1 files changed, 90 insertions, 11 deletions

diff --git a/scene/gui/tree.cpp b/scene/gui/tree.cpp
index 2f78736a12..d2b98eb0fa 100644
--- a/scene/gui/tree.cpp
+++ b/scene/gui/tree.cpp
@@ -1184,15 +1184,23 @@ void Tree::update_cache() {
 
 	cache.font_color = get_theme_color("font_color");
 	cache.font_selected_color = get_theme_color("font_selected_color");
-	cache.guide_color = get_theme_color("guide_color");
 	cache.drop_position_color = get_theme_color("drop_position_color");
 	cache.hseparation = get_theme_constant("hseparation");
 	cache.vseparation = get_theme_constant("vseparation");
 	cache.item_margin = get_theme_constant("item_margin");
 	cache.button_margin = get_theme_constant("button_margin");
+
 	cache.draw_guides = get_theme_constant("draw_guides");
+	cache.guide_color = get_theme_color("guide_color");
 	cache.draw_relationship_lines = get_theme_constant("draw_relationship_lines");
+	cache.relationship_line_width = get_theme_constant("relationship_line_width");
+	cache.parent_hl_line_width = get_theme_constant("parent_hl_line_width");
+	cache.children_hl_line_width = get_theme_constant("children_hl_line_width");
+	cache.parent_hl_line_margin = get_theme_constant("parent_hl_line_margin");
 	cache.relationship_line_color = get_theme_color("relationship_line_color");
+	cache.parent_hl_line_color = get_theme_color("parent_hl_line_color");
+	cache.children_hl_line_color = get_theme_color("children_hl_line_color");
+
 	cache.scroll_border = get_theme_constant("scroll_border");
 	cache.scroll_speed = get_theme_constant("scroll_speed");
 
@@ -1813,38 +1821,79 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 
 		TreeItem *c = p_item->first_child;
 
-		int prev_ofs = children_pos.y - cache.offset.y + p_draw_ofs.y;
+		int base_ofs = children_pos.y - cache.offset.y + p_draw_ofs.y;
+		int prev_ofs = base_ofs;
+		int prev_hl_ofs = base_ofs;
 
 		while (c) {
 			if (cache.draw_relationship_lines > 0 && (!hide_root || c->parent != root)) {
 				int root_ofs = children_pos.x + ((p_item->disable_folding || hide_folding) ? cache.hseparation : cache.item_margin);
-				int parent_ofs = p_pos.x + ((p_item->disable_folding || hide_folding) ? cache.hseparation : cache.item_margin);
+				int parent_ofs = p_pos.x + cache.item_margin;
 				Point2i root_pos = Point2i(root_ofs, children_pos.y + label_h / 2) - cache.offset + p_draw_ofs;
 
 				if (c->get_first_child() != nullptr) {
 					root_pos -= Point2i(cache.arrow->get_width(), 0);
 				}
 
-				float line_width = 1.0;
+				float line_width = cache.relationship_line_width;
+				float parent_line_width = cache.parent_hl_line_width;
+				float children_line_width = cache.children_hl_line_width;
+
 #ifdef TOOLS_ENABLED
 				line_width *= Math::round(EDSCALE);
+				parent_line_width *= Math::round(EDSCALE);
+				children_line_width *= Math::round(EDSCALE);
 #endif
 
 				Point2i parent_pos = Point2i(parent_ofs - cache.arrow->get_width() / 2, p_pos.y + label_h / 2 + cache.arrow->get_height() / 2) - cache.offset + p_draw_ofs;
 
+				int more_prev_ofs = 0;
+
 				if (root_pos.y + line_width >= 0) {
 					if (rtl) {
 						root_pos.x = get_size().width - root_pos.x;
 						parent_pos.x = get_size().width - parent_pos.x;
 					}
-					RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x - Math::floor(line_width / 2), root_pos.y), cache.relationship_line_color, line_width);
-					RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y), Point2i(parent_pos.x, prev_ofs), cache.relationship_line_color, line_width);
+
+					// Order of parts on this bend: the horizontal line first, then the vertical line.
+					if (_is_branch_selected(c)) {
+						// If this item or one of its children is selected, we draw the line using parent highlight style.
+						RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x + Math::floor(parent_line_width / 2), root_pos.y), cache.parent_hl_line_color, parent_line_width);
+						RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y + Math::floor(parent_line_width / 2)), Point2i(parent_pos.x, prev_hl_ofs), cache.parent_hl_line_color, parent_line_width);
+
+						more_prev_ofs = cache.parent_hl_line_margin;
+						prev_hl_ofs = root_pos.y + Math::floor(parent_line_width / 2);
+					} else if (p_item->is_selected(0)) {
+						// If parent item is selected (but this item is not), we draw the line using children highlight style.
+						// Siblings of the selected branch can be drawn with a slight offset and their vertical line must appear as highlighted.
+						if (_is_sibling_branch_selected(c)) {
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x + Math::floor(parent_line_width / 2), root_pos.y), cache.children_hl_line_color, children_line_width);
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y + Math::floor(parent_line_width / 2)), Point2i(parent_pos.x, prev_hl_ofs), cache.parent_hl_line_color, parent_line_width);
+
+							prev_hl_ofs = root_pos.y + Math::floor(parent_line_width / 2);
+						} else {
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x + Math::floor(children_line_width / 2), root_pos.y), cache.children_hl_line_color, children_line_width);
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y + Math::floor(children_line_width / 2)), Point2i(parent_pos.x, prev_ofs + Math::floor(children_line_width / 2)), cache.children_hl_line_color, children_line_width);
+						}
+					} else {
+						// If nothing of the above is true, we draw the line using normal style.
+						// Siblings of the selected branch can be drawn with a slight offset and their vertical line must appear as highlighted.
+						if (_is_sibling_branch_selected(c)) {
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x + cache.parent_hl_line_margin, root_pos.y), cache.relationship_line_color, line_width);
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y + Math::floor(parent_line_width / 2)), Point2i(parent_pos.x, prev_hl_ofs), cache.parent_hl_line_color, parent_line_width);
+
+							prev_hl_ofs = root_pos.y + Math::floor(parent_line_width / 2);
+						} else {
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, root_pos, Point2i(parent_pos.x + Math::floor(line_width / 2), root_pos.y), cache.relationship_line_color, line_width);
+							RenderingServer::get_singleton()->canvas_item_add_line(ci, Point2i(parent_pos.x, root_pos.y + Math::floor(line_width / 2)), Point2i(parent_pos.x, prev_ofs + Math::floor(line_width / 2)), cache.relationship_line_color, line_width);
+						}
+					}
 				}
 
 				if (htotal < 0) {
 					return -1;
 				}
-				prev_ofs = root_pos.y;
+				prev_ofs = root_pos.y + more_prev_ofs;
 			}
 
 			if (htotal >= 0) {
@@ -1853,10 +1902,10 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 				if (child_h < 0) {
 					if (cache.draw_relationship_lines == 0) {
 						return -1; // break, stop drawing, no need to anymore
-					} else {
-						htotal = -1;
-						children_pos.y = cache.offset.y + p_draw_size.height;
 					}
+
+					htotal = -1;
+					children_pos.y = cache.offset.y + p_draw_size.height;
 				} else {
 					htotal += child_h;
 					children_pos.y += child_h;
@@ -1889,6 +1938,36 @@ int Tree::_count_selected_items(TreeItem *p_from) const {
 	return count;
 }
 
+bool Tree::_is_branch_selected(TreeItem *p_from) const {
+	for (int i = 0; i < columns.size(); i++) {
+		if (p_from->is_selected(i)) {
+			return true;
+		}
+	}
+
+	TreeItem *child_item = p_from->get_first_child();
+	while (child_item) {
+		if (_is_branch_selected(child_item)) {
+			return true;
+		}
+		child_item = child_item->get_next();
+	}
+
+	return false;
+}
+
+bool Tree::_is_sibling_branch_selected(TreeItem *p_from) const {
+	TreeItem *sibling_item = p_from->get_next();
+	while (sibling_item) {
+		if (_is_branch_selected(sibling_item)) {
+			return true;
+		}
+		sibling_item = sibling_item->get_next();
+	}
+
+	return false;
+}
+
 void Tree::select_single_item(TreeItem *p_selected, TreeItem *p_current, int p_col, TreeItem *p_prev, bool *r_in_range, bool p_force_deselect) {
 	TreeItem::Cell &selected_cell = p_selected->cells.write[p_col];
 
@@ -4386,7 +4465,7 @@ void Tree::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "allow_rmb_select"), "set_allow_rmb_select", "get_allow_rmb_select");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "hide_folding"), "set_hide_folding", "is_folding_hidden");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "hide_root"), "set_hide_root", "is_root_hidden");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "drop_mode_flags", PROPERTY_HINT_FLAGS, "On Item,In between"), "set_drop_mode_flags", "get_drop_mode_flags");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "drop_mode_flags", PROPERTY_HINT_FLAGS, "On Item,In Between"), "set_drop_mode_flags", "get_drop_mode_flags");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "select_mode", PROPERTY_HINT_ENUM, "Single,Row,Multi"), "set_select_mode", "get_select_mode");
 
 	ADD_SIGNAL(MethodInfo("item_selected"));