UI: Preferences Redesign Part 2

(Part 1 was 00963afc14978b)

Does the following changes visible to users:
* Use panels and sub-panels for more structured & logical grouping
* Re-organized options more logically than before (see images in D4148)
* Use flow layout (single column by default).
* New layout uses horizontal margin if there's enough space.
* Change size of Preferences window to suit new layout.
* Move keymap related options from "Input" into own section.
* Own, left-bottom aligned region for Save Preferences button.
* Adjustments of names, tooltips & icons.
* Move buttons from header into the main region (except editor switch).
* Hide Preferences header when opened in temporary window.
* Use full area width for header.
* Don't use slider but regular number widget for UI scale.
* Gray out animation player path option if player isn't "Custom"

Internal changes:
* Rearrange RNA properties to match changed UI structure.
* Introduces new "EXECUTE" region type, see reasoning in D3982.
* Changes to panel layout and AZone code for dynamic panel region.
* Bumps subversion and does versioning for new regions.

RNA changes are documented in the release notes:
https://wiki.blender.org/wiki/Reference/Release_Notes/2.80/Python_API/Preferences_API

Design & implementation mostly done by @billreynish and myself.
I recommend checking out the screenshots posted by William:
https://developer.blender.org/D4148#93787

Reviewed By: brecht

Maniphest Tasks: T54115

Differential Revision: https://developer.blender.org/D4148

4 files changed, 61 insertions, 65 deletions

diff --git a/source/blender/editors/screen/area.c b/source/blender/editors/screen/area.c
index 47c44468bc7..34a20c8ccf7 100644
--- a/source/blender/editors/screen/area.c
+++ b/source/blender/editors/screen/area.c
@@ -187,52 +187,6 @@ void ED_area_do_refresh(bContext *C, ScrArea *sa)
 }
 
 /**
- * Action zones are only updated if the mouse is inside of them, but in some cases (currently only fullscreen icon)
- * it might be needed to update their properties and redraw if the mouse isn't inside.
- */
-void ED_area_azones_update(ScrArea *sa, const int mouse_xy[2])
-{
-	AZone *az;
-	bool changed = false;
-
-	for (az = sa->actionzones.first; az; az = az->next) {
-		if (az->type == AZONE_FULLSCREEN) {
-			/* only if mouse is not hovering the azone */
-			if (BLI_rcti_isect_pt_v(&az->rect, mouse_xy) == false) {
-				az->alpha = 0.0f;
-				changed = true;
-
-				/* can break since currently only this is handled here */
-				break;
-			}
-		}
-		else if (az->type == AZONE_REGION_SCROLL) {
-			/* only if mouse is not hovering the azone */
-			if (BLI_rcti_isect_pt_v(&az->rect, mouse_xy) == false) {
-				View2D *v2d = &az->ar->v2d;
-
-				if (az->direction == AZ_SCROLL_VERT) {
-					az->alpha = v2d->alpha_vert = 0;
-					changed = true;
-				}
-				else if (az->direction == AZ_SCROLL_HOR) {
-					az->alpha = v2d->alpha_hor = 0;
-					changed = true;
-				}
-				else {
-					BLI_assert(0);
-				}
-			}
-		}
-	}
-
-	if (changed) {
-		sa->flag &= ~AREA_FLAG_ACTIONZONES_UPDATE;
-		ED_area_tag_redraw_no_rebuild(sa);
-	}
-}
-
-/**
  * \brief Corner widget use for quitting fullscreen.
  */
 static void area_draw_azone_fullscreen(short x1, short y1, short x2, short y2, float alpha)
@@ -412,18 +366,11 @@ static void region_draw_azones(ScrArea *sa, ARegion *ar)
 			}
 			else if (az->type == AZONE_FULLSCREEN) {
 				area_draw_azone_fullscreen(az->x1, az->y1, az->x2, az->y2, az->alpha);
-
-				if (az->alpha != 0.0f) {
-					area_azone_tag_update(sa);
-				}
-			}
-			else if (az->type == AZONE_REGION_SCROLL) {
-				if (az->alpha != 0.0f) {
-					area_azone_tag_update(sa);
-				}
-				/* Don't draw this azone. */
 			}
 		}
+		if (!IS_EQF(az->alpha, 0.0f) && ELEM(az->type, AZONE_FULLSCREEN, AZONE_REGION_SCROLL)) {
+			area_azone_tag_update(sa);
+		}
 	}
 
 	GPU_matrix_pop();
@@ -1605,6 +1552,7 @@ void ED_area_update_region_sizes(wmWindowManager *wm, wmWindow *win, ScrArea *ar
 	if (!(area->flag & AREA_FLAG_REGION_SIZE_UPDATE)) {
 		return;
 	}
+	const bScreen *screen = WM_window_get_active_screen(win);
 
 	WM_window_rect_calc(win, &window_rect);
 	area_calc_totrct(area, &window_rect);
@@ -1614,6 +1562,9 @@ void ED_area_update_region_sizes(wmWindowManager *wm, wmWindow *win, ScrArea *ar
 	overlap_rect = rect;
 	region_rect_recursive(area, area->regionbase.first, &rect, &overlap_rect, 0);
 
+	/* Dynamically sized regions may have changed region sizes, so we have to force azone update. */
+	area_azone_initialize(win, screen, area);
+
 	for (ARegion *ar = area->regionbase.first; ar; ar = ar->next) {
 		region_subwindow(ar);
 
@@ -1621,7 +1572,11 @@ void ED_area_update_region_sizes(wmWindowManager *wm, wmWindow *win, ScrArea *ar
 		if (ar->type->init) {
 			ar->type->init(wm, ar);
 		}
+
+		/* Some AZones use View2D data which is only updated in region init, so call that first! */
+		region_azones_add(screen, area, ar, ar->alignment & ~RGN_SPLIT_PREV);
 	}
+	ED_area_azones_update(area, &win->eventstate->x);
 
 	area->flag &= ~AREA_FLAG_REGION_SIZE_UPDATE;
 }
@@ -2386,6 +2341,9 @@ void ED_region_panels_draw(const bContext *C, ARegion *ar)
 	/* set the view */
 	UI_view2d_view_ortho(v2d);
 
+	/* View2D matrix might have changed due to dynamic sized regions. */
+	UI_blocklist_update_window_matrix(C, &ar->uiblocks);
+
 	/* draw panels */
 	UI_panels_draw(C, ar);
 
diff --git a/source/blender/editors/screen/screen_edit.c b/source/blender/editors/screen/screen_edit.c
index 62d60c39c0c..7e6e31d339d 100644
--- a/source/blender/editors/screen/screen_edit.c
+++ b/source/blender/editors/screen/screen_edit.c
@@ -639,7 +639,7 @@ void ED_screen_set_active_region(bContext *C, wmWindow *win, const int xy[2])
 		ED_screen_areas_iter(win, scr, area_iter) {
 			if (xy[0] > area_iter->totrct.xmin && xy[0] < area_iter->totrct.xmax) {
 				if (xy[1] > area_iter->totrct.ymin && xy[1] < area_iter->totrct.ymax) {
-					if (ED_area_actionzone_refresh_xy(area_iter, xy) == NULL) {
+					if (ED_area_azones_update(area_iter, xy) == NULL) {
 						sa = area_iter;
 						break;
 					}
@@ -1251,7 +1251,7 @@ 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)) {
+				if (ELEM(ar->regiontype, RGN_TYPE_UI, RGN_TYPE_HEADER, RGN_TYPE_TOOLS, RGN_TYPE_NAV_BAR, RGN_TYPE_EXECUTE)) {
 					ar->flag |= RGN_FLAG_HIDDEN;
 				}
 			}
diff --git a/source/blender/editors/screen/screen_intern.h b/source/blender/editors/screen/screen_intern.h
index 7722f2c9fcc..5f36f4a06ab 100644
--- a/source/blender/editors/screen/screen_intern.h
+++ b/source/blender/editors/screen/screen_intern.h
@@ -57,7 +57,6 @@ int         screen_area_join(struct bContext *C, bScreen *scr, ScrArea *sa1, Scr
 int         area_getorientation(ScrArea *sa, ScrArea *sb);
 
 struct AZone *ED_area_actionzone_find_xy(ScrArea *sa, const int xy[2]);
-struct AZone *ED_area_actionzone_refresh_xy(ScrArea *sa, const int xy[2]);
 
 /* screen_geometry.c */
 int         screen_geom_area_height(const ScrArea *area);
diff --git a/source/blender/editors/screen/screen_ops.c b/source/blender/editors/screen/screen_ops.c
index d41bf8d937b..62b4db94937 100644
--- a/source/blender/editors/screen/screen_ops.c
+++ b/source/blender/editors/screen/screen_ops.c
@@ -798,6 +798,32 @@ static AZone *area_actionzone_refresh_xy(ScrArea *sa, const int xy[2], const boo
 				}
 			}
 		}
+		else if (!test_only && !IS_EQF(az->alpha, 0.0f)) {
+			bool changed = false;
+
+			if (az->type == AZONE_FULLSCREEN) {
+				az->alpha = 0.0f;
+				changed = true;
+			}
+			else if (az->type == AZONE_REGION_SCROLL) {
+				if (az->direction == AZ_SCROLL_VERT) {
+					az->alpha = az->ar->v2d.alpha_vert = 0;
+					changed = true;
+				}
+				else if (az->direction == AZ_SCROLL_HOR) {
+					az->alpha = az->ar->v2d.alpha_hor = 0;
+					changed = true;
+				}
+				else {
+					BLI_assert(0);
+				}
+			}
+
+			if (changed) {
+				sa->flag &= ~AREA_FLAG_ACTIONZONES_UPDATE;
+				ED_area_tag_redraw_no_rebuild(sa);
+			}
+		}
 	}
 
 	return az;
@@ -808,7 +834,7 @@ AZone *ED_area_actionzone_find_xy(ScrArea *sa, const int xy[2])
 	return area_actionzone_refresh_xy(sa, xy, true);
 }
 
-AZone *ED_area_actionzone_refresh_xy(ScrArea *sa, const int xy[2])
+AZone *ED_area_azones_update(ScrArea *sa, const int xy[2])
 {
 	return area_actionzone_refresh_xy(sa, xy, false);
 }
@@ -2382,8 +2408,12 @@ static int region_scale_modal(bContext *C, wmOperator *op, const wmEvent *event)
 					if (!(rmd->ar->flag & RGN_FLAG_HIDDEN))
 						region_scale_toggle_hidden(C, rmd);
 				}
-				else if (rmd->ar->flag & RGN_FLAG_HIDDEN)
+				else if (rmd->ar->flag & RGN_FLAG_HIDDEN) {
 					region_scale_toggle_hidden(C, rmd);
+				}
+				else if (rmd->ar->flag & RGN_FLAG_DYNAMIC_SIZE) {
+					rmd->ar->sizex = rmd->origval;
+				}
 			}
 			else {
 				int maxsize = region_scale_get_maxsize(rmd);
@@ -2411,10 +2441,15 @@ static int region_scale_modal(bContext *C, wmOperator *op, const wmEvent *event)
 					if (!(rmd->ar->flag & RGN_FLAG_HIDDEN))
 						region_scale_toggle_hidden(C, rmd);
 				}
-				else if (maxsize > 0 && (rmd->ar->sizey > maxsize))
+				else if (maxsize > 0 && (rmd->ar->sizey > maxsize)) {
 					rmd->ar->sizey = maxsize;
-				else if (rmd->ar->flag & RGN_FLAG_HIDDEN)
+				}
+				else if (rmd->ar->flag & RGN_FLAG_HIDDEN) {
 					region_scale_toggle_hidden(C, rmd);
+				}
+				else if (rmd->ar->flag & RGN_FLAG_DYNAMIC_SIZE) {
+					rmd->ar->sizey = rmd->origval;
+				}
 			}
 			ED_area_tag_redraw(rmd->sa);
 			WM_event_add_notifier(C, NC_SCREEN | NA_EDITED, NULL);
@@ -4349,11 +4384,15 @@ static void SCREEN_OT_back_to_previous(struct wmOperatorType *ot)
 
 static int userpref_show_invoke(bContext *C, wmOperator *op, const wmEvent *event)
 {
-	int sizex = (800 + UI_NAVIGATION_REGION_WIDTH) * UI_DPI_FAC;
-	int sizey = 500 * UI_DPI_FAC;
+	int sizex = (500 + UI_NAVIGATION_REGION_WIDTH) * UI_DPI_FAC;
+	int sizey = 520 * UI_DPI_FAC;
 
 	/* changes context! */
 	if (WM_window_open_temp(C, event->x, event->y, sizex, sizey, WM_WINDOW_USERPREFS) != NULL) {
+		/* The header only contains the editor switcher and looks empty. So hiding in the temp window makes sense. */
+		ScrArea *area = CTX_wm_area(C);
+		ARegion *region = BKE_area_find_region_type(area, RGN_TYPE_HEADER);
+		region->flag |= RGN_FLAG_HIDDEN;
 		return OPERATOR_FINISHED;
 	}
 	else {