UI: Initial User-Preferences redesign

Implements the first changes for T54115:

* Rename "User Preferences" window to "Settings" in the UI.
  We'll likely put workspace settings in there, separate from the global
  user settings. System settings should become separate from user
  settings in future to allow settings for specific hardware.
* Add sidebar region for navigation (scrolls independently).
  Addresses space problems, so we can add more categories as needed now.
* Increase size of Settings window to compensate new navigation bar.
* Group sections into User Preferences and System.
  Icons for section groups by Andrzej Ambroz. Thanks!
* Bumps subversion for file compatibility.

Screenshot: https://developer.blender.org/F5715337

I also added categories for future work, but commented them out.
We may also want to redesign contents of each section now.

Reviewers: brecht, campbellbarton
Differential Revision: https://developer.blender.org/D3088
Design Task: https://developer.blender.org/T54115

12 files changed, 163 insertions, 29 deletions

diff --git a/source/blender/blenkernel/BKE_blender_version.h b/source/blender/blenkernel/BKE_blender_version.h
index 32b9508a679..b34dc55ba44 100644
--- a/source/blender/blenkernel/BKE_blender_version.h
+++ b/source/blender/blenkernel/BKE_blender_version.h
@@ -28,7 +28,7 @@
  * and keep comment above the defines.
  * Use STRINGIFY() rather than defining with quotes */
 #define BLENDER_VERSION         280
-#define BLENDER_SUBVERSION      33
+#define BLENDER_SUBVERSION      34
 /* Several breakages with 280, e.g. collections vs layers */
 #define BLENDER_MINVERSION      280
 #define BLENDER_MINSUBVERSION   0
diff --git a/source/blender/blenkernel/BKE_screen.h b/source/blender/blenkernel/BKE_screen.h
index 0d766e83299..75d2ed0d0bc 100644
--- a/source/blender/blenkernel/BKE_screen.h
+++ b/source/blender/blenkernel/BKE_screen.h
@@ -319,6 +319,10 @@ void BKE_spacedata_freelist(ListBase *lb);
 void BKE_spacedata_copylist(ListBase *lb1, ListBase *lb2);
 void BKE_spacedata_draw_locks(int set);
 
+struct ARegion *BKE_spacedata_find_region_type(
+        const struct SpaceLink *slink, const struct ScrArea *sa,
+        int region_type) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
+
 void BKE_spacedata_callback_id_remap_set(
         void (*func)(struct ScrArea *sa, struct SpaceLink *sl, struct ID *old_id, struct ID *new_id));
 void BKE_spacedata_id_unref(struct ScrArea *sa, struct SpaceLink *sl, struct ID *id);
@@ -332,7 +336,7 @@ void            BKE_screen_area_free(struct ScrArea *sa);
 void BKE_region_callback_free_gizmomap_set(void (*callback)(struct wmGizmoMap *));
 void BKE_region_callback_refresh_tag_gizmomap_set(void (*callback)(struct wmGizmoMap *));
 
-struct ARegion *BKE_area_find_region_type(struct ScrArea *sa, int type);
+struct ARegion *BKE_area_find_region_type(const struct ScrArea *sa, int type);
 struct ARegion *BKE_area_find_region_active_win(struct ScrArea *sa);
 struct ARegion *BKE_area_find_region_xy(struct ScrArea *sa, const int regiontype, int x, int y);
 struct ScrArea *BKE_screen_find_area_from_space(struct bScreen *sc, struct SpaceLink *sl) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(1, 2);
diff --git a/source/blender/blenkernel/intern/screen.c b/source/blender/blenkernel/intern/screen.c
index 0c93281bf84..e23291d42d4 100644
--- a/source/blender/blenkernel/intern/screen.c
+++ b/source/blender/blenkernel/intern/screen.c
@@ -309,6 +309,30 @@ void BKE_spacedata_draw_locks(int set)
 	}
 }
 
+/**
+ * Version of #BKE_area_find_region_type that also works if \a slink is not the active space of \a sa.
+ */
+ARegion *BKE_spacedata_find_region_type(const SpaceLink *slink, const ScrArea *sa, int region_type)
+{
+	const bool is_slink_active = slink == sa->spacedata.first;
+	const ListBase *regionbase = (is_slink_active) ?
+	                           &sa->regionbase : &slink->regionbase;
+	ARegion *ar = NULL;
+
+	BLI_assert(BLI_findindex(&sa->spacedata, slink) != -1);
+	for (ar = regionbase->first; ar; ar = ar->next) {
+		if (ar->regiontype == region_type) {
+			break;
+		}
+	}
+
+	/* Should really unit test this instead. */
+	BLI_assert(!is_slink_active || ar == BKE_area_find_region_type(sa, region_type));
+
+	return ar;
+}
+
+
 static void (*spacedata_id_remap_cb)(struct ScrArea *sa, struct SpaceLink *sl, ID *old_id, ID *new_id) = NULL;
 
 void BKE_spacedata_callback_id_remap_set(void (*func)(ScrArea *sa, SpaceLink *sl, ID *, ID *))
@@ -644,17 +668,21 @@ void BKE_screen_remove_unused_scrverts(bScreen *sc)
 
 /* ***************** Utilities ********************** */
 
-/* Find a region of the specified type from the given area */
-ARegion *BKE_area_find_region_type(ScrArea *sa, int type)
+/**
+ * Find a region of type \a region_type in the currently active space of \a sa.
+ *
+ * \note This does _not_ work if the region to look up is not in the active
+ *       space. Use #BKE_spacedata_find_region_type if that may be the case.
+ */
+ARegion *BKE_area_find_region_type(const ScrArea *sa, int region_type)
 {
 	if (sa) {
-		ARegion *ar;
-
-		for (ar = sa->regionbase.first; ar; ar = ar->next) {
-			if (ar->regiontype == type)
+		for (ARegion *ar = sa->regionbase.first; ar; ar = ar->next) {
+			if (ar->regiontype == region_type)
 				return ar;
 		}
 	}
+
 	return NULL;
 }
 
diff --git a/source/blender/blenloader/intern/versioning_280.c b/source/blender/blenloader/intern/versioning_280.c
index 2cf00bfe2c1..a844a2dc91b 100644
--- a/source/blender/blenloader/intern/versioning_280.c
+++ b/source/blender/blenloader/intern/versioning_280.c
@@ -2428,6 +2428,29 @@ void blo_do_versions_280(FileData *fd, Library *UNUSED(lib), Main *bmain)
 		}
 	}
 
+	if (!MAIN_VERSION_ATLEAST(bmain, 280, 34)) {
+		for (bScreen *screen = bmain->screen.first; screen; screen = screen->id.next) {
+			for (ScrArea *area = screen->areabase.first; area; area = area->next) {
+				for (SpaceLink *slink = area->spacedata.first; slink; slink = slink->next) {
+					if (slink->spacetype == SPACE_USERPREF) {
+						ARegion *navigation_region = BKE_spacedata_find_region_type(slink, area, RGN_TYPE_NAV_BAR);
+
+						if (!navigation_region) {
+							ListBase *regionbase = (slink == area->spacedata.first) ?
+							                           &area->regionbase : &slink->regionbase;
+
+							navigation_region = MEM_callocN(sizeof(ARegion), "userpref navigation-region do_versions");
+
+							BLI_addhead(regionbase, navigation_region); /* order matters, addhead not addtail! */
+							navigation_region->regiontype = RGN_TYPE_NAV_BAR;
+							navigation_region->alignment = RGN_ALIGN_LEFT;
+						}
+					}
+				}
+			}
+		}
+	}
+
 	{
 		/* Versioning code until next subversion bump goes here. */
 	}
diff --git a/source/blender/editors/include/UI_interface.h b/source/blender/editors/include/UI_interface.h
index dd0070b3b37..dac1ca95eff 100644
--- a/source/blender/editors/include/UI_interface.h
+++ b/source/blender/editors/include/UI_interface.h
@@ -200,6 +200,7 @@ enum {
 
 #define UI_PANEL_WIDTH          340
 #define UI_COMPACT_PANEL_WIDTH  160
+#define UI_NAVIGATION_REGION_WIDTH UI_COMPACT_PANEL_WIDTH
 
 #define UI_PANEL_CATEGORY_MARGIN_WIDTH (U.widget_unit * 1.0f)
 
diff --git a/source/blender/editors/interface/interface_layout.c b/source/blender/editors/interface/interface_layout.c
index 306fa89a062..8a27fd55d37 100644
--- a/source/blender/editors/interface/interface_layout.c
+++ b/source/blender/editors/interface/interface_layout.c
@@ -655,6 +655,7 @@ static void ui_item_enum_expand_exec(
 	uiLayout *layout_radial = NULL;
 	const EnumPropertyItem *item, *item_array;
 	const char *name;
+	char group_name[UI_MAX_NAME_STR];
 	int itemw, icon, value;
 	bool free;
 	bool radial = (layout->root->type == UI_LAYOUT_PIEMENU);
@@ -687,10 +688,22 @@ static void ui_item_enum_expand_exec(
 	}
 
 	for (item = item_array; item->identifier; item++) {
+		const bool is_first = item == item_array;
+
 		if (!item->identifier[0]) {
 			const EnumPropertyItem *next_item = item + 1;
+
+			/* Separate items, potentially with a label. */
 			if (next_item->identifier) {
-				if (radial && layout_radial) {
+				/* Item without identifier but with name: Add group label for the following items. */
+				if (item->name) {
+					if (!is_first) {
+						uiItemS(block->curlayout);
+					}
+					BLI_snprintf(group_name, sizeof(group_name), "%s:", item->name);
+					uiItemL(block->curlayout, group_name, item->icon);
+				}
+				else if (radial && layout_radial) {
 					uiItemS(layout_radial);
 				}
 				else {
diff --git a/source/blender/editors/screen/screen_ops.c b/source/blender/editors/screen/screen_ops.c
index 6a9f1e13aea..2305ce8f5fe 100644
--- a/source/blender/editors/screen/screen_ops.c
+++ b/source/blender/editors/screen/screen_ops.c
@@ -4332,9 +4332,9 @@ static void SCREEN_OT_back_to_previous(struct wmOperatorType *ot)
 /** \name Show User Preferences Operator
  * \{ */
 
-static int userpref_show_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+static int settings_show_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 {
-	int sizex = 800 * UI_DPI_FAC;
+	int sizex = (800 + UI_NAVIGATION_REGION_WIDTH) * UI_DPI_FAC;
 	int sizey = 500 * UI_DPI_FAC;
 
 	/* changes context! */
@@ -4348,15 +4348,15 @@ static int userpref_show_invoke(bContext *C, wmOperator *op, const wmEvent *even
 }
 
 
-static void SCREEN_OT_userpref_show(struct wmOperatorType *ot)
+static void SCREEN_OT_settings_show(struct wmOperatorType *ot)
 {
 	/* identifiers */
-	ot->name = "Show User Preferences";
-	ot->description = "Show user preferences";
-	ot->idname = "SCREEN_OT_userpref_show";
+	ot->name = "Show Blender Settings";
+	ot->description = "Edit user preferences, workspaces and system settings";
+	ot->idname = "SCREEN_OT_settings_show";
 
 	/* api callbacks */
-	ot->invoke = userpref_show_invoke;
+	ot->invoke = settings_show_invoke;
 	ot->poll = ED_operator_screenactive;
 }
 
@@ -4814,7 +4814,7 @@ void ED_operatortypes_screen(void)
 	WM_operatortype_append(SCREEN_OT_back_to_previous);
 	WM_operatortype_append(SCREEN_OT_spacedata_cleanup);
 	WM_operatortype_append(SCREEN_OT_screenshot);
-	WM_operatortype_append(SCREEN_OT_userpref_show);
+	WM_operatortype_append(SCREEN_OT_settings_show);
 	WM_operatortype_append(SCREEN_OT_drivers_editor_show);
 	WM_operatortype_append(SCREEN_OT_region_blend);
 	WM_operatortype_append(SCREEN_OT_space_context_cycle);
diff --git a/source/blender/editors/space_userpref/space_userpref.c b/source/blender/editors/space_userpref/space_userpref.c
index 06c6e612f13..87da461f269 100644
--- a/source/blender/editors/space_userpref/space_userpref.c
+++ b/source/blender/editors/space_userpref/space_userpref.c
@@ -47,6 +47,8 @@
 #include "WM_api.h"
 #include "WM_types.h"
 
+#include "UI_interface.h"
+
 
 
 /* ******************** default callbacks for userpref space ***************** */
@@ -59,6 +61,13 @@ static SpaceLink *userpref_new(const ScrArea *UNUSED(area), const Scene *UNUSED(
 	spref = MEM_callocN(sizeof(SpaceUserPref), "inituserpref");
 	spref->spacetype = SPACE_USERPREF;
 
+	/* navigation region */
+	ar = MEM_callocN(sizeof(ARegion), "navigation region for userpref");
+
+	BLI_addtail(&spref->regionbase, ar);
+	ar->regiontype = RGN_TYPE_NAV_BAR;
+	ar->alignment = RGN_ALIGN_LEFT;
+
 	/* header */
 	ar = MEM_callocN(sizeof(ARegion), "header for userpref");
 
@@ -136,6 +145,19 @@ static void userpref_header_region_draw(const bContext *C, ARegion *ar)
 	ED_region_header(C, ar);
 }
 
+/* add handlers, stuff you only do once or on area/region changes */
+static void userpref_navigation_region_init(wmWindowManager *wm, ARegion *ar)
+{
+	ar->v2d.scroll = V2D_SCROLL_RIGHT | V2D_SCROLL_VERTICAL_HIDE;
+
+	ED_region_panels_init(wm, ar);
+}
+
+static void userpref_navigation_region_draw(const bContext *C, ARegion *ar)
+{
+	ED_region_panels(C, ar);
+}
+
 static void userpref_main_region_listener(
         wmWindow *UNUSED(win), ScrArea *UNUSED(sa), ARegion *UNUSED(ar),
         wmNotifier *UNUSED(wmn), const Scene *UNUSED(scene))
@@ -156,6 +178,13 @@ static void userpref_header_listener(
 #endif
 }
 
+static void userpref_navigation_region_listener(
+        wmWindow *UNUSED(win), ScrArea *UNUSED(sa), ARegion *UNUSED(ar),
+        wmNotifier *UNUSED(wmn), const Scene *UNUSED(scene))
+{
+	/* context changes */
+}
+
 /* only called once, from space/spacetypes.c */
 void ED_spacetype_userpref(void)
 {
@@ -193,6 +222,17 @@ void ED_spacetype_userpref(void)
 
 	BLI_addhead(&st->regiontypes, art);
 
+	/* regions: navigation window */
+	art = MEM_callocN(sizeof(ARegionType), "spacetype userpref region");
+	art->regionid = RGN_TYPE_NAV_BAR;
+	art->prefsizex = UI_NAVIGATION_REGION_WIDTH;
+	art->init = userpref_navigation_region_init;
+	art->draw = userpref_navigation_region_draw;
+	art->listener = userpref_navigation_region_listener;
+	art->keymapflag = ED_KEYMAP_UI;
+
+	BLI_addhead(&st->regiontypes, art);
+
 
 	BKE_spacetype_register(st);
 }
diff --git a/source/blender/makesdna/DNA_userdef_types.h b/source/blender/makesdna/DNA_userdef_types.h
index c9d16351635..0eed17cf1ff 100644
--- a/source/blender/makesdna/DNA_userdef_types.h
+++ b/source/blender/makesdna/DNA_userdef_types.h
@@ -677,16 +677,29 @@ extern UserDef U; /* from blenkernel blender.c */
 
 /* ***************** USERDEF ****************** */
 
+/* Toggles for unfinished 2.8 UserPref design. */
+//#define WITH_USERDEF_WORKSPACES
+//#define WITH_USERDEF_SYSTEM_SPLIT
+
 /* UserDef.userpref (UI active_section) */
 typedef enum eUserPref_Section {
-	USER_SECTION_INTERFACE	= 0,
-	USER_SECTION_EDIT		= 1,
-	USER_SECTION_FILE		= 2,
-	USER_SECTION_SYSTEM		= 3,
-	USER_SECTION_THEME		= 4,
-	USER_SECTION_INPUT		= 5,
-	USER_SECTION_ADDONS 	= 6,
-	USER_SECTION_LIGHT 	= 7,
+	USER_SECTION_INTERFACE         = 0,
+	USER_SECTION_EDIT              = 1,
+	USER_SECTION_SYSTEM_FILES      = 2,
+	USER_SECTION_SYSTEM_GENERAL    = 3,
+	USER_SECTION_THEME             = 4,
+	USER_SECTION_INPUT             = 5,
+	USER_SECTION_ADDONS            = 6,
+	USER_SECTION_LIGHT             = 7,
+#ifdef WITH_USERDEF_WORKSPACES
+	USER_SECTION_WORKSPACE_CONFIG  = 8,
+	USER_SECTION_WORKSPACE_ADDONS  = 9,
+	USER_SECTION_WORKSPACE_KEYMAPS = 10,
+#endif
+#ifdef WITH_USERDEF_SYSTEM_SPLIT
+	USER_SECTION_SYSTEM_DISPLAY    = 11,
+	USER_SECTION_SYSTEM_DEVICES    = 12,
+#endif
 } eUserPref_Section;
 
 /* UserDef.userpref_flag (State of the user preferences UI). */
diff --git a/source/blender/makesrna/intern/rna_userdef.c b/source/blender/makesrna/intern/rna_userdef.c
index 03f86eba601..6ba0d4d3a7c 100644
--- a/source/blender/makesrna/intern/rna_userdef.c
+++ b/source/blender/makesrna/intern/rna_userdef.c
@@ -4925,14 +4925,26 @@ void RNA_def_userdef(BlenderRNA *brna)
 	PropertyRNA *prop;
 
 	static const EnumPropertyItem user_pref_sections[] = {
+		{0, "", ICON_USER, "User Preferences", ""},
 		{USER_SECTION_INTERFACE, "INTERFACE", 0, "Interface", ""},
 		{USER_SECTION_EDIT, "EDITING", 0, "Editing", ""},
 		{USER_SECTION_INPUT, "INPUT", 0, "Input", ""},
 		{USER_SECTION_ADDONS, "ADDONS", 0, "Add-ons", ""},
 		{USER_SECTION_THEME, "THEMES", 0, "Themes", ""},
 		{USER_SECTION_LIGHT, "LIGHTS", 0, "Lights", ""},
-		{USER_SECTION_FILE, "FILES", 0, "File", ""},
-		{USER_SECTION_SYSTEM, "SYSTEM", 0, "System", ""},
+#ifdef WITH_USERDEF_WORKSPACES
+		{0, "", ICON_WORKSPACE, "Workspaces", ""},
+		{USER_SECTION_WORKSPACE_CONFIG, "WORKSPACE_CONFIG", 0, "Configuration File", ""},
+		{USER_SECTION_WORKSPACE_ADDONS, "WORKSPACE_ADDONS", 0, "Add-on Overrides", ""},
+		{USER_SECTION_WORKSPACE_KEYMAPS, "WORKSPACE_KEYMAPS", 0, "Keymap Overrides", ""},
+#endif
+		{0, "", ICON_SYSTEM, "System", ""},
+		{USER_SECTION_SYSTEM_GENERAL, "SYSTEM_GENERAL", 0, "General", ""},
+		{USER_SECTION_SYSTEM_FILES,   "SYSTEM_FILES",   0, "Files",   ""},
+#ifdef WITH_USERDEF_SYSTEM_SPLIT
+		{USER_SECTION_SYSTEM_DISPLAY, "SYSTEM_DISPLAY", 0, "Display", ""},
+		{USER_SECTION_SYSTEM_DEVICES, "SYSTEM_DEVICES", 0, "Devices", ""},
+#endif
 		{0, NULL, 0, NULL, NULL}
 	};
 
diff --git a/source/blender/windowmanager/intern/wm_files.c b/source/blender/windowmanager/intern/wm_files.c
index d90ad24dc16..96a6538a043 100644
--- a/source/blender/windowmanager/intern/wm_files.c
+++ b/source/blender/windowmanager/intern/wm_files.c
@@ -1659,7 +1659,7 @@ static int wm_userpref_write_exec(bContext *C, wmOperator *op)
 
 void WM_OT_save_userpref(wmOperatorType *ot)
 {
-	ot->name = "Save User Preferences";
+	ot->name = "Save Settings";
 	ot->idname = "WM_OT_save_userpref";
 	ot->description = "Save user preferences separately, overrides startup file preferences";
 
diff --git a/source/blender/windowmanager/intern/wm_window.c b/source/blender/windowmanager/intern/wm_window.c
index b644457e593..14b13fce652 100644
--- a/source/blender/windowmanager/intern/wm_window.c
+++ b/source/blender/windowmanager/intern/wm_window.c
@@ -954,7 +954,7 @@ wmWindow *WM_window_open_temp(bContext *C, int x, int y, int sizex, int sizey, i
 	if (sa->spacetype == SPACE_IMAGE)
 		title = IFACE_("Blender Render");
 	else if (ELEM(sa->spacetype, SPACE_OUTLINER, SPACE_USERPREF))
-		title = IFACE_("Blender User Preferences");
+		title = IFACE_("Blender Settings");
 	else if (sa->spacetype == SPACE_FILE)
 		title = IFACE_("Blender File View");
 	else if (sa->spacetype == SPACE_IPO)