From e8876b26b918672ec1472149b16c51945bdbbe5f Mon Sep 17 00:00:00 2001
From: tokyo4j <hrak1529@gmail.com>
Date: Sat, 5 Jul 2025 16:07:04 +0900
Subject: [PATCH] overlay: take into account <core><gap> for region overlay

---
 include/view.h |  1 +
 src/overlay.c  |  3 +-
 src/view.c     | 90 +++++++++++++++++++++++++++-----------------------
 3 files changed, 52 insertions(+), 42 deletions(-)

diff --git a/include/view.h b/include/view.h
index 04ed7d64..a7aa1af0 100644
--- a/include/view.h
+++ b/include/view.h
@@ -504,6 +504,7 @@ enum view_edge view_edge_invert(enum view_edge edge);
 /* If view is NULL, the size of SSD is not considered */
 struct wlr_box view_get_edge_snap_box(struct view *view, struct output *output,
 	enum view_edge edge);
+struct wlr_box view_get_region_snap_box(struct view *view, struct region *region);
 
 /**
  * view_is_focusable() - Check whether or not a view can be focused
diff --git a/src/overlay.c b/src/overlay.c
index 3424f160..2aecf007 100644
--- a/src/overlay.c
+++ b/src/overlay.c
@@ -111,7 +111,8 @@ show_region_overlay(struct seat *seat, struct region *region)
 	inactivate_overlay(&seat->overlay);
 	seat->overlay.active.region = region;
 
-	show_overlay(seat, &seat->overlay.region_rect, &region->geo);
+	struct wlr_box geo = view_get_region_snap_box(NULL, region);
+	show_overlay(seat, &seat->overlay.region_rect, &geo);
 }
 
 static struct wlr_box get_edge_snap_box(enum view_edge edge, struct output *output)
diff --git a/src/view.c b/src/view.c
index 2f6e6277..99a597cc 100644
--- a/src/view.c
+++ b/src/view.c
@@ -1195,6 +1195,54 @@ view_apply_natural_geometry(struct view *view)
 	view_move_resize(view, geometry);
 }
 
+struct wlr_box
+view_get_region_snap_box(struct view *view, struct region *region)
+{
+	struct wlr_box geo = region->geo;
+
+	/* Adjust for rc.gap */
+	if (rc.gap) {
+		double half_gap = rc.gap / 2.0;
+		struct wlr_fbox offset = {
+			.x = half_gap,
+			.y = half_gap,
+			.width = -rc.gap,
+			.height = -rc.gap
+		};
+		struct wlr_box usable =
+			output_usable_area_in_layout_coords(region->output);
+		if (geo.x == usable.x) {
+			offset.x += half_gap;
+			offset.width -= half_gap;
+		}
+		if (geo.y == usable.y) {
+			offset.y += half_gap;
+			offset.height -= half_gap;
+		}
+		if (geo.x + geo.width == usable.x + usable.width) {
+			offset.width -= half_gap;
+		}
+		if (geo.y + geo.height == usable.y + usable.height) {
+			offset.height -= half_gap;
+		}
+		geo.x += offset.x;
+		geo.y += offset.y;
+		geo.width += offset.width;
+		geo.height += offset.height;
+	}
+
+	/* And adjust for current view */
+	if (view) {
+		struct border margin = ssd_get_margin(view->ssd);
+		geo.x += margin.left;
+		geo.y += margin.top;
+		geo.width -= margin.left + margin.right;
+		geo.height -= margin.top + margin.bottom;
+	}
+
+	return geo;
+}
+
 static void
 view_apply_region_geometry(struct view *view)
 {
@@ -1220,47 +1268,7 @@ view_apply_region_geometry(struct view *view)
 		}
 	}
 
-	/* Create a copy of the original region geometry */
-	struct wlr_box geo = view->tiled_region->geo;
-
-	/* Adjust for rc.gap */
-	if (rc.gap) {
-		double half_gap = rc.gap / 2.0;
-		struct wlr_fbox offset = {
-			.x = half_gap,
-			.y = half_gap,
-			.width = -rc.gap,
-			.height = -rc.gap
-		};
-		struct wlr_box usable =
-			output_usable_area_in_layout_coords(output);
-		if (geo.x == usable.x) {
-			offset.x += half_gap;
-			offset.width -= half_gap;
-		}
-		if (geo.y == usable.y) {
-			offset.y += half_gap;
-			offset.height -= half_gap;
-		}
-		if (geo.x + geo.width == usable.x + usable.width) {
-			offset.width -= half_gap;
-		}
-		if (geo.y + geo.height == usable.y + usable.height) {
-			offset.height -= half_gap;
-		}
-		geo.x += offset.x;
-		geo.y += offset.y;
-		geo.width += offset.width;
-		geo.height += offset.height;
-	}
-
-	/* And adjust for current view */
-	struct border margin = ssd_get_margin(view->ssd);
-	geo.x += margin.left;
-	geo.y += margin.top;
-	geo.width -= margin.left + margin.right;
-	geo.height -= margin.top + margin.bottom;
-
+	struct wlr_box geo = view_get_region_snap_box(view, view->tiled_region);
 	view_move_resize(view, geo);
 }