def gridForType(cls,x,y,width,gridType):
if Void.isVoidType(gridType):
return Void(x,y,width,gridType)
if Dot.isDotType(gridType):
return Dot(x,y,width,gridType)
if Wall.isWallType(gridType):
return Wall(x,y,width,gridType)
raise ValueError("unknown grid type %s" % (gridType))
