Terrarum/SAVE_FORMAT.md

Format

Contain everything on TEVD

• Save meta

  • binary
  • Filename : world (with no extension)

  Type	Mnemonic	Description
  Byte[4]	TESV	Magic
  Byte[n]	name	Savegame name, UTF-8
  Byte	NULL	String terminator
  Byte[8]	terraseed	Terrain seed
  Byte[8]	rogueseed	Randomiser seed
  Byte[4]	crc1	CRC-32 of worldinfo1 entry
  Byte[4]	crc2	CRC-32 of worldinfo2 entry
  Byte[4]	crc3	CRC-32 of worldinfo3 entry
  Byte[4]	crc4	CRC-32 of worldinfo4 entry
  Byte[32]	hash4321	SHA-256 of crc4..crc3..crc2..crc1
  Int	refid	Reference ID of the player
  Long	time_t	Current world's time_t
  Byte[6]	t_create	Creation time of the savefile in time_t
  Byte[6]	t_lastacc	Last play time in time_t
  Int	t_wasted	Total playtime in time_t

  Endianness: Big

  each entry on the disk contains CRC of its data, we can compare CRC saved in meta && CRC of entry header && CRC of actual content

• Actor/Faction data

  • GSON
  • Filename : (refid) (with no extension)

• Prop data

  • CSV
  • Filename : (with no extension) worldinfo2 -- tileprop worldinfo3 -- itemprop worldinfo4 -- materialprop worldinfo5 -- modules loadorder

• Human-readable

  • Tiles_list.txt -- list of tiles in csv
  • Items_list.txt -- list of items in csv
  • Materials_list.txt -- list of materials in csv
  • load_order.txt -- module load order

How it works

• If hash discrepancy has detected, (hash of csv in save dir != stored hash || hash of TEMD != stored hash), printout "Save file corrupted. Continue?" with prompt "Yes/No"

Directory:

+--- <save1.tevd>
 --- 2a93bc5f (item ID) Actor/DynamicItem/Faction/etc. data (JSON)
 --- 423bdc83 (item ID) Actor/DynamicItem/Faction/etc. data (JSON)
 --- Items_list.txt     Human-readable
 --- Materials_list.txt Human-readable
 --- Tiles_list.txt     Human-readable
 --- world              save meta (binary)
 --- worldinfo1         TEMD (binary)
 --- worldinfo2         tileprop (CSV)
 --- worldinfo3         itemprop (CSV)
 --- worldinfo4         materialprop (CSV)
 +--- computers
  --- (UUID)            virtual disk
 +--- tapestries
  --- (random Int)      tapestry

Alongside with save1.tevd (extension should not exist in real game), keep save1.backup.tevd as a last-working save.