DISC 8 ROOM CITADEL REASSEMBLY
0.1-d8r-r1
19th December 2021
"Diminished"

This is a version of the Citadel Reassembly, tweaked for the playable 
demonstration and further refinement of the antique map generator (ROOM) from 
Disc 8 of Michael Jakobsen's floppies.

See the added disc8ROOM-assets directory in this package for the source 
materials that were used to modify this copy.
 
The following changes have been made to a vanilla copy of the Citadel 
Reassembly (v0.1):
 
- Patches to the game engine (citadel.asm), as follows:

  - D_CHEAT_INVINCIBLE and D_CHEAT_UNLOCK_DOORS are set to 1, to make it easier 
    to get around the map;
  - the routines responsible for solving puzzles have been patched out;
  - code to place both items and energy flasks into rooms has been patched out, 
    since no information on item or flask locations is available for this 
    version of the map;
  - code to overlay the title screen text has been patched out, since this 
    map is not believed to contain a title screen;
  - the item pad has had its ID changed in the engine from 6 to 0.
    
  These modifications have hopefully been performed in a manner that does not 
  change the assembled addresses of anything, so pokes and patches intended to 
  be applied against the Beeb retail version should mostly work here too.

- The data blob x740.bin in this package has been generated by concatenating 
  three provided files (see disc8ROOM-assets/x740-components):
  
  ( x740-1-header.bin + x740-2-figs-pad.bin + x740-3-D.ROOM.bin )
  
  - x740-1-header.bin is the first 533 bytes of x740.bin from the retail 
    release;
  - x740-2-figs-pad.bin is a custom figures file built using the sprite 
    information contained in the Disc 8 ROOM file;
  - x740-3-D.ROOM.bin is the D.ROOM file that was generated by the Disc 8 ROOM 
    (with some modifications and simplifications, to prevent it crashing the 
    game engine).
    
Two modified versions of the Disc 8 ROOM itself (a BASIC program) are included 
here:

- disc8ROOM-assets/disc8ROOM-patched-BASIC/ROOM-d2+d8-try1.txt

  This is a minimally-patched copy of ROOM, which runs in BASIC without 
  error, but ten of the rooms will crash the retail engine when loaded.

- disc8ROOM-assets/disc8ROOM-patched-BASIC/ROOM-d2+d8-try3.txt

  A minimum of BASIC code has been removed from -try1 in order to produce a 
  D.ROOM that does not crash the retail engine. This is the precise version 
  used to make the bundled x740.bin. 
    
-try3 is clearly imperfect and requires further work. It is hoped that such 
improvements to the Disc 8 ROOM will not necessitate changing either the header 
or the figure data. Revised generations of D.ROOM can hopefully be dropped in as 
x740-3-D.ROOM.bin, and a new x740.bin simply pasted together (e.g. with "cat") 
for testing.

The set of figure files that were concatenated to make x740-2-figs-pad.bin has 
also been bundled as disc8ROOM-assets/figs/* for completeness. Note that 
these must be padded out (e.g. with zeros) to 2,635 bytes after concatenation. 
However, it is hoped that the included x740-2-figs-pad.bin is close enough to the 
intended configuration that rebuilding it should not be necessary.

Have fun!