Enhanced sanity checks.

src/engine/gameManager/BuildingManager.java

@@ -966,8 +966,10 @@ public enum BuildingManager {
 
     public static void bakeNavMesh(Building building) {
 
-        if (building.parentZone == null)
+        if (building.parentZone == null) {
             Logger.error("Attempt to bake navmesh with no parent: " + building.getObjectUUID());
+            return;
+        }
 
         // Build up navmesh by stencil of the
         // convex hull meshes that comprise the prop.
@@ -975,6 +977,11 @@ public enum BuildingManager {
         ArrayList<ArrayList<Vector2f>> convexHullList;
         convexHullList = _hull_data.get(building.meshUUID);
 
+        if (convexHullList == null) {
+            Logger.error("Attempt to bake navmesh with no meshes: " + building.getObjectUUID());
+            return;
+        }
+
         for (ArrayList<Vector2f> meshEntry : convexHullList) {
 
             Path2D.Float stencilPath = new Path2D.Float();