In this chapter you will learn how a teeworlds map is structured. This knowledge is not necessary for using tml, but it can be helpfull if you are interested in understanding what is going on under the hood or just want to hack a map yourself.
The first bytes just contain the word “DATA” or “ATAD” (little oder big endian), it is the “signature” of a teeworlds map. After that there is an int which contains the version of the mapformat, teeworlds 0.5 uses version 4 but also supports 3, this libary only supports 4.
DATA\\x04\\x00\\x00\\x00
Then there are four more ints which can be read straight from the file. These are “size”, “swaplen”, “num_item_types”, “num_items”, “num_raw_data”, “item_size” and “data_size”.
Now the offsets can be calculated. This is important to seek directly to the items or datas which contain the actual data. The item offset is the sum of the following:
To access the data an additional value gets added to the item offset
After the header the types are stored. For each item type there is a list containing the type, the number of items for this type and which itme is the first for this type. The list is sorted by item type and item id.
Right after the types the item offsets are stored. The first offset is 0. The offset to the next item will be the size of the previous item. The size of each item is as big as defined in mapitems.h (see teeworlds source) plus 2 more integers containing the type, id and the item size.
After the item offsets the data offsets are stored. The first offset is 0. The offset to the next data will be the size of the previous data. The size of each data gets generated when saveing the map.
The uncompressed data sizes are stored after the data offsets. The sizes are used to allocate the memory for each data in teeworlds.
Finally the items are stored. Every item will be stored with all its data in this order:
Every item contains the data as defined in mapitems.h (see teeworlds source) plus 2 more integers containing the type, id and the item size. Type and id is within the first integer. To extract the type and id the following formulas are used:
Eventually the datas are stored. The data is compressed using zlib. Each item which requires data has an index which tells the position of the corresponding data. The compressed data part stores image names, tiles, quads and embedded images.