FOOTER) {
+		prefsizey = ED_area_footersize();
+	}
 	else if (ED_area_is_global(sa)) {
 		prefsizey = ED_region_global_size_y();
 	}
@@ -1520,6 +1517,11 @@ static void ed_default_handlers(wmWindowManager *wm, ScrArea *sa, ARegion *ar, L
 		wmKeyMap *keymap = WM_keymap_ensure(wm->defaultconf, "Header", 0, 0);
 		WM_event_add_keymap_handler(handlers, keymap);
 	}
+	if (flag & ED_KEYMAP_FOOTER) {
+		/* standard keymap for footer regions */
+		wmKeyMap *keymap = WM_keymap_ensure(wm->defaultconf, "Footer", 0, 0);
+		WM_event_add_keymap_handler(handlers, keymap);
+	}
 
 	/* Keep last because of LMB/RMB handling, see: T57527. */
 	if (flag & ED_KEYMAP_GPENCIL) {
@@ -1910,10 +1912,25 @@ void ED_area_newspace(bContext *C, ScrArea *sa, int type, const bool skip_ar_exi
 
 		/* Sync header alignment. */
 		if (sync_header_alignment) {
-			for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
-				if (ar->regiontype == RGN_TYPE_HEADER) {
-					ar->alignment = header_alignment;
-					break;
+			/* Spaces with footer. */
+			if (st->spaceid == SPACE_TEXT){
+				for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
+					if (ar->regiontype == RGN_TYPE_HEADER) {
+						ar->alignment = header_alignment;
+					}
+					if (ar->regiontype == RGN_TYPE_FOOTER) {
+						int footer_alignment = (header_alignment == RGN_ALIGN_BOTTOM) ? RGN_ALIGN_TOP : RGN_ALIGN_BOTTOM;
+						ar->alignment = footer_alignment;
+						break;
+					}
+				}
+			}
+			else {
+				for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
+					if (ar->regiontype == RGN_TYPE_HEADER) {
+						ar->alignment = header_alignment;
+						break;
+					}
 				}
 			}
 		}
@@ -2538,6 +2555,27 @@ int ED_area_header_alignment(const ScrArea *area)
 	        area, (U.uiflag & USER_HEADER_BOTTOM) ? RGN_ALIGN_BOTTOM : RGN_ALIGN_TOP);
 }
 
+int ED_area_footersize(void)
+{
+	return ED_area_headersize();
+}
+
+int ED_area_footer_alignment_or_fallback(const ScrArea *area, int fallback)
+{
+	for (ARegion *ar = area->regionbase.first; ar; ar = ar->next) {
+		if (ar->regiontype == RGN_TYPE_FOOTER) {
+			return ar->alignment;
+		}
+	}
+	return fallback;
+}
+
+int ED_area_footer_alignment(const ScrArea *area)
+{
+	return ED_area_footer_alignment_or_fallback(
+			area, (U.uiflag & USER_HEADER_BOTTOM) ? RGN_ALIGN_TOP : RGN_ALIGN_BOTTOM);
+}
+
 /**
  * \return the final height of a global \a area, accounting for DPI.
  */
diff --git a/source/blender/editors/screen/screen_edit.c b/source/blender/editors/screen/screen_edit.c
index cd5b557f986..41ce5455c3b 100644
--- a/source/blender/editors/screen/screen_edit.c
+++ b/source/blender/editors/screen/screen_edit.c
@@ -421,7 +421,11 @@ static void screen_refresh_headersizes(void)
 	SpaceType *st;
 
 	for (st = lb->first; st; st = st->next) {
-		ARegionType *art = BKE_regiontype_from_id(st, RGN_TYPE_HEADER);
+		ARegionType *art;
+		art = BKE_regiontype_from_id(st, RGN_TYPE_HEADER);
+		if (art) art->prefsizey = ED_area_headersize();
+
+		art = BKE_regiontype_from_id(st, RGN_TYPE_FOOTER);
 		if (art) art->prefsizey = ED_area_headersize();
 	}
 }
@@ -1259,7 +1263,8 @@ ScrArea *ED_screen_state_toggle(bContext *C, wmWindow *win, ScrArea *sa, const s
 			for (ar = newa->regionbase.first; ar; ar = ar->next) {
 				ar->flagfullscreen = ar->flag;
 
-				if (ELEM(ar->regiontype, RGN_TYPE_UI, RGN_TYPE_HEADER, RGN_TYPE_TOOLS, RGN_TYPE_NAV_BAR, RGN_TYPE_EXECUTE)) {
+				if (ELEM(ar->regiontype, RGN_TYPE_UI, RGN_TYPE_HEADER, RGN_TYPE_FOOTER,
+				                         RGN_TYPE_TOOLS, RGN_TYPE_NAV_BAR, RGN_TYPE_EXECUTE)) {
 					ar->flag |= RGN_FLAG_HIDDEN;
 				}
 			}
diff --git a/source/blender/editors/screen/screen_ops.c b/source/blender/editors/screen/screen_ops.c
index ed96621a906..09ca0476b10 100644
--- a/source/blender/editors/screen/screen_ops.c
+++ b/source/blender/editors/screen/screen_ops.c
@@ -2317,12 +2317,13 @@ static int area_max_regionsize(ScrArea *sa, ARegion *scalear, AZEdge edge)
 				dist -= ar->winx;
 			}
 			else if (scalear->alignment == RGN_ALIGN_TOP &&
-			         (ar->alignment == RGN_ALIGN_BOTTOM || ar->regiontype == RGN_TYPE_HEADER))
+			         (ar->alignment == RGN_ALIGN_BOTTOM || ELEM(ar->regiontype, RGN_TYPE_HEADER, RGN_TYPE_FOOTER)))
 			{
 				dist -= ar->winy;
 			}
 			else if (scalear->alignment == RGN_ALIGN_BOTTOM &&
-			         (ar->alignment == RGN_ALIGN_TOP || ar->regiontype == RGN_TYPE_HEADER)) {
+			         (ar->alignment == RGN_ALIGN_TOP || ELEM(ar->regiontype, RGN_TYPE_HEADER, RGN_TYPE_FOOTER)))
+			{
 				dist -= ar->winy;
 			}
 		}
@@ -2469,8 +2470,8 @@ static int region_scale_modal(bContext *C, wmOperator *op, const wmEvent *event)
 				}
 				CLAMP(rmd->ar->sizey, 0, rmd->maxsize);
 
-				/* note, 'UI_UNIT_Y/4' means you need to drag the header almost
-				 * all the way down for it to become hidden, this is done
+				/* note, 'UI_UNIT_Y/4' means you need to drag the footer and execute region
+				 * almost all the way down for it to become hidden, this is done
 				 * otherwise its too easy to do this by accident */
 				if (rmd->ar->sizey < UI_UNIT_Y / 4) {
 					rmd->ar->sizey = rmd->origval;
@@ -3850,6 +3851,103 @@ static void SCREEN_OT_header_context_menu(wmOperatorType *ot)
 /** \} */
 
 /* -------------------------------------------------------------------- */
+/** \name Footer Toggle Operator
+ * \{ */
+
+static int footer_exec(bContext *C, wmOperator *UNUSED(op))
+{
+	ARegion *ar = screen_find_region_type(C, RGN_TYPE_FOOTER);
+
+	if (ar == NULL) {
+		return OPERATOR_CANCELLED;
+	}
+
+	ar->flag ^= RGN_FLAG_HIDDEN;
+
+	ED_area_tag_redraw(CTX_wm_area(C));
+
+	WM_event_add_notifier(C, NC_SCREEN | NA_EDITED, NULL);
+
+	return OPERATOR_FINISHED;
+}
+
+static void SCREEN_OT_footer(wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name = "Toggle Footer";
+	ot->description = "Toggle footer display";
+	ot->idname = "SCREEN_OT_footer";
+
+	/* api callbacks */
+	ot->exec = footer_exec;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Footer Tools Operator
+ * \{ */
+
+static bool footer_context_menu_poll(bContext *C)
+{
+	ScrArea *sa = CTX_wm_area(C);
+	return sa;
+}
+
+void ED_screens_footer_tools_menu_create(bContext *C, uiLayout *layout, void *UNUSED(arg))
+{
+	ScrArea *sa = CTX_wm_area(C);
+	ARegion *ar = CTX_wm_region(C);
+	const char *but_flip_str = (ar->alignment == RGN_ALIGN_TOP) ? IFACE_("Flip to Bottom") : IFACE_("Flip to Top");
+
+	uiItemO(layout, IFACE_("Toggle Footer"), ICON_NONE, "SCREEN_OT_footer");
+
+	/* default is WM_OP_INVOKE_REGION_WIN, which we don't want here. */
+	uiLayoutSetOperatorContext(layout, WM_OP_INVOKE_DEFAULT);
+
+	uiItemO(layout, but_flip_str, ICON_NONE, "SCREEN_OT_region_flip");
+
+
+	/* file browser should be fullscreen all the time, topbar should
+	 * never be. But other regions can be maximized/restored... */
+	if (!ELEM(sa->spacetype, SPACE_FILE, SPACE_TOPBAR)) {
+		uiItemS(layout);
+
+		const char *but_str = sa->full ? IFACE_("Tile Area") : IFACE_("Maximize Area");
+		uiItemO(layout, but_str, ICON_NONE, "SCREEN_OT_screen_full_area");
+	}
+}
+
+static int footer_context_menu_invoke(bContext *C, wmOperator *UNUSED(op), const wmEvent *UNUSED(event))
+{
+	uiPopupMenu *pup;
+	uiLayout *layout;
+
+	pup = UI_popup_menu_begin(C, IFACE_("Footer"), ICON_NONE);
+	layout = UI_popup_menu_layout(pup);
+
+	ED_screens_footer_tools_menu_create(C, layout, NULL);
+
+	UI_popup_menu_end(C, pup);
+
+	return OPERATOR_INTERFACE;
+}
+
+static void SCREEN_OT_footer_context_menu(wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name = "Footer Context Menu";
+	ot->description = "Display footer region context menu";
+	ot->idname = "SCREEN_OT_footer_context_menu";
+
+	/* api callbacks */
+	ot->poll = footer_context_menu_poll;
+	ot->invoke = footer_context_menu_invoke;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
 /** \name Navigation Bar Tools Menu
  * \{ */
 
@@ -4968,6 +5066,8 @@ void ED_operatortypes_screen(void)
 	WM_operatortype_append(SCREEN_OT_header);
 	WM_operatortype_append(SCREEN_OT_header_toggle_menus);
 	WM_operatortype_append(SCREEN_OT_header_context_menu);
+	WM_operatortype_append(SCREEN_OT_footer);
+	WM_operatortype_append(SCREEN_OT_footer_context_menu);
 	WM_operatortype_append(SCREEN_OT_screen_set);
 	WM_operatortype_append(SCREEN_OT_screen_full_area);
 	WM_operatortype_append(SCREEN_OT_back_to_previous);