View difference between Paste ID: FMg98wU0 and 6FLRBhcq

 local sprite = require "sprite"
 
 local createMap(self, size, columns, rows)
         local map = display.newGroup()
         map.Tiles = {}
         for row=0,rows+1 do
                 map.Tiles[row] = {}
                 for column=0,columns+1 do
                         local tile = sprite.newSprite(self)
                         tile:setReferencePoint(display.BottomLeftReferencePoint)
                         map:insert(tile)
                         tile.xScale, tile.yScale = size / tile.width, size / tile.height
                         tile.x, tile.y = column * size, row * size
                         map.Tiles[row][column] = tile
                 end
         end
         return map
 end
 
-return function(spritesheet, size, kinds)
+return function(spritesheet, size, kinds, mapping)
 	if not mapping then
 		for _, kind in ipairs(kinds) do
 			mapping[kinds:sub(1, 1):upper()] = kinds
 		end
 	end
 	local terrain = sprite.newSpriteSet(sprite.newSpriteSheet(spritesheet, 	size, size), 1, 1)
 	for i, kind in ipairs(kinds) do
 		sprite.add(terrain, kind, i + 1, 1, 1, 1)
 	end
 	terrain.Create = createMap
 	terrain.Mapping = mapping
 	return terrain
 end