This should work, too.

Anyway, when you create an own datastructure for your map, your actors have actually access to the map data. You can for instance create a 2-dimensional pointer array with size M x N. Each pointer points to an instance of a block structure in which you could define the type (floor, wall,...), contents (nothing, gold, silver, water,...), texture type (solid rock, earth, ...) and other stuff.

In the end you have to test it out if it works for you in a hurry -- and in the long run.