MIST - A Multi-User Dungeon (well almost)

[fuzzel]

Well, I was supposed to be taking a break from game writing until July but I'm afraid I couldn't resist getting started on MIST, the sequel to LAND (although I've been sorely tempted to do the big daddy, MUD instead). My first decision was to use SDLIDE (BBC Basic editor for Windows) instead of Beebem for compiling the compressed locations text. Lurkio put me onto this a few months ago and it's a huge time saver. As an example, with LAND there are 4 files which are stored in four sideways ram locations each taking up approximately 16k and covering around 90 locations. To run the compression program in a Basic program on Beebem, I had to split each 16k file into 6 or 7 smaller files so each program compressed about 15 locations of text. This took between 5 and 10 minutes per file or a minimum of an hour to compress and create one 16k sideways ram file (it's awkward as well because each subsequent needs to know where the previous file's data ended so as not to overwrite anything or waste space). With SDLIDE and its seemingly unlimited memory I've been able to create a file which has the first 90 MIST locations which I've copied and pasted into from my bitd Mist text file. When run it takes about 5 seconds compared to over an hour on Beebem running at the maximum 50 FPS. Here's a couple of screenshots showing the opening screen and credits to the original programmers (who'd graduated from Essex before I arrived but who had handed over the administrative reins to a number people including Lorry, Orc, Bret and Zarf.

[fuzzel]

I'm making further progress. LAND was a 12 month project from the outset and that's exactly how long it took to write. With the essential adventure game engine having already been created I imagined MIST would take about eight months, a couple of months for the locations, a couple of months for the objects, three months for the puzzles and a further month for enhancements to the game code. I reckon the locations will probably now only take a month or so. A major tweak I've made to locations is to have two bytes per location, one byte being the sideways ram slot and the second the location number. This means you can wander seamlessly between the 360 or so locations whereas in Land there was only one byte per location and I had bridging locations and every time you moved it checked if you were using a bridge and it changed the sideways ram bank accordingly. It was pretty tricky to firstly find the minimum number of bridging locations required to save memory and secondly check that each sideways ram bank didn't run out of memory (and it was a very, very close shave with one of the ram banks). So now I'm on the third of four location ram banks and once finished I'll produce a big a3 map for each bank and start adding the objects and testing all the movements. A slight difference with MIST is that there are locations like the graveyard maze where there can be a number of random messages appearing so I've coded that into the game. For those who don't know, graveyards are a ubiquitous feature of the Essex MUDs, paying tribute to former players. When I first played and stumbled upon the graveyard I was a bit in awe of the wizards and witches who'd played the game and made names for themselves and when they graduated (or got booted out for doing little in the way of studying) they'd get a headstone in the graveyard. There are 26 randomly in MIST although I've noticed from the printout that a few were deleted for some reason. Here's an example of what I'm on about anyway:

[Canalboy]

Well, I was supposed to be taking a break from game writing until July but I'm afraid I couldn't resist getting started on MIST, the sequel to LAND (although I've been sorely tempted to do the big daddy, MUD instead). My first decision was to use SDLIDE (BBC Basic editor for Windows) instead of Beebem for compiling the compressed locations text. Lurkio put me onto this a few months ago and it's a huge time saver. As an example, with LAND there are 4 files which are stored in four sideways ram locations each taking up approximately 16k and covering around 90 locations. To run the compression program in a Basic program on Beebem, I had to split each 16k file into 6 or 7 smaller files so each program compressed about 15 locations of text. This took between 5 and 10 minutes per file or a minimum of an hour to compress and create one 16k sideways ram file (it's awkward as well because each subsequent needs to know where the previous file's data ended so as not to overwrite anything or waste space). With SDLIDE and its seemingly unlimited memory I've been able to create a file which has the first 90 MIST locations which I've copied and pasted into from my bitd Mist text file. When run it takes about 5 seconds compared to over an hour on Beebem running at the maximum 50 FPS. Here's a couple of screenshots showing the opening screen and credits to the original programmers (who'd graduated from Essex before I arrived but who had handed over the administrative reins to a number people including Lorry, Orc, Bret and Zarf.

MIST Start Screen.jpg

MIST COPY.jpg

Looking forward to it Fuzzel. Maybe I will have finished Land by the time you have finished writing Mist.

Canalboy

[fuzzel]

You'll get there I'm sure Canalboy even if you need a little helping hand along the way. Btw, did you manage to get back from the ivxvat vfyr with the loot?

[fuzzel]

I've now completed three of four location text files and am about to embark on the last. I keep thinking though about my MUD printout - I'm very, very tempted to temporarily pause MIST (possibly even posting it as it stands with all locations present in case anyone is in the mood for a walkabout) and create the location files for part 3 - MUD whilst I'm up to speed with the location creating module. From what I've seen of the text it's good quality, up to the standards of Level 9 in fact though I'll let others be the judge of that.

[Canalboy]

You'll get there I'm sure Canalboy even if you need a little helping hand along the way. Btw, did you manage to get back from the ivxvat vfyr with the loot?

I have been away since Thursday Fuzzel but I made it there then. Not explored yet but I hope to resume hostilities tomorrow.

Canalboy

[fuzzel]

Good luck!

[fuzzel]

Here's my weekly progress on MIST development. Having now successfully inputted all 365 locations (including 11 dead ones) I've produced the first of four a3 maps which I'll use for plotting the placement of the objects and puzzles. I've mentioned previously when developing LAND that I found it a pain having to use two bytes for the location numbers because they exceeded 256 and the same thing applies to MIST. Unfortunately for me I've realised that MIST has way over 256 objects (I make it 355 so far, the cat having 10 alone - nine lives plus one dead) so I'll need to perform two checks for objects everywhere which will eat into the available memory. However, on one of my problem-solving walks I suddenly thought, I've utilised sideways ram for objects, messages and location text, why not also use it for code? So I've just moved the input routine into sideways ram because it doesn't reference other sideways ram banks (now that would be a headache if it did) and this saves me over 1k which will compensate for the two-byte object problem. An example below shows it working and most of you will remember these characters from your childhood...

[fuzzel]

I've now added all portable objects to the game (158) and also the non-portable objects, eg doors (155). I still have the mobile creatures and simulated characters to include. In LAND there was one door (one door straddles two locations) which meant I needed six objects to cover it (2 x locked, closed and open doors) and this required a decent amount of memory to handle the unlocking, opening and closing of such, ensuring that both doors remained in an identical state at all times. I also had to prevent movements through a door if it was closed or locked. In MIST there are 11 doors meaning 66 objects are required. This would be incredibly memory hungry to program if I was to cater for each door individually so I'll have to devise a way of handling doors generically. I'm thinking about including an object type byte, for example type 1 = closed door, type 2 = open door, type 3 = locked door, type 4 = food, type 5 = marine transport etc which the program could check for rather than the object. This is how MUDDL, the Essex Uni MUD programming language worked. Now that the game has an authentic look to it with most objects added I'll complete the remaining two of the four maps and get to work on programming puzzles, first of which will be the door. Here are a few screenshots introducing some of the characters in the game:

Notso the cat - I'm not sure where he gets his name from:

The Irishman - I'll have to work out if he's pretending to be Irish or not.

Magar the dragon - you either have to give him treasure to score points or steal treasure from him - I can't remember so will investigate

Note that I've copied and pasted the text verbatim into the game so you pedants out there can leave me alone for the moment!
I'll correct (some but not all if past history is anything to go by) grammar and typos at a later date.

[fuzzel]

Canalboy made a very good point yesterday with regard to LAND. He's nearing the end of the game but has missed a few treasures, the reason in one or two cases being that the location text doesn't always list the available exits. Although due to memory constraints I haven't been able to include an EXITS command in LAND, I've added it to MIST for the moment and hopefully it can stay in. I'll have to set a nolook flag in each location though where I specifically don't want an exit to be shown, for example in maze locations or where there's a secret / hidden room. See example screenshot below.

On the subject of mazes and MUDS I recently read about a novel maze where all room descriptions were identical and you couldn't drop objects to help map it (I think they sank into a swamp). The clever solution, it being a MUD, was that you needed a number of players to collaborate, one standing in each location and an extra player who could then map the maze. Clever eh? I'll pore through my MUD printout at some point to see if I can find it.

[Canalboy]

I seem to remember one of the Phoenix games (either Fyleet or Sangraal I think) having a very clever maze that rotated one move NE every given number of turns so that the player has to compensate every few moves (E nominally becomes SE for instance). Jonathan Partington in particular seemed fascinated by mazes and produced some very devious ones.

[fuzzel]

Whilst I'm writing MIST I'm trying to be innovative so by the time I get round to writing MUD, the grandaddy adventure, the framework of my adventure writing system will be nigh on where I want it. I've been perusing the MUD printout and noticed that there are quite a lot of locations where you're blocked from moving in a certain direction if there's a certain type of creature there (eg an undead one or an animal). To program this into each direction movement subroutine would be pretty inefficient, especially when there could be a dozen undead creatures wandering around. So I've created an object class so all the undead, zombies, gargoyles etc have the same type. I've also added a lookup table for movements consisting of four bytes per blocking test (location1, location2, object class, direction no.) and this is called before you move to see if your way is blocked. I've also added another blocking table, this time where you need to be carrying something through an exit or your way is blocked. Finally I've added a WHERE command as it's quite helpful when playing the game. After all, we've all had to drop something at one time or another and subsequently can't remember where we put it when we find a use for it.

For another challenge, I might program a FIND command, whereby you move one location at a time towards the object, eventually reaching it. It took a bit of thinking about to work out how to do it but I think I've got it. As I recall at least one of the Level 9 games had this command.
EDIT: Not sure whether the gargoyle is supposed to be sulking or skulking, must find it in the printout...

[Canalboy]

The gargoyle sounds terrifying. I can't stand Status Quo. Is MIST as large as LAND?

Canalboy

[fuzzel]

Canalboy wrote:
Is MIST as large as LAND?

MIST has 369 locations currently with a few extra locations to be added, Land has 346 so they're fairly similar in that regard.
Where MIST is much larger is in the number of objects, LAND had 205 whereas MIST will have 400 by the time I've added in the simulated players.
I've been working on adding the FIND command over the last few days, in its current guise if you type FIND OBJECT it will calculate the route to it and start you off on the journey, moving you to the first location on the route and then telling you how many moves left until you find it. However, you could find yourself being prevented from getting there if, for example, there's a locked door or monster in the way. It's a pretty useful command but a satnav it ain't*, I'm sure if someone compared the program's route to the shortest route worked out by hand in some cases it would lose but then, it's still a useful tool. I've worked out how to improve it (I'll keep that a secret in case anyone wants to work out how I've programmed FIND) but due to memory limitations I won't bother implementing it yet. Also, to avoid having to keep typing FIND OBJECT I'll incorporate an AGAIN / A command in a future version. See my example of FIND in action below:

And lurkio, please don't mention "It is now 1 locations away." !
And finally, the status quo fan gargoygle is sulking (I've just checked my printout).
* "It is now 0 locations away." - maybe I'll change that to "You have arrived at your destination."

[Canalboy]

I have no doubt you will get it up and running fuzzel. Will lurkio be doing his testing on it later on?

Canalboy

[fuzzel]

Thanks for the encouragement Canalboy! Things have been going well with the development recently, though I had a hiccup earlier in the week when I found the parser didn't recognise the grating after I'd opened it. After an entire afternoon failing to fix it I decided to create a standalone input module for testing, which was worth doing anyway so I could refresh myself on how it worked, and I fairly quickly found the bug which was a consequence of me splitting the portable objects from the non-portable ones due to the sheer size of MIST (it has over 256 objects). My main task at the moment is going through each of the four location files, checking all the directions match my printout, fixing typos and grammatical errors, adding the 8 location flags (utilising the 8 bits for a byte, for example one specifies whether the room is indoors or outdoors for weather messages and another specifies whether the room is light or dark) and finally adding those puzzles relating to movement around the game, for example the grating mentioned above:

And the portcullis which I've just included:

You'll also notice Lorry the arch-wizard standing there. He was a major contributor to MIST-2, which is the version I'm porting, along with Richard Thombs and Bret(t) Giddings who wrote LAND with Jon Cornell and myself. He left Essex before I arrived and I think I met him once when he popped over for a day. I'll have to get in touch with him at some point and find out what the MIST-2 additions were.

[Canalboy]

In these troubled times I like forward more than ever to a MIST release. All the best to you and lurkio for his work on the game too. I may be a pain and offer some help later while playing as per LAND if that is ok with you.

Canalboy

[fuzzel]

Hi Canalboy, I'm working as fast as I can. Please feel free to provide any help to other players of MIST and LAND as you see fit, though I might get there first. That's the spirit of Stardot!
Incidentally, I've had 24 hours off from programming, I managed to get the mobiles working on Monday (and there are 72 compared to LAND's 26) by which I mean movement and combat. It wasn't as straightforward as turning them on again because of the way the locations are arranged in MIST compared to LAND. When I wrote LAND I used 8-bit location numbers (1-255) but because there were over 300 locations I divided the map into four and had bridging locations between each area (or quadrant). This took a bit of programming to allow you to move between them. To also accommodate mobiles moving between quadrants would have involved a lot of additional programming so I simply restricted them to their own zones. In MIST, because it has 16-bit location numbers, the mobiles are quite free to wander round (although I can designate individual areas for each mobile if required). There is a perceptible pause though when entering a command as the program handles mobiles movements. Maybe I've included too many (all the "players" from LAND have been included, for example, Toodleoo, Tania, Ticklemyn and Roy - they're very keen that lot) and I'll include a WHO command so you can see who's playing at any one time, just like the real thing.
Anyway, my digression in the last day was down to me thinking about Level 9 and how they managed to squeeze so much text into their games. I read somewhere that they used Huffman compression to squeeze 100% of text down to less than 50% in memory so I thought I'd do a bit of research to see how Huffman works. I've written a BASIC program to encode a piece of text - "she ties the tethers" a la Huffman into 36% of its original size (I used @ as carriage return). The guide I used is here:
https://filestore.aqa.org.uk/resources/ ... -TG-HC.PDF
Now, if only I could use the "code" box option on Stardot, I'd be able to copy and paste my code here to show how I've managed to do it, although my method as an amateur programmer is probably rather convoluted and inefficient. I'm tempted to switch from my current compression method to Huffman if I can expand the tree to accommodate all the individual characters in the text. Rather than use upper case I'd probably have a control code character to convert lower case to upper case wherever found.
EDIT: I'm proper chuffed because I've managed to use ROL A for the first time in a program! Now, I must find a use for some of the other more esoteric 6502 commands such as BIT...

[fuzzel]

The MIST printout I'm working off is comprised of the following sections:
1. Location text and directions to other locations, also including conditions such as door:N so if there's a door
there it has to have an "open" setting to allow you to go that way
2. Objects text and attributes - eg its initial location(s), its value, its initial setting (eg locked for door)
3. Messages - all the game's messages except those hardcoded into the game eg "What now?" - I don't have access to those messages.
4. MUDDL game code - when you type a command it checks through this list and performs the appropriate action
eg EXAMINE DWARF - Message 1001 - "He's a bit hairy (or is that a she?)"
This is the bit I'm working through at the moment having entered all the location text and objects. I'm putting all the game conditions into a spreadsheet (there are over 300), and giving a designation to each one on the following basis:
Y - This command MUST be included in the game - it's an essential element of a puzzle or gameplay or it's a witty message.
N - Unnecessary - these are trivial commands which don't contribute to you winning the game but which someone thought it would be fun to include at the time, eg EATing different objects - perhaps a player asked them to.
B - Berserker commands - in the original MIST at the start of the game you could decide whether you played as a berserker or a mage. Berserkers only gained points by killing other players or game-resident mobiles whilst mages gained points by collecting and dumping treasure as well as killing others. There were certain nasty objects in the game which only berserkers could use. Berserkers also had their own levels. As this is a single-player game there's no need to include the berserker stuff.
W - Wizard commands - in MIST wizards could utilise some extra commands to enhance their enjoyment of the game, eg SNOOPing on other players or SGETting objects in other locations or GOing to any location. These were purely for a bit of fun when interacting with other real players. Again, as a single-player game there's not much use for these commands.
C - Combat commands - MIST was a pretty bloodthirsty game and there are lots of mobiles to kill (with a variety of weapons) so the game accommodates you attacking various different creatures with a decent variety of weaponry. Each weapon has a different "attack" quantity, for example the chainsaw attacks with 35 whereas the sabre only attacks with 15. I'll include as much of this as I can, space permitting. Note that there are non-violent ways of dispatching a lot of the mobiles for those of you who don't like the combat element. I might even add more of my own.
J - Juvenile commands - this is the sort of stuff amusing to teenagers, probably less so to those of a certain vintage. They accommodate a good number of different swear words etc. I'll probably leave them all out.

Further to my previous post I'm going to remove the FIND command. Testing it further it only really works with objects that are nearby; for further away objects where you'd probably have to negotiate a maze or get past some creature or through a locked door, for example, it didn't really work. It also took up quite a bit of valuable memory. I'll leave the WHERE command in and rather than just make this available to wizards like the original game, I'll make it available to anyone who's made it halfway through the game (level 6 of 10). I've also added a "WHO" command so you can see who else is currently playing. Like in the real world they'll drop in and out of the game. Note that these "players" aren't just there to add a bit of faux-authenticity, you'll need to interact with them to solve a few puzzles.

[Canalboy]

It sounds like it's bubbling away nicely Fuzzel. You certainly have your work cut out as you are having to decide what stays and what goes as well as the technologically difficult part of the porting process.

Keeping the game sensitive to the original while having to create a contemporary framework is a real challenge.

Canalboy

[fuzzel]

Thanks Canalboy, things are going very well and I think I should have enough space to get the essential things included in the game. I have a trick up my sleave to squeeze a bit more in which is to potentially move some of the subroutines which don't access sideways ram banks such as input into sideways ram. The beeb seems to be able to handle this ok. When I first started coding the puzzles I adopted a bit of a scattergun approach - when I spotted an interesting object or location in the listing I included any relevant puzzles. Now that I'm working my way through the listing and programming the puzzles sequentially I'm finding that I've already done a lot of them. So hopefully I won't be too far off a test version. I think I'll do the initial testing myself then pass it on for further testing before releasing the final version.

[fuzzel]

I've now added all of the major puzzles, all that's now left before testing is to include some of the "nice to haves" which are mainly trying to anticipate some of the things that adventurers like to try. Some feedback from Canalboy when playing LAND was that he found it very frustrating running out of health points because the food items that boost your health are one use only. With this in mind I've decided to change the way MIST handles health, for one thing your maximum health is now a function of the level you've reached (MAX-HEALTH = 50 + LEVEL*10) and even better, when you eat an object it then randomly appears somewhere else in the game (though not necessarily somewhere you've already visited, that's in the lap of the MIST gods (arch-wizards)). Here's an example screenshot:

I've also added a LEVELS command so you can see how many points you need to reach to get to each level (oops, spelt Necromancer wrong):

Once you reach the rank of enchanter the WHERE command becomes available to help you locate stuff you've lost:

[Canalboy]

Hello fuzzel

How is Mist coming along? Looking forward to it.

You might also be interested to know that a sequel to the old 1981 Commodore-Pet game Weird Wood has been released twenty nine years later! You can read about it and download a Windows compatible version of the new extremely large game here.

http://8bitag.com/info/weird-wood-ii.html

Regards

Canalboy

[fuzzel]

Hi Canalboy, that Weird Wood game definitely looks worth a play, if only I could find the time!
Mist is coming along very nicely btw, I have a couple of fairly trivial and one major puzzle to add, shouldn't be that much work really, then I'm going to redraw my four maps to include all the objects and puzzles. I'll then conduct a walkthrough for each map and thoroughly test each command. It's a bit time-consuming because of the 16-bit locations and objects, I'll need to ensure that you can't use one object with the same low-byte number as another in a puzzle (the same applies to the locations). I then need to add a save / load game routine. Finally I'm looking at improving the way the sideways ram banks are handled - ideally I want the program to use whichever sideways ram banks are available rather than the way Land worked which was to use specific sideways ram banks (eg SWR0 for messages) which caused problems for real beeb-users who had their sideways rom/ram boards configured differently. Watch this space!

[Canalboy]

How goes Mist Fuzzel? A New Year treat I hope?

[fuzzel]

Hi Canalboy, and Merry Christmas to you (and all) !
MIST goes well, in fact very well, I've just completed my first walkthrough with bug fixes. It would certainly be available for testing with a few minor tweaks if only I could find someone to help...