Unfinished Text Adventures

[lurkio]

Hi lurkio, I've encountered another location error having finally managed to get past the Angel of Death. Could you do your fix routine again please:
Satan-Loc-Error.jpg
I presume there's enough info in the screen grab above for you to do so?

I’ll have a look later. Can’t remember if that’s enough info! Can u let me have a walkthrough up to that point?

[fuzzel]

Thanks. I'm on it...
EDIT: Here's the walkthrough to the error.

Code: Select all

W
W
N
E
GET TORCH
N
E
E
E
S
S
U
U
GET MASK
D
D
N
N
N
N
GET MATCHES
S
W
S
S
W
N
W
S 
W
W
GET BATTERY
FIT BATTERY
E
N
N
W
N
W
S
W
N
W
S
GIVE MATCHES
GET PAPER
S
TORCH ON
D
E
S
W
GET CROWBAR
E
E
N
WEAR MASK
N
D
D

An alternative is to "teleport" to the location with the same objects as follows. Using your hacked version at the start:
HIT ESCAPE
Type - O$="4219352723"
(O$ stores the objects carried where each object is a two byte code - see lines 2090 onwards for each object's number). An interesting alternative way of storing inventory objects. Also, if you look at D$ at each location, the first five bytes are the location code then each subsequent pair of digits are the numbers of the objects stored in that location.
Type - E%=3:S%=2:T%=2:G.13
This returns to the program at the above location. Then TORCH ON, LOOK, N, WEAR MASK, N, D, D

[fuzzel]

I've been looking through lurkio's location text from the large data file, Locdata, and comparing it to the locations I've visited so far. It looks as though the one area I haven't been able to explore is the chamber with gallery section and I'm hoping that lurkio's fix will allow access to them. The alternative is that they can be visited by solving the maze at E%:5 S%:5 T%:0 (You are somewhat dazed after falling into a void.) I can't for the life of me work out how to escape from this at present.
I've also had a look at some of the message data in the main program. Although it's compressed it's still quite readable - to read it properly you just call PROCp("message"). I mentioned earlier that I thought there was a bug with the READ command where there was no message when you try to READ BOOK or READ PAPER. I think I've found these messages:
4800DATABelieveInOnlyHalfOfWhatYouRead46whenRunicSymbolsMergeThenWill10ObviousBecomeClear!
4802DATA50paperHas90scrawledOnIt!
I also think I've spotted the bug at line 28 (there's an OSCLI in there):
28IFW%=0PROCqELSEIFj=4PRINTQ$+$&BC9:PRINTQ$+$&B9F:GOTO48925OSCLIRESTORE(4800+j):READP$:PROCp(P$)
If someone can fix this line I'd be very grateful!

[lurkio]

Here's the walkthrough to the error.

Not sure if this was the right thing to do but because a further newly revealed room started erroring once I'd fixed the room you led me to in the walkthrough, I've now hacked the program so that it traps all room numbers less than 18 where T%=0:

Disc999-SatansChallengeOrNevilRidesOut-HAK3.ssd

(200 KiB) Downloaded 66 times

That gets you past the erroring room and into the further newly revealed rooms, but a couple of moves later you seem to invariably be asphyxiated by the mask, and I don't know how to remove it!

(The first newly revealed room displays the same room description as the previous room, but don't let that fool you. I think it really is a different room. You seem to be able to move beyond it and get to further new rooms -- if only the mask didn't kill you almost immediately!)

[fuzzel]

Here's the walkthrough to the error.

Not sure if this was the right thing to do but because a further newly revealed room started erroring once I'd fixed the room you led me to in the walkthrough, I've now hacked the program so that it traps all room numbers less than 18 where T%=0:


Disc999-SatansChallengeOrNevilRidesOut-HAK3.ssd


That gets you past the erroring room and into the further newly revealed rooms, but a couple of moves later you seem to invariably be asphyxiated by the mask, and I don't know how to remove it!

(The first newly revealed room displays the same room description as the previous room, but don't let that fool you. I think it really is a different room. You seem to be able to move beyond it and get to further new rooms -- if only the mask didn't kill you almost immediately!)

You're in esteemed company lurkio, looks like Alice had the same issue (The Micro User, January 1985, page 72):

Alice wrote:
I've got everything except the rope and the talisman so into the vault again for a thorough search and up comes the Angel of Death. Now I still don't know the last two lines of the Sussamma Ritual but neither does the program so scare him off with ****, drop **** - and **** kills me five rooms later ? Since REMOVE don't work I asked Microtest if this was a bug but no answer yet.

Presumably Alice is still waiting for an answer nearly 38 years later but I'll check subsequent Micro Users just in case. Incidentally the Sussamma ritual comes from Denis Wheatley's book The Devil Rides Through, hence the joke in the title - Nevil Rides Through (never read it or seen the movie). I'll have a browse through the listing again and see if I can work out how to fix the bug.

[fuzzel]

Alice owes me a pint! Looking at the listing (Sat2) lines 23 and 24 compare the verb entered with tables at &C33 and &880 respectively and then GOTO the relevant command line. Although the list at &C33 is intact the one at &880 is empty. That left me to try to work out what these commands were. By examining the lines pointed to I've had a stab at it although I'm not sure about some. Lurkio, could you change the following line on your hack version please:
7Q$=CHR$(141):CLS:V%=1090:$&880="xxx fig hit xxx rem sum xxx xxx xxx fly hel hin xxx"
Note that the fifth one along is remove to take off the mask.

[lurkio]

I’ll fix the disc-image later.

I did notice the missing data at &880 but hadn’t figured out what to do about it!

What a state this program is in!

[fuzzel]

What a state this program is in!

It is but we'll fix it, by heck we will! Anyway, good news, I've now found the rope (thanks to your bug fix) and the talisman! Stick that in your pipe and smoke it Alice. I suspect I still have lots to do to complete the game though but thankfully no sign of any more location bugs. I'm assuming that the Locdata file only contains compressed location text and not location directions or other messages? If the directions were corrupted then we'd be well and truly stuffed.

[lurkio]

Lurkio, could you change the following line on your hack version please:
7Q$=CHR$(141):CLS:V%=1090:$&880="xxx fig hit xxx rem sum xxx xxx xxx fly hel hin xxx"

I've changed it as follows:

Code: Select all

7Q$=CHR$(141):CLS:V%=1090:$&880="xxa fig hit xxb rem sum xxc xxd xxe fly hel hin xxf"

So hopefully (if I've understood the code correctly) you'll now be able to use the missing verbs even though we don't know what they actually are! E.g. perhaps you can just try doing XXB on every object in the game?! (And the same for the other XXx verbs?)

Disc999-SatansChallengeOrNevilRidesOut-HAK4.ssd

(200 KiB) Downloaded 66 times

[lurkio]

I also think I've spotted the bug at line 28 (there's an OSCLI in there):
28IFW%=0PROCqELSEIFj=4PRINTQ$+$&BC9:PRINTQ$+$&B9F:GOTO48925OSCLIRESTORE(4800+j):READP$:PROCp(P$)
If someone can fix this line I'd be very grateful!

I've changed it to this:

Code: Select all

28IFW%=0PROCqELSEIFj=4PRINTQ$+$&BC9:PRINTQ$+$&B9F:GOTO80EL.RESTORE(4800+j):READP$:PROCp(P$)

No idea if that's right but you now appear to be able to read the book and get an appropriate message.

Disc999-SatansChallengeOrNevilRidesOut-HAK5.ssd

(200 KiB) Downloaded 67 times

[fuzzel]

Here's a programming question regarding Satan's Challenge. The listing contains lots of procedure definitions suffixed with a number only, eg DEFPROC23, DEFPROC46, DEFPROC55 etc, and yet a lot of these aren't called within the game. Is there a way of invoking a procedure by calling PROCX for example where X is the variable 23,46,55 etc?

[fuzzel]

Lurkio, could you change the following line on your hack version please:
7Q$=CHR$(141):CLS:V%=1090:$&880="xxx fig hit xxx rem sum xxx xxx xxx fly hel hin xxx"

I've changed it as follows:

Code: Select all

7Q$=CHR$(141):CLS:V%=1090:$&880="xxa fig hit xxb rem sum xxc xxd xxe fly hel hin xxf"

So hopefully (if I've understood the code correctly) you'll now be able to use the missing verbs even though we don't know what they actually are! E.g. perhaps you can just try doing XXB on every object in the game?! (And the same for the other XXx verbs?)


Disc999-SatansChallengeOrNevilRidesOut-HAK4.ssd

I've changed one of the verbs in the list, I'd previously added fig (fight) as a synonym of kill but it actually needs to be swa (for swat). This allows you to solve the fly puzzle:
7Q$=CHR$(141):CLS:V%=1090:$&880="xxa swa hit xxb rem sum xxc xxd xxe fly hel hin xxf"

[fuzzel]

I've now fixed the spray can puzzle. Change line 7 to the below:

7Q$=CHR$(141):CLS:V%=1090:$&880="xxa swa spr xxb rem sum xxc xxd xxe fly hel hin xxf"

This game has so many bugs in it that I'm guessing it's a pre-release version and hadn't been properly tested. Maybe the cassette version was the original one and worked fine but the disc version was quickly knocked up without thorough testing. It'll be interesting to compare the two when the cassette version (eventually) turns up.

[lurkio]

This game has so many bugs in it that I'm guessing it's a pre-release version and hadn't been properly tested. Maybe the cassette version was the original one and worked fine but the disc version was quickly knocked up without thorough testing. It'll be interesting to compare the two when the cassette version (eventually) turns up.

I still think it’s likely that some files on the STH disc-image got corrupted at some point during the deprotection process, whenever that happened. Hence the missing room descriptions. There’s no way Alice wouldn’t have commented if room descriptions had been missing from their copy too!

But the fact that STH’s copy of the game has the same “REMOVE” bug as Alice’s copy does suggest that we’ve ended up with the same broken pre-release(?) version that Alice saw. Maybe the disc version was never debugged and never did get an official release..? (EDIT: The Micro User ad suggests it did.)

The text compression suggests that the tape version came first. Why bother with compression for a relatively small game if you’ve got the (historical) luxury of a hundred or two hundred kilobytes of space on disc (with the added benefit of fast random access)!

[lurkio]

Here's a programming question regarding Satan's Challenge. The listing contains lots of procedure definitions suffixed with a number only, eg DEFPROC23, DEFPROC46, DEFPROC55 etc, and yet a lot of these aren't called within the game. Is there a way of invoking a procedure by calling PROCX for example where X is the variable 23,46,55 etc?

Only by cheating! Something like this:

Code: Select all

NEW
AUTO

CLS

REM walk talk eat kill
V$ = "WAL TAL EAT KIL"

REPEAT

REPEAT INPUT"What now? "i$
V = (INSTR(V$,LEFT$(i$,3))+3)/4
V%=V:IF i$="" OR V%<1 OR V<>V% PRINT "Eh?":UNTIL FALSE
UNTIL TRUE

REM the magic:
?((?&B+&100*?&C)+31) = 48+V%:PROCn

UNTIL FALSE

DEFPROC1:PRINT"You walk on by.":ENDPROC

DEFPROC2:PRINT"You talk the talk.":ENDPROC

DEFPROC3:PRINT"You eat humble pie.":ENDPROC

DEFPROC4:PRINT"You kill time.":ENDPROC

https://bbc.godbolt.org/?embedBasic=CLS ... ENDPROC%0A



EDIT: better solution: viewtopic.php?p=398192#p398192

[julie_m]

I don't think it unreasonable to suppose someone foolish enough to imagine they have invented a copy-prevention system would also be foolish enough to expend more effort on trying to punish the pirate than on ensuring all goes well for the legitimate user. It's possible that in adding the piracy-detecting code to the finished game (which already includes self-modifying code, so you can see where this is heading .....), the author inadvertently corrupted it; or that some hardware configuration unfamiliar to the author caused false positives. But of course they were too busy showing off what happened to anyone thought to be playing an unauthorised copy, and too proud just to leave a simple missing object, unavailable direction or subtly altered puzzle dynamic that would still result in an unfinishable game without drawing attention to it, to care what happened to anyone playing a fully paid-up copy.

[fuzzel]

My sentiments exactly

[lurkio]

NevilDone.jpg
My sentiments exactly

Well done on finishing a very broken game!

Do you have suggestions for the missing room descriptions so we can insert them into LOCDATA and create a "fixed" version of the game while we wait for a copy of the tape (or in case it never arrives)?

[fuzzel]

Here are some more bug fixes, lurkio:

Unknown line at end of line 39 (looks like corruption):
FROM
39PROCch:IFr$="wine"ANDW%F%=73:PROC1:F%=0:PROCrem:FORl=1TORND(10)+5:PRINT"Zzzz":PRINT':PROCy(2):NEXT:PROCp($&B1F):D$=D$+"30":PROCu:GOTO16464
TO
39PROCch:IFr$="wine"ANDW%F%=73:PROC1:F%=0:PROCrem:FORl=1TORND(10)+5:PRINT"Zzzz":PRINT':PROCy(2):NEXT:PROCp($&B1F):D$=D$+"30":PROCu:GOTO80

Unknown noun at line 35 (this change ensures you die if you eat the food):
35PROCch:IFr$="fd"ANDW%F%=76:PROC1:F%=1:GOTO80
TO
35PROCch:IFr$="food"ANDW%F%=76:PROC1:F%=1:GOTO80

Error if program encounters this line due to lack of a couple of spaces (you can now READ the SYMBOLS on the dagger):
28IFW%=0PROCqELSEIFj=4PRINTQ$+$&BC9:PRINTQ$+$&B9F:GOTO80ELSERESTORE(4800+j):READP$:PROCp(P$)
TO
28IFW%=0PROCq ELSEIFj=4 PRINTQ$+$&BC9:PRINTQ$+$&B9F:GOTO80ELSERESTORE(4800+j):READP$:PROCp(P$)

The game should now be completable. I'll continue to hunt for more bugs as well as write up my walkthrough.
I'll also have a think about the missing locations' text.

[fuzzel]

Here's a walkthrough which should work after the above bug fixes

Code: Select all

W
W
N
E
GET TORCH
N
E
E
E
S
S
U
U
GET MASK
D
D
N
N
N
N
GET MATCHES
S
W
S
S
W
N
W
S 
W
W
GET BATTERY
FIT BATTERY
S
S
E
S
U
S
GET KEY
N
D
N
W
W
W
S
OPEN DOOR
DROP KEY
W
N
N
GET TAPESTRY
DROP TAPESTRY
E
GET SPRAY
W
S
S
E
S
W
S
E
SPRAY FLY
SPRAY FLY
DROP AEROSOL
W
N
E
N
N
E
E
N
N
E
N
N
W
N
W
S
W
N
W
S
GIVE MATCHES
GET PAPER
READ PAPER
DROP PAPER
S
TORCH ON
D
E
S
W
GET CROWBAR
E
E
N
WEAR MASK
N
REMOVE MASK
D
D
W
W
GET ROPE
E
E
U
U
TORCH OFF
S
S
W
N
W
U
E
N
E
N
E
S
E
S
S
DROP MASK
DROP MATCHES
TORCH ON
LOOK
E
N
N
N
E
GET SHOTGUN
W
S
S
S
W
S
E
S
S
OPEN DOOR
S
S
E
GET FOOD
E
E
N
N
W
N
E
PRISE BOARDS
DROP CROWBAR
D
GET SPADE
N
U
N
W
S
DIG
DROP SPADE
GET DAGGER
READ SYMBOL
DROP DAGGER
N
N
N
GIVE FOOD
W
D
S
SECURE ROPE
DROP ROPE
D
GET TALIS
U
N
U
E
S
S
W
N
W
S
W
S
E
GET GATE
S
S
S
S
D
E
E
N
N
D
W
W
N
E
E
N
N
SHOOT DOG
DROP SHOTGUN
W
U
S
W
W
GIVE GATE
D
W
S
GET CAND
RUB TALIS
E
N
N
BEFRIEND CAT
S
S
S
S
W
N
D
N
N
E
E
E
S
GET HORSE
N
W
W
S
W
W
S
U
S
E
N
N
N
DROP CANDLES
N
N
E
S
E
S
S
S
E
GET BOOK
READ BOOK
DROP BOOK
E
GET PAINT
L2R3L5R7
GET CUPS
W
W
S
D
E
GET WINE
DRINK WINE
GET BOTTLE
RUB TALIS
DROP HORSE
E
N
W
W
S
W
N
FILL BOTTLE
S
E
N
E
E
N
N
E
GET MATCHES
RUB TALIS
DROP BOTTLE
DROP MATCHES
E
N
GET CANDLES
RUB TALISMAN
GET HORSESHOES
PLACE HORSESHOES
GET BOTTLE
FILL CUPS
PLACE CUPS
GET MATCHES
LIGHT CANDLES
PLACE CANDLES
SUMMON
YOURE A DEVIL

[julie_m]

I have no trouble believing someone who could write an ending like that is the sort of person who could write a terrible copy-prevention attempt with so much emphasis on punishing the pirates and so little on the legitimate user.

I mean, I did write an ending that went "Congratulations! You baked a beautiful birthday cake! Game over", so glass houses and all that; but then, I wasn't deliberately setting out to create a hostile environment for hackers.

[lurkio]

Here's a walkthrough which should work after the above bug fixes

There were a couple of errors in the walkthrough (mainly inventory management) which I've fixed. I've also rolled all the outstanding updates into my latest hack of the .SSD:

EDIT: See new, updated .SSD: viewtopic.php?p=376673#p376673

Disc999-SatansChallengeOrNevilRidesOut-HAK6.ssd

EDIT: This is now unnecessary:

Code: Select all

W
W
N
E
GET TORCH
N
E
E
E
S
S
U
U
GET MASK
D
D
N
N
N
N
GET MATCHES
S
W
S
S
W
N
W
S 
W
W
GET BATTERY
FIT BATTERY
S
S
E
S
U
S
GET KEY
N
D
N
W
W
W
S
OPEN DOOR
DROP KEY
W
N
N
GET TAPESTRY
DROP TAPESTRY
E
GET SPRAY
W
S
S
E
S
W
S
E
SPRAY FLY
SPRAY FLY
DROP AEROSOL
W
N
E
N
N
E
E
N
N
E
N
N
W
N
W
S
W
N
W
S
GIVE MATCHES
GET PAPER
READ PAPER
DROP PAPER
S
TORCH ON
D
E
S
W
GET CROWBAR
E
E
N
WEAR MASK
N
REMOVE MASK
D
D
W
W
DROP MASK
GET ROPE
E
E
U
U
TORCH OFF
S
S
W
N
W
U
E
N
E
N
E
S
E
S
S
DROP MATCHES
TORCH ON
LOOK
E
N
N
N
E
GET SHOTGUN
W
S
S
S
W
S
E
S
S
OPEN DOOR
S
S
E
DROP SPRAY
GET FOOD
E
E
N
N
W
N
E
PRISE BOARDS
DROP CROWBAR
D
GET SPADE
N
U
N
W
S
DIG
DROP SPADE
GET DAGGER
READ SYMBOL
DROP DAGGER
N
N
N
GIVE FOOD
W
D
S
SECURE ROPE
DROP ROPE
D
GET TALIS
U
N
U
E
S
S
W
N
W
S
W
S
E
GET GATE
S
S
S
S
D
E
E
N
N
D
W
W
N
E
E
N
N
SHOOT DOG
DROP SHOTGUN
W
U
S
W
W
GIVE GATE
D
W
S
GET CAND
RUB TALIS
E
N
N
BEFRIEND CAT
S
S
S
S
W
N
D
N
N
E
E
E
S
GET HORSE
N
W
W
S
W
W
S
U
S
E
N
N
N
DROP CANDLES
N
N
E
S
E
S
S
S
E
GET BOOK
READ BOOK
DROP BOOK
E
GET PAINT
L2R3L5R7
GET CUPS
W
W
S
D
E
GET WINE
DRINK WINE
GET BOTTLE
RUB TALIS
DROP HORSE
E
N
W
W
S
W
N
FILL BOTTLE
S
E
N
E
E
N
N
E
GET MATCHES
RUB TALIS
DROP BOTTLE
DROP MATCHES
E
N
GET CANDLES
RUB TALISMAN
GET HORSESHOES
PLACE HORSESHOES
GET BOTTLE
FILL CUPS
PLACE CUPS
GET MATCHES
LIGHT CANDLES
PLACE CANDLES
SUMMON
YOURE A DEVIL

[fuzzel]

Thanks for doing the honours lurkio, I'm surprised you had to change the walkthrough though because it worked perfectly fine for me when I ran it. I'm happy to go with your version though. Regarding the addition of the missing locations I'll gladly do it but it'll take me a few days because I went to check through the listing again as a I recall there was mention of an old lift which may be relevant to one or more of the locations.

[fuzzel]

Here's a programming question regarding Satan's Challenge. The listing contains lots of procedure definitions suffixed with a number only, eg DEFPROC23, DEFPROC46, DEFPROC55 etc, and yet a lot of these aren't called within the game. Is there a way of invoking a procedure by calling PROCX for example where X is the variable 23,46,55 etc?

Only by cheating! Something like this:

Code: Select all

NEW
AUTO

CLS

REM walk talk eat kill
V$ = "WAL TAL EAT KIL"

REPEAT

REPEAT INPUT"What now? "i$
V = (INSTR(V$,LEFT$(i$,3))+3)/4
V%=V:IF i$="" OR V%<1 OR V<>V% PRINT "Eh?":UNTIL FALSE
UNTIL TRUE

REM the magic:
?((?&B+&100*?&C)+31) = 48+V%:PROCn

UNTIL FALSE

DEFPROC1:PRINT"You walk on by.":ENDPROC

DEFPROC2:PRINT"You talk the talk.":ENDPROC

DEFPROC3:PRINT"You eat humble pie.":ENDPROC

DEFPROC4:PRINT"You kill time.":ENDPROC

https://bbc.godbolt.org/?embedBasic=CLS ... ENDPROC%0A

Very clever and I'm determined (somehow) to understand it so it's on the to-do list for the week. I couldn't help noticing that the program seems to be self-modifying at line 150 (is that legal?)...

[lurkio]

I'm surprised you had to change the walkthrough though because it worked perfectly fine for me when I ran it.

Then is there a discrepancy between the version of the program Sat2 on my latest hacked .SSD and whatever version of Sat2 you’re using? Is the inventory size limit different for some reason?

[fuzzel]

I've been looking at the game code of The Twin Orbs of Aalinor to see if there really is a bug preventing you from going up through the trapdoor - you have a mended ladder but it doesn't seem to help. However, I got sidetracked by the way the game handles movement between locations. It's always fascinating, having written a couple of adventures in my time, so see how different authors go about things. In this case, CJ Potter has come up with a rather clever way to save a lot of space. What he's done is to set the locations out on a logical grid whereby when you go north, south, east and west the location number increases by 16, decreases by 16, increases by 1 and decreases by 1 respectively. The only further requirement is to determine whether a movement is allowed or not. What he's done is to, for the 118 locations, allocate 4 bits per location so only 59 bytes are required for the movements for all the locations. For example, &D00 contains the movements for locations 1 and 2. From right to left, bit 1 is W from location 2, bit 2 is E from location 2, bit 3 is S from location 2, bit 4 is N from location 2, bit 5 is W from location 1, bit 6 is E from location 1, bit 7 is S from location 1 and bit 8 is N from location 1. And so on to &D01 for locations 3 and 4... Clever stuff CJ.

[fuzzel]

Breakthrough on Twin Orbs of Aalinor! You don't need to go up through the trapdoor. Right, better get on and solve the game.

[fuzzel]

Twin Orbs now completed with maximum score. Will do the walkthrough for CASA shortly.

[fuzzel]

There's an error in Bill Trevelyan's The Body in the Bunker rendering the game impossible to complete. This is particularly annoying because it's right at the end of the game (I assume because now I have to go right back to the start again):

Code: Select all

2920FORI%=1TO70:IFo?I%>250;o?I%=128:T%=0

That semi-colon needs to be replaced with a colon. Lee/Lurkio, could you do the honours please updating the disc at bbcmicro.co.uk?

[lurkio]

in Bill Trevelyan's The Body in the Bunker ...

Code: Select all

2920FORI%=1TO70:IFo?I%>250;o?I%=128:T%=0

That semi-colon needs to be replaced with a colon. Lee/Lurkio, could you do the honours please updating the disc at bbcmicro.co.uk?

Done. Thanks.

Any idea about this?:

I'm surprised you had to change the walkthrough though because it worked perfectly fine for me when I ran it.

Then is there a discrepancy between the version of the program Sat2 on my latest hacked .SSD and whatever version of Sat2 you’re using? Is the inventory size limit different for some reason?