2D Path Builder

Hi All,
I want to crate a racing game which allows the player to build his own path or track and then race on that track with other opponents. How can I add this functionality of building their own path during play time ?

 

Sorry but I think your question is a little too open ended to really be able to give a meaningful reply. Personally, I'd get the racing part working well first and then worry about an in game track builder for it.

 

I have already made the racing game.... it is just that in game track builder functionality is left in the game

 

I guess the same way you built the race track...you need to build an interface or an import functionality (if its designed in another program)