Add a penalty when getting on and off a train

Fixes #7.

src/dijkstragraph.c

@@ -180,10 +180,7 @@ dijkstra_cost dijkstra_get_weight_from_distance(struct dijkstra_node *node_a,
 
 	switch (net_type) {
 	case TRAINLINE:
-		scale = 5.0;
-		break;
-	case ACCESS:
-		scale = 0.5;
+		scale = 10.0;
 		break;
 	default:
 		scale = 1.0;

src/dijkstrasearch.c

@@ -112,6 +112,11 @@ struct dijkstra_node *dijkstra_search_process_queue(struct dijkstra_search *sear
 	for (l = node->paths; l != NULL; l = l->next) {
 		path = (struct dijkstra_path*) l->data;
 		cost = state->cost + path->weight;
+		if (state->cheapest_path && path->net_meta->type == ACCESS) { // If we just jumped onto an access path
+			if (state->cheapest_path->net_meta->type != ACCESS) {// and we came from a non-access path (getting on or off)
+				cost += (DIJKSTRA_ACCESS_PENALTY * 100.0); // add a penalty
+			}
+		}
 
 		connection = dijkstra_node_get_connection(node, path);
 

src/dijkstrasearch.h

@@ -5,6 +5,8 @@
 
 #define DIJKSTRA_SEARCH_MAX_ITERATIONS 5000
 
+#define DIJKSTRA_ACCESS_PENALTY 300.0
+
 struct dijkstra_state {
 	struct dijkstra_path *cheapest_path;
 	dijkstra_cost cost;