how to color waypoints or the directions polyline in v3 google map direction service

I am using gmap v3 direction service. I am us开发者_JAVA百科ing waypoints. I am displaying three routes and i want all the three routes to be in different color. how to change the color of the routes?

All the routes are using PolyLines, and you can set the color by passing them a http://code.google.com/apis/maps/documentation/javascript/reference.html#PolylineOptions

The only problem is that each DirectionRenderer can only have one type of PolyLines, so you need to have more than one DirectionRenderer as far as I can understand, and I am not sure how they will work together if you try to display them on the same map.