Fix error when picking up a node with deprecated tile definition (#40)

If `image` instead of `tile` was used, the mod passed nil to minetest.inventorycube.
The color field of a tile is now also supported (the code is used only for the particle image calculation).

init.lua

@@ -93,6 +93,27 @@ if legacy_setting_getbool("item_drop.enable_item_pickup",
 		flowingliquid = true,
 	}
 
+	-- Get an image string from a tile definition
+	local function tile_to_image(tile, fallback_image)
+		if not tile then
+			return fallback_image
+		end
+		local tile_type = type(tile)
+		if tile_type == "string" then
+			return tile
+		end
+		assert(tile_type == "table", "Tile definition is not a string or table")
+		local image = tile.name or tile.image
+		assert(image, "Tile definition has no image file specified")
+		if tile.color then
+			local colorstr = minetest.colorspec_to_colorstring(tile.color)
+			if colorstr then
+				return image .. "^[multiply:" .. colorstr
+			end
+		end
+		return image
+	end
+
 	-- adds the item to the inventory and removes the object
 	local function collect_item(ent, pos, player)
 		item_drop.before_collect(ent, pos, player)
@@ -107,20 +128,11 @@ if legacy_setting_getbool("item_drop.enable_item_pickup",
 			if item and item.tiles and item.tiles[1] then
 				if inventorycube_drawtypes[item.drawtype] then
 					local tiles = item.tiles
-
+					-- color in the tile definition is handled by tile_to_image.
-					local top = tiles[1]
+					-- color in the node definition is not yet supported here.
-					if type(top) == "table" then
+					local top = tile_to_image(tiles[1])
-						top = top.name
+					local left = tile_to_image(tiles[3], top)
-					end
+					local right = tile_to_image(tiles[5], left)
-					local left = tiles[3] or top
-					if type(left) == "table" then
-						left = left.name
-					end
-					local right = tiles[5] or left
-					if type(right) == "table" then
-						right = right.name
-					end
-
 					image = minetest.inventorycube(top, left, right)
 				else
 					image = item.inventory_image or item.tiles[1]
@@ -412,29 +424,13 @@ and not minetest.settings:get_bool("creative_mode") then
 			end
 		end
 	end
-
-	local function pickup_step()
-		local got_item
-		local players = minetest.get_connected_players()
-		for i = 1,#players do
-			got_item = got_item or pickupfunc(players[i])
-		end
-		-- lower step if takeable item(s) were found
-		local time
-		if got_item then
-			time = 0.02
-		else
-			time = 0.2
-		end
-		minetest.after(time, pickup_step)
-	end
-	minetest.after(3.0, pickup_step)
 end
 
+
 local time = (minetest.get_us_time() - load_time_start) / 1000000
 local msg = "[item_drop] loaded after ca. " .. time .. " seconds."
 if time > 0.01 then
 	print(msg)
 else
-	minetest.log("action", msg)
+	minetest.log("info", msg)
 end