beginner project - a text-based game for vic-20 ?

[Mike]

What level of extra ram would I likely need, 3k 8k 16k etc.? [...] I like the idea of trying to fit it in 8k. 8k ram seems a common cart and from what I understand, higher ram configurations would probably be able to load it as well?

You can savely assume that a game which requires 8K will also run with a 16K or 24K expanded VIC-20. This is because the three main different things to the unexpanded VIC, namely the screen address (shifts from 7680 to 4096), the colour RAM (shifts from 38400 to 37888) and BASIC start (shifts from 4096 to 4608) all remain the same across the 3 different extensions. Only the top of BASIC RAM differs, but other than giving more RAM for the programs (obviously) all other POKEs and PEEKs remain the same. Incidentally, that also means a game designed for +16K will run on a +24K expanded VIC-20. Regarding user defined characters with +8K or more, that topic has been discussed in recent threads.

Two points to note:

- the biggest single memory expansion available from Commodore was the VIC-1111, +16K RAM. This is a 'soft' limit I'm setting myself, i.e. I do make myself at least *some* thoughts whether or not to straddle that boundary, because ...

- when confining oneself to 'original' CBM hardware at that time, one would have had to buy a cartridge extender, buy a +16K and +8K RAM extender, open the latter one to set it to BLK3, and insert both cartridges into the extender just to get +24K RAM. Obviously quite an expensive method.

...

Of course there are also third-party RAM cartridges around, even with more than +16K RAM. From the programmer's point of view, they are all equivalent.

Finally, three newer cartridges, namely Mega-Cart, FE3 and Ultimate Expander have found some good acceptance. These all allow to extend BASIC memory by +24K, and also allow for RAM in BLK5, which just unfortunately is not continuous with the other RAM extensions, thus can't be added to available BASIC RAM. Even if you write your game for +24K you can be sure that 200+ people around the world can run it on real hardware. All those who do not own such a RAM expansion still could run it in VICE - maybe even giving them some incentive to buy one of the aforementioned carts?

Greetings,

Michael

[OBSysteme]

Hi guys, I am picking up from where I left off again, the project is still alive!!!

all mapping is done and I am working on a data-frame-table and navigation engine along the lines of the model presented here:

http://www.atariarchives.org/adventure/chapter4.php

Still writing and thinking alot about content for rooms in the game and possible escape paths. I have also created a couple of NPC characters which will be in the game.

I have also decided that the game will include a minimal fighting routine, for those that want to try and escape using the violent option (hahaha but will it get you anywhere?).

coming back to the data table, is there a maximum number of columns that the vic20 can handle?

ex.:
data 1,4,5,7
data 1,4,6,7,8,3,2,7,4,4

How many numbers can vic20 handle in a data-line?
I want to maybe fit things other than just n,s,e,w,up,down in there if possible.

thanks for anyone who can help.

OBS

[Mike]

How many numbers can vic20 handle in a data-line?

Just as many as fit on a logical line, which would be 88 characters (4 screen lines).

If you embed strings into DATA lines, it is advisable to frame them with double quotes when they contain spaces, commas, or colons. Otherwise, spaces at the beginning or end of the string are stripped, commas are mistaken to end the current DATA item, and colons signal to end the DATA statement alltogether. Probably not what you wanted.

[OBSysteme]

Hey Mike, thanks, that is good news, more than iwhat I imagined.

by double quotes, you mean "string" or ""string"" ?

[Mike]

by double quotes, you mean "string" or ""string"" ?

If I had just refered to quotes, I could have meant one of these: -> ' <- single quotation marks (Shift + 7 ... the CBM glyph looks more like an accent, though), or -> " <- double quotation marks (Shift + 2), the latter which are actually used in CBM BASIC to delimit a string at both ends, but are not part of it. A$="", for example, assigns an empty string to A$, with length 0.

Strings can also contain double-quotes, but they need to be placed into the string with concatenation: A$="A QUOTE IN A STRING: "+CHR$(34)+" <- HERE IT IS."

PRINT A$ then results in:

A QUOTE IN A STRING: " <- HERE IT IS.

However you cannot place this into DATA statement, i.e. something like

DATA "A "+"STRING"

will not work (you'll get a ?SYNTAX error, when you try to read that item).

[OBSysteme]

It's been a while since I gave news on my beginner project, so here it is. I am happy to say the project has been advancing steadily, a bit each day. I am still sketching out some things, but now the actual "programming" on the VIC has also started, with a few lines typed-in each day.

I have received my memory expander + EProm with Programmer's Aid in it (Eslapion's fantastic handywork) so in terms of meterial I have all I need now.

I am working on a new plot-line since the subject matter in my game is a bit touchy. I now try to develop a plot-line that moves away from the player thinking he does not belong in a psychiatric ward (that is not very respectfull). In the new plot, it is no longer a question of whether you think you belong there or not or if you are sane or not. The plot evolves more along the lines of issues happening at the institute, which convinces you of the need to escape because you fear for your life!

Some other things to look forward with this came, as I am struggling to make a game with high replay value:

a) 3 levels of difficulty (e.g., number of personel in the building and their attributes & behavrior, levels of physical and psychological "hitpoints", etc...)
b) puzzles (people and objects) are not always the same, or at the same place, different each time you play
c) 3 ways of escaping and winning the game, including one non-violent way from start to finish!

So if a person wants to challenge himself, if can try to escape at difficulty levels 1, 2, and 3, and try to find all 3 ways of escaping.

Even after that, one can still play over and over again, because the puzzles will change even if the building does not change. For example, even if you know what to do to escape, you sill have to go find and get the clues in the game because they will change each time you play the game. Having a walkthrough in your head for the game will not eliminate the thrill of trying to accomplish it without getting caught.

The fun can continue because it becomes a matter of how many time you actually manage to pull-it off and escape from Estrapad.

Other things: I plan no big complicated puzzles. I don't want to have players be stuck for a long time on a single puzzle, which then gets forgotten once it is solved. I don't want you to hate an abstract puzzle... I want you to hate the person who has put you in this hospital (more role-play and fiction, less abstract puzzles).

I am a long way from it, but down the road I think such a game will need volunteers for test play, in order to balance things.

[griz]

Your first PC was a 486? That's too bad you missed out all those years ago! Never too late to appreciate the Vic though. It's a terrific system for learning on and I see that you have a beautiful set up.

As mentioned already, Tim Hartnell's book (Creating Adventure Games on Your Computer) is excellent but you may run out of ram quickly on an unexpanded Vic. Classic book.

You also might find these of interest :

TECHNIQUES FOR WRITING YOUR OWN ADVENTURE GAME : http://www.atarimagazines.com/compute/i ... E_GAME.php

WRITE YOUR OWN ADVENTURE PROGRAMS FOR YOUR MICROCOMPUTER : http://www.worldofspectrum.org/infoseek ... id=2000424

Enjoy!

[OBSysteme]

hi Griz!!! thanks for these links/books! It is much appreciated.

Indeed, I have resigned myself that this project will require ram expanssion.

I must say that while the first PC I owned was a 486, I used to get to use Apple II's (school) and Tandy computers (friend) quite regurlarly before that. Oddly, it seems no-one had Commodre beasts in my circle of friends and relatives back then.

[Shamusboy]

Griz, that first link is great. I happen to have that issue as well and I'm starting to go through my other issues to see what IF gems there are. I wondered how one-byte pointers worked and this article lays it out very clearly.

I'm also working on an IF game and am just starting to figure out what I want to accomplish with it. Like OBSysteme's, it will be written in BASIC at least to start with and if I can keep it to a low memory footprint, all the better. Still, I do have a RAM expander, so I can evolve as the game does.

When done, I'm seriously thinking of doing a "Limited Edition" physical copy along the lines of the Infocom packages. That or an illustrated folio of the game. Not sure. Perhaps both or neither - have to finish the game first

How is your game coming along OBSysteme?

Oh and a late "Happy New Year" to you as well

[OBSysteme]

Hi Shamusboy!

Thanks, happy new year to you as well!

My text adventure project, periodically stalls and picks-up again, as time permits, and as it compete's with other passtimes. Some progress is made, as I now have Ram expanssion + programmer's aid EPROM and actual programming and saving to disk has begun. The project mostly exists in an Excel file, storing maps, Data lines, program lines, and lists-indexes of variables and potential Non-player characters and events in the game...

The list of ideas and plots for the game is not finished but well advanced, and part of the game's "static" content has been partially coded into DATA statements. I am looking into having a dual section of data (2 datasets) one for all numerical variables, and one just to store room-related descriptions.

The game is still awesome, troubling and exciting in my head! hahaha.... I just need to do less daydreaming about it and do more coding of what I have already decided upon.

By the way, since we are both onto IF projects, don't hesitate to take hold of this thread and post any questions on IF and basic programming, as I am sure I will benefit from it as well.

I did some cleaning and major shuffling in my basement and the Vic-20 now has prominent and "dignified" place on my workbench. I should be diverting more time to it now.

I am getting attached to the idea of releasing "do it yourself" physical copies as well. Probably tape since they are so cheap hardy as a medium (better than floppy) and backup copy can be made on side B.

cheers!