new savegame scheme suggestion

SAVE_FORMAT.md

@@ -1,74 +1,31 @@
-##  Format  ##
+## Introduction ##
 
-Contain everything on [TEVD](github.com/minjaesong/TerranVirtualDisk)
+On the main game, any player can access any generated worlds, and thus players data and worlds are saved separately.
 
-*  Save meta
-    - binary
-    - Filename : world (with no extension)
+The main game directory is composed of following directories:
 
-    |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
+```
+.Terrarum
++ Players
+  - <Player Name Here>, JSON.gz
++ Shared
+  - <e.g. Disk GUID>, TEVD { * }
+  - <this directory can have anything>
++ Worlds
+  - <World Name Here>, TVDA { WriteWorld, actors JSON, chunk data, screenshot.tga.gz taken by the last player }
+```
 
-*  Actor/Faction data
-    - GSON
-    - Filename : (refid) (with no extension)
+(TEVD stands for Terrarum Virtual Disk spec version 3, TVDA stands for spec version 254; both have MAGIC header of `TEVd`)
 
+## Prerequisites ##
 
-*  Prop data
-    - CSV
-    - Filename : (with no extension)
-    worldinfo2 -- tileprop
-    worldinfo3 -- itemprop
-    worldinfo4 -- materialprop
-    worldinfo5 -- modules loadorder
+1. Player ID must not be strictly 9545698 (0x91A7E2)
+    1. Use classname `net.torvald.terrarum.modulebasegame.gameactors.IngamePlayer` to check
+2. Each world has to be uniquely identifiable
+    1. Use GUID, World Name, etc.
+3. `ActorNowPlaying` must be drawn on top of other actors of same RenderOrder
 
+## Goals ##
 
-*  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.
+1. Allows multiple players share same world
+2. Makes multiplayer possible