1 files changed, 39 insertions, 0 deletions
diff --git a/src/group_cmd.cpp b/src/group_cmd.cpp
index 1dfa8e258..d4148474f 100644
--- a/src/group_cmd.cpp
+++ b/src/group_cmd.cpp
@@ -54,6 +54,45 @@ void GroupStatistics::Clear()
 	this->num_engines = CallocT<uint16>(Engine::GetPoolSize());
 }
 
+/**
+ * Update all caches after loading a game, changing NewGRF etc..
+ */
+/* static */ void GroupStatistics::UpdateAfterLoad()
+{
+	size_t engines = Engine::GetPoolSize();
+
+	/* Set up the engine count for all companies */
+	Company *c;
+	FOR_ALL_COMPANIES(c) {
+		free(c->num_engines);
+		c->num_engines = CallocT<EngineID>(engines);
+	}
+
+	/* Recalculate */
+	Group *g;
+	FOR_ALL_GROUPS(g) {
+		g->statistics.Clear();
+	}
+
+	const Vehicle *v;
+	FOR_ALL_VEHICLES(v) {
+		if (!v->IsEngineCountable()) continue;
+
+		assert(v->engine_type < engines);
+
+		Company::Get(v->owner)->num_engines[v->engine_type]++;
+
+		if (v->group_id == DEFAULT_GROUP) continue;
+
+		g = Group::Get(v->group_id);
+		assert(v->type == g->vehicle_type);
+		assert(v->owner == g->owner);
+
+		g->statistics.num_engines[v->engine_type]++;
+		if (v->IsPrimaryVehicle()) g->statistics.num_vehicle++;
+	}
+}
+
 
 /**
  * Update the num engines of a groupID. Decrease the old one and increase the new one