UI: Global "Status-bar" Area (WIP)

* Add horizontal bar at bottom of all non-temp windows, similar to the Top-bar.
* Status-bar is hidden in UI-less fullscreen mode
* Current contents are preliminary and based on T54861:
** Left: Current file-path if needed. "(Modified)" note if file was changed.
** Center: Scene statistics (like in 2.7 Info Editor).
** Right: Progress-bars and reports
* Internally managed as own "STATUSBAR" editor-type (hidden in UI).
* Like with the Top-bar, Status-bar data and SDNA writing is disabled.
* Most changes in low-level screen/area code are to support layout bounds that differ from window bounds.

Design task: T54861
Main changes approved by @brecht.

1 files changed, 8 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_screen_types.h b/source/blender/makesdna/DNA_screen_types.h
index 1f14bb58e78..ef0dbceef38 100644
--- a/source/blender/makesdna/DNA_screen_types.h
+++ b/source/blender/makesdna/DNA_screen_types.h
@@ -227,7 +227,7 @@ typedef struct uiPreview {           /* some preview UI data need to be saved in
 } uiPreview;
 
 /* These two lines with # tell makesdna this struct can be excluded.
- * Should be: #ifndef WITH_TOPBAR_WRITING */
+ * Should be: #ifndef WITH_GLOBAL_AREA_WRITING */
 #
 #
 typedef struct ScrGlobalAreaData {
@@ -240,14 +240,21 @@ typedef struct ScrGlobalAreaData {
 	 * if they are 'collapsed' or not. Value is set on area creation and not
 	 * touched afterwards. */
 	short size_min, size_max;
+	short align; /* GlobalAreaAlign */
 
 	short flag; /* GlobalAreaFlag */
+	short pad;
 } ScrGlobalAreaData;
 
 enum GlobalAreaFlag {
 	GLOBAL_AREA_IS_HIDDEN = (1 << 0),
 };
 
+typedef enum GlobalAreaAlign {
+	GLOBAL_AREA_ALIGN_TOP,
+	GLOBAL_AREA_ALIGN_BOTTOM,
+} GlobalAreaAlign;
+
 typedef struct ScrArea_Runtime {
 	struct bToolRef *tool;
 	char          is_tool_set;