Technical Documentation - Dungeon Master II Graphics.dat: How to read a directory entry
Author of this documentation: Kentaro.k-21
It will be simple to read.
I took the 1st raw data from dm2 amiga graphics.dat.
ADDRESS 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 0123456789ABCDEF
-------------------------------------------------------------------------
0000000 80 01 27 3D 00 07 54 01 49 01 44 01 53 01 46 01 ..'=..T.I.D.S.F.
0000010 47 01 50 02 00 00 08 00 00 00 00 01 00 00 0B 00 G.P.............
0000020 00 00 00 2B 00 01 00 00 00 FE 00 02 01 00 04 00 ...+............
0000030 00 00 00 F3 01 00 05 06 10 00 00 F8 01 00 05 06 ................
The 1st highlighted word value (27 3D) represents how many entries exist in this binary.
Read this value as a big endian word value even if the target platform is oriented in little endian.
In this case, the value is obtained with expression 0x27 * 256 + 0x3D.
It is 10045. There are 10045 entries in dm2 amiga graphics.dat.
The offset of 1st entry begins at 0x00000014.
Each entry has 8 bytes long.
Next table shows known spec information with 1st entry
00000014: 00 00 08 00 00 00 00 01
| Position | Binary | Known meaning |
|---|---|---|
| 1st byte | 00 | Main Category. One of following values. 0x00: Unknown 0x01: Unknown (for Graphical Interface?) 0x02: No applicable data 0x03: Unknown (Text message in scrolls and message board?) 0x04: No applicable data 0x05: Unknown 0x06: Unknown 0x07: Unknown (for Graphical Interface in inventory window?) 0x08: Unknown (for wall and tile images?) 0x09: Unknown (for Wall Graphics used in dungeon.dat?) 0x0A: Unknown (for Pad Graphics used in dungeon.dat?) 0x0B: Unknown (for Ornate Graphics used in dungeon.dat?) 0x0C: Unknown 0x0D: Unknown (for magical effect images?) 0x0E: Door entry 0x0F: Creature entry 0x10: Weapon entry 0x11: Cloth entry 0x12: Scroll entry 0x13: Potion entry 0x14: Chest entry (contains magical minion maps) 0x15: Miscellaneous item entry 0x16: Hero entry 0x17: Unknown (for weather images?) 0x18: Unknown 0x19: No applicable data 0x1A: Dialogue Interface |
| 2nd byte | 00 | Data index in Main Category. |
| 3rd byte | 08 | Data representation. One of following values. 0x01: Images 0x05: Text Other: Unknown |
| 4th byte | 00 | Depending on what kind of "Data representation". |
| 5th byte | 00 | Depending on what kind of "Data representation". |
| 6th byte | 00 | Depending on what kind of "Data representation". |
| 7th and 8th byte | 00 01 | This entry may store the binary index in graphics.dat to represent data. *If this represents the binary index, it is always stored in big endian format. Depending on what kind of "Data representation". 0x01: The value indicates an index to stored image. 0x05: The value indicates an index to stored text. Other: Unknown |
This is a sample for image entry.
0001313C: 1A 00 01 00 00 FF 00 11
| Position | Binary | Meaning |
|---|---|---|
| 1st byte | 1A | Main Category. |
| 2nd byte | 00 | Index in Main Category. |
| 3rd byte | 01 | It represents an image. |
| 4th byte | 00 | - |
| 5th byte | 00 | - |
| 6th byte | FE | - |
| 7th and 8th byte | 00 11 | 0x00 * 256 + 0x11 = 17. 17th raw data (0 based index) has an image for this entry. |
This is a sample for text entry.
0001315C: 1A 00 05 14 10 FF 00 12
| Position | Binary | Meaning |
|---|---|---|
| 1st byte | 1A | Main Category. |
| 2nd byte | 00 | Index in Main Category. |
| 3rd byte | 05 | It represents a text. |
| 4th byte | 14 | - |
| 5th byte | 10 | - |
| 6th byte | FF | - |
| 7th and 8th byte | 00 12 | 0x00 * 256 + 0x12 = 18. 18th raw data (0 based index) has a text for this entry. |