ssd: allow ssd to be smaller than minimal size

With 2603dbf labwc refused to update ssd geometry when its geometry is
smaller than minimal size in order to prevent passing negative values in
wlr_scene_rect_set_size(), but it made ssd for small windows like
workrave ugly. So this commit fixes the negative values for each call to
wlr_scene_rect_set_size() individually rather than just early-return in
ssd_update_geometry().

Co-Authored-By: Consolatis <35009135+Consolatis@users.noreply.github.com>

include/ssd-internal.h

@@ -59,6 +59,8 @@ struct ssd {
 		} title;
 	} state;
 
+	struct wlr_scene_rect *view_background;
+
 	/* An invisible area around the view which allows resizing */
 	struct ssd_sub_tree extents;
 

src/ssd/ssd-border.c

@@ -82,7 +82,7 @@ ssd_border_update(struct ssd *ssd)
 
 	struct theme *theme = view->server->theme;
 
-	int width = view->current.width;
+	int width = MAX(view->current.width, LAB_MIN_VIEW_WIDTH);
 	int height = view_effective_height(view, /* use_pending */ false);
 	int full_width = width + 2 * theme->border_width;
 

src/ssd/ssd-extents.c

@@ -104,7 +104,7 @@ ssd_extents_update(struct ssd *ssd)
 
 	struct theme *theme = view->server->theme;
 
-	int width = view->current.width;
+	int width = MAX(view->current.width, LAB_MIN_VIEW_WIDTH);
 	int height = view_effective_height(view, /* use_pending */ false);
 	int full_height = height + theme->border_width * 2 + ssd->titlebar.height;
 	int full_width = width + 2 * theme->border_width;

src/ssd/ssd-shadow.c

@@ -169,7 +169,7 @@ set_shadow_geometry(struct ssd *ssd)
 	struct view *view = ssd->view;
 	struct theme *theme = view->server->theme;
 	int titlebar_height = ssd->titlebar.height;
-	int width = view->current.width;
+	int width = MAX(view->current.width, LAB_MIN_VIEW_WIDTH);
 	int height = view_effective_height(view, false) + titlebar_height;
 
 	struct ssd_part *part;

src/ssd/ssd-titlebar.c

@@ -210,6 +210,8 @@ ssd_titlebar_update(struct ssd *ssd)
 		return;
 	}
 
+	int title_bar_width = MAX(0, width - SSD_BUTTON_WIDTH * SSD_BUTTON_COUNT);
+
 	struct ssd_part *part;
 	struct ssd_sub_tree *subtree;
 	FOR_EACH_STATE(ssd, subtree) {
@@ -218,25 +220,25 @@ ssd_titlebar_update(struct ssd *ssd)
 			case LAB_SSD_PART_TITLEBAR:
 				wlr_scene_rect_set_size(
 					wlr_scene_rect_from_node(part->node),
-					width - SSD_BUTTON_WIDTH * SSD_BUTTON_COUNT,
+					title_bar_width,
 					theme->title_height);
 				continue;
 			case LAB_SSD_BUTTON_ICONIFY:
 				if (is_direct_child(part->node, subtree)) {
 					wlr_scene_node_set_position(part->node,
-						width - SSD_BUTTON_WIDTH * 3, 0);
+						title_bar_width + 1 * SSD_BUTTON_WIDTH, 0);
 				}
 				continue;
 			case LAB_SSD_BUTTON_MAXIMIZE:
 				if (is_direct_child(part->node, subtree)) {
 					wlr_scene_node_set_position(part->node,
-						width - SSD_BUTTON_WIDTH * 2, 0);
+						title_bar_width + 2 * SSD_BUTTON_WIDTH, 0);
 				}
 				continue;
 			case LAB_SSD_PART_CORNER_TOP_RIGHT:
 				if (is_direct_child(part->node, subtree)) {
 					wlr_scene_node_set_position(part->node,
-						width - SSD_BUTTON_WIDTH * 1, 0);
+						title_bar_width + 3 * SSD_BUTTON_WIDTH, 0);
 				}
 				continue;
 			default:

src/ssd/ssd.c

@@ -138,6 +138,11 @@ ssd_get_part_type(const struct ssd *ssd, struct wlr_scene_node *node)
 			}
 		}
 	}
+
+	if (ssd->view_background && node == &ssd->view_background->node) {
+		return LAB_SSD_CLIENT;
+	}
+
 	return LAB_SSD_NONE;
 }
 
@@ -230,16 +235,6 @@ ssd_update_geometry(struct ssd *ssd)
 	int eff_width = current.width;
 	int eff_height = view_effective_height(ssd->view, /* use_pending */ false);
 
-	if (eff_width > 0 && eff_width < LAB_MIN_VIEW_WIDTH) {
-		/*
-		 * Prevent negative values in calculations like
-		 * `width - SSD_BUTTON_WIDTH * SSD_BUTTON_COUNT`
-		 */
-		wlr_log(WLR_ERROR,
-			"view width is smaller than its minimal value");
-		return;
-	}
-
 	if (eff_width == cached.width && eff_height == cached.height) {
 		if (current.x != cached.x || current.y != cached.y) {
 			/* Dynamically resize extents based on position and usable_area */
@@ -267,6 +262,25 @@ ssd_update_geometry(struct ssd *ssd)
 		}
 		return;
 	}
+
+	if (current.width < LAB_MIN_VIEW_WIDTH) {
+		/*
+		 * This draws a border-colored background behind the
+		 * view for poorly behaving clients that don't follow
+		 * our requested minimal size.
+		 */
+		if (!ssd->view_background) {
+			ssd->view_background = wlr_scene_rect_create(ssd->tree, 0, 0,
+				ssd->view == ssd->view->server->active_view
+					? rc.theme->window_active_border_color
+					: rc.theme->window_inactive_border_color);
+		}
+		wlr_scene_rect_set_size(ssd->view_background, LAB_MIN_VIEW_WIDTH, current.height);
+		wlr_scene_node_set_enabled(&ssd->view_background->node, true);
+	} else if (ssd->view_background) {
+		wlr_scene_node_set_enabled(&ssd->view_background->node, false);
+	}
+
 	ssd_extents_update(ssd);
 	ssd_titlebar_update(ssd);
 	ssd_border_update(ssd);
@@ -385,6 +399,11 @@ ssd_set_active(struct ssd *ssd, bool active)
 		wlr_scene_node_set_enabled(
 			&ssd->shadow.inactive.tree->node, !active);
 	}
+	if (ssd->view_background) {
+		wlr_scene_rect_set_color(ssd->view_background, active
+			? rc.theme->window_active_border_color
+			: rc.theme->window_inactive_border_color);
+	}
 }
 
 void
@@ -465,5 +484,17 @@ ssd_debug_get_node_name(const struct ssd *ssd, struct wlr_scene_node *node)
 	if (node == &ssd->extents.tree->node) {
 		return "extents";
 	}
+
+	/* These are only created on demand */
+	if (ssd->shadow.active.tree && node == &ssd->shadow.active.tree->node) {
+		return "shadow.active";
+	}
+	if (ssd->shadow.inactive.tree && node == &ssd->shadow.inactive.tree->node) {
+		return "shadow.inactive";
+	}
+	if (ssd->view_background && node == &ssd->view_background->node) {
+		return "view_background";
+	}
+
 	return NULL;
 }