Fixed the issue of newly built intersecting node not connecting to all existing (intersecting) roads

src/infrastructure/road.zig

@@ -87,6 +87,8 @@ pub const Road = struct {
             if (self.nodes[i] != old_node) continue;
 
             self.nodes[i] = new_node;
+            // As nodes change, road's length must be recalculated
+            self.length = ut.calculate_length(self.nodes[0].pos, self.nodes[1].pos);
             return;
         }
 

src/infrastructure/road_manager.zig

@@ -37,9 +37,8 @@ pub const RoadManager = struct {
     /// Function which creates the road object, its pointer, adds it to the list
     /// and then also references that same road to the bounding nodes
     pub fn addRoad(self: *RoadManager, allocator: std.mem.Allocator, start: *Node, end: *Node) !void {
-        const road: Road = .init(self.getNextID(), start, end);
         const road_ptr = try allocator.create(Road);
-        road_ptr.* = road;
+        road_ptr.* = Road.init(self.getNextID(), start, end);
         try self.roads.append(allocator, road_ptr);
 
         const ref = self.roads.items[self.roads.items.len - 1];

src/simulator.zig

@@ -153,11 +153,6 @@ pub const Simulator = struct {
             // Prevents the road from being attached to 2 identical nodes (0 length road)
             if (temp.id == cur_node.id) return;
 
-            // TODO replace with road splitting
-            self.road_man.addRoad(self.allocator, temp, cur_node) catch |err| {
-                std.debug.panic("Failed to add a new road or assigning its nodes: {}\n", .{err});
-            };
-
             const intersections = self.getIntersectingRoads(self.allocator, temp, cur_node) catch |err| {
                 std.debug.panic("Intersection selection failure: {}\n", .{err});
             };
@@ -170,6 +165,8 @@ pub const Simulator = struct {
                 std.debug.print("Road ID={d} Pos: ({d}, {d})\n", .{int.road.id, int.pos.x, int.pos.y});
             }
 
+            self.splitRoadsByIntersections(intersections, temp, cur_node);
+
             self.node_man.temp_node = if (self.auto_continue) cur_node else null;
             return;
         }
@@ -290,7 +287,7 @@ pub const Simulator = struct {
     /// Takes the data about intersections and adds new nodes there alongside with linking existing roads to them
     ///
     /// Important: This function assumes the intersection array is sorted by distance from the start node (ascending)
-    fn splitRoadsByIntersections(self: *Simulator, intersections: []st.IntersectionData, start: *Node, end: *Node) !void {
+    fn splitRoadsByIntersections(self: *Simulator, intersections: []st.IntersectionData, start: *Node, end: *Node) void {
         if (intersections.len == 0) {
             self.road_man.addRoad(self.allocator, start, end) catch |err| {
                 std.debug.panic("Failed creating the road out of origin nodes: {}\n", .{err});
@@ -329,10 +326,17 @@ pub const Simulator = struct {
             intersection.road.updateNodeReference(old_node_of_road, new_node) catch |err| {
                 std.debug.panic("Failed to update the road's node references: {}\n", .{err});
             };
+            // Now the old node must not point at the intersection road
+            old_node_of_road.unreferenceRoad(intersection.road) catch |err| {
+                std.debug.panic("Failed to unreference the intersection road from the old node: {}\n", .{err});
+            };
+            new_node.referenceRoad(self.allocator, intersection.road) catch |err| {
+                std.debug.panic("Failed to reference the intersection road to the intersecting node: {}\n", .{err});
+            };
 
             // Now we add the road (to the road list) and references the road at both bounding nodes
             self.road_man.addRoad(self.allocator, new_node, old_node_of_road) catch |err| {
-                std.debug.panic("Failed to create a road of new node and former node of prior intersecting road", .{
+                std.debug.panic("Failed to create a road of new node and former node of prior intersecting road: {}\n", .{
                     err
                 });
             };