Tuesday 29 April 2014

Tim Hartnell's "Chateau Gaillard"


I found the source code for this on an Atari site that has archived a whole bunch of published materials for early 8-bit computers. There seems to be something about the Atari crowd that inclines them to programming activities. Their collective efforts to support this inclination are also helpful for the rest of us 8-biters. One interesting book they have maintained in digital form is Tim Hartnell's classic Creating Adventure Games on Your Computer. In the course of porting "Chateau Gaillard" to the TRS-80 MC-10, I found a few errors in the original listing. For example, the way the code originally worked the weapon you chose seemed to have no effect on combat. There were elaborate routines for reporting and selecting which weapon you would use, but when it came right down to it, the value entered was not used in the combat routine. There were also some other bugs, such as the interaction with the Dwarf (misreported the objects he was willing to accept during negotiations) and the fact that you could simply "go up" back to the surface from the initial room you fall into, contrary to the message that "there is now no way back." On the whole, the combat routine just seemed overly punishing and I found the game difficult to complete, so I adjusted it. Also, when you moved an excessive number of points were randomly subtracted from your statistics. I changed it so that only your strength is randomly diminished as you explore, and at a much lower rate. Now you at least have a chance of finding the healing potion and replenishing your strength. I also added a routine to allow you to re-roll your character stats at the beginning of the game until you get a reasonably fair dispersal. As with most Basic two-word parsers there are some quirks. There is no shorthand N, S, E, or W for moving. The closest you can get is GO N, GO S, etc. Otherwise, three letters is all you need for either word to register. However, I added a single word "INVENTORY" command, because I didn’t like seeing an inventory automatically with every new screen. There are lots of arbitrary deaths in this game from traps, so you’ll just have to play it multiple times and map it enough to learn where not to go. That being said, some meager clues are given to help you avoid some of these deaths. The basic object of the game is to find the two keys, which are needed to allow you to escape two rooms that otherwise lock you in. Once you get the right keys for the right rooms, you can use them to unlock all the doors in those rooms, which will allow you to find a stairwell back to the surface. On the whole, it is a fun little 8-bit Basic dungeon romp. The combat routine is quite unique in the way it allows you to choose which vital statistics you will draw on in your combat against the different creatures (which have some very creative names) and their distinctive vital stats. In brief you should try to select your highest stats while selecting the lowest equivalent stats of your opponent. Various clues about how to overcome dangers are also sprinkled throughout the maze, which is a nice touch. If you get stuck there is a map below to give you a hand. The coordinated colors indicate various rooms with ways to move up or down between the levels.

** SPOILER ALERT **

Above Ground 



Chateau Forest
(Start)
Escape


Level 2







Smokey Room
Cursed Mirror
Marble Room








Cramped Room
(Start)
Mirrored Hall






Draped Hall
Dwarf’s
Room
Long Corridor





Spider
Alcove

Despair
Room
Game Room



Silver Key



Stone Cavern

Dried Fountain
Dried Flowers

Battle- ments
Eerie Room
Mattress Room
Paneled Room
Stone Trap


Potting Shed



Trap
Kitchen
Black Dragon





Flaming
Pit
L Shaped
Room
Arch


Landing







Fresh Air









Level 3

Slippery Room
Torture Chamber
Dungeon
Gargoyle

Dingy Pit
Dance Hall
Gloomy Passage





Common Hovel
Trophy Room
Rear Turret
Gold Key


Cobweb Room
Secret Room



Tuesday 22 April 2014

Citadelle: The Shield of Oran

In the first installment of Loriciels' Citadelle series, which I ported from source code from the Sanyo PHC-25, and translated to English, you will come up against a range of monsters. There are Lich’s, Bugbears, Orcs, Assassins, Warriors, Shades and Gnolls. The game feels like an RPG, but it actually combines elements of that genre with a simple two-word parser text adventure and treasure hunt. There are puzzles to be solved too.

In the version I ported the stats of the monsters are randomly generated in terms of the hit points, armour class and strength at the beginning of each combat, so retreating might not be a good idea. Retreating takes you back to the previous room you were in. When you re-enter the room all the conditions for the monster will be reset. This might be a good thing if the monster is really strong and you’re getting pasted. Going and coming back in might make for a weaker monster. However, it might be worse!

Choosing Defence rather than attack just reduces your chances of being hit while also decreasing your chances of hitting the monster. Spells are powerful but fickle. The monsters are deployed in fixed locations as indicated in the map below.  However, if they don’t “disappear” at the end of combat random monsters will be spawned at random in one of the rooms. If you have the sword and the armour, the monsters are pretty easy to defeat. You won’t be let through the portcullis if you get pasted by the Gnoll and you don’t have at least one of these two items. A map and instructions follow:

** SPOILER ALERT ** Walkthrough Map below!



Exit




            N
     W    +    E
            S
      

Tomb

SAY AROG
GIVE EYE
warrior

Arms of Oran

(must have
Lighted lamp)
EXAMINE OBJECT
TAKE SHIELD
EXAMINE SHIELD
harpy
Well Room

SEARCH WELL
TAKE KEY
EXAMINE STONES
OPEN STONE
(requires hammer
 and chisel)
SEARCH NOOK
TAKE EYE
Assassin
Armoury

EXAMINE MOSAICS
EXAMINE STARS
OPEN STAR
(requires hammer
 and chisel)
TAKE ROD
Lich
Tiled Entry Hall

TAKE LAMP
LIGHT LAMP
OPEN DOOR
(requires key)

Dark Hall

EXAMINE FLOOR
SEARCH DUST
EXAMINE WALLS
SEARCH WALLS
USE MECHANISM
Store Room

OPEN CRATES
EMPTY CRATES
(you'll discover
the name Arog)
OPEN BARREL
EMPTY BARRELS
SEARCH SACKS
TAKE CUBE
INSERT CUBE
(requires mech
from dark hall
to have been
touched)

Stables

CLIMB LADDER
SEARCH ROOM
MOVE BOARDS

Inside Cave

SEARCH SKELETON
TAKE CHISEL

Guard Room

USE MECHANISM
Bugbear


Hay Loft

SEARCH SACKS
TAKE HAMMER
SEARCH HAY
DESCEND LADDER
Shadow
In front of Cave

EXAMINE GROUND
TAKE FLINT
TOUCH PORTCULLIS
Gnoll




Forest

MOVE ROCK
TAKE SWORD
SEARCH TREE
TAKE ARMOUR





Sunday 13 April 2014

The Demon’s Eye: Walkthrough Map

I ported this adventure from Coco basic.  It was a type-in program from one of the Color Computer magazines.  I don't recall it being very difficult to port.  Probably just had to get rid of some of the "ELSE" statements and replace them with alternative "IF" logic.

** SPOILER ALERT **



Tuesday 8 April 2014

The Cavern of the Morlocks: Beware the Carrrots Hommeaux!

Cavern of the Morlocks

This classic French text adventure, now translated to English, is unique in several ways. First, its design permits multiple narrative pathways to the completion of the adventure (despite the limits imposed on these possibilities by the 8-bit machine hardware it was developed on--the Matra-Hachette 'Alice' computer). Second, its single key entry decision and navigation system is a interesting departure from the much more standard two word parser system, and is very appropriate for its multiple attempt variable ending play format. Third, it is based (very roughly) on a classic work of fiction. Although its single keystroke system is somewhat similar to other extremely simple early Basic text adventures, the number of rooms, the multiplicity of narrative arches (in which randomness, decisions and the objects and paths selected make a substantial difference), and the playful and well crafted scenarios make for quite an enjoyable hour or so of distraction. Although a game like this will be of no interest to hard core modern players of interactive fiction, it certainly will be of interest to those curious about early 8-bit computer systems and the Basic programming efforts of coders grappling with the inherent limitations of such systems.

My English Language MC-10 Port from the Alice
The Alice was a French introductory computer system somewhat akin to the Sinclair ZX-81 or even the Spectrum, which shared some hardware elements with the TRS-80 Micro Color Computer from Tandy, upon which it was based. I ported and translated the game from the original Alice program by François Coulon.

In the course of porting it I also fixed a few discrepancies in the walls between rooms.  For example, in the "bear" room you were allowed to go West into the Cook's room, but you couldn't go the other direction.  When debugging I used the following "super cheat" code.  Just hit the break key and snip and use the special paste" function in the emulator.  Then type CONT and hit ENTER.

CO=1:BI=1:TR=1:MR=1:AI=1:ME=1:MI=1:GO=1:ST=1:SB=1:CQ=1:CS=1:DI=1

** SPOILER ALERT **

Below is the layout of the dungeon.  The "Y" and "N"s after each room title tell you how to respond to the question.  I'll leave it up to you to figure out the objects you come across.

Thanks to auraes over on the SolutionArchive.com for the maze layout