eslapion wrote:Ghislain wrote:How difficult would it be to port the game to cartridge format?
Do you mean altering the software so it complies with the requirements of the hardware or taking the adapted software and putting it on the cart?
If the software is already adapted then it really takes a few minutes to make the cart.
I've been designing this game from the start to work with SD2IEC directory (or D81) in mind and adding disk D64 support at the end. So to convert it to Behr Bonz format it would not be a simple thing to do.
The Behr-Bonz presents itself in the form of 128 "windows" of 16KBytes each. At power up, window no. 0 is active and IO3 awaits a poke. Once a specific windows is selected by poking a number to IO3, the window is locked (IO3 becomes 'deaf' to any subsequent pokes) and the VIC-20 is reset to start the selected game. The window stays locked until a 'reset to menu' button is pressed is the VIC is powered off.
Windows are presented to the VIC-20 by having the lower half (first 8k) visible in BLK2 and mirrored in BLK5. The upper half of the window is visible in BLK3 and mirrored in BLK1.
If a Behr-Bonz was to be altered to carry a large game then I assume the cart would still present windows 0 at power-up but the 'locking' system would be removed so the software can freely choose whatever window it wants access to at any time. Also, the mirroring of visible halves of the window would become unnecessary. Each window would therefore become visible in BLK2 and BLK3, just like Scott Adams games are presently organised.
Added edit: The resetting of the VIC-20 at each change of the window would obviously also be removed.
The question is, do you also need extra RAM or does having instant access to any part of the game code relieves the need for the 32K of RAM ? I suppose it is still possible to have 8k of RAM in BLK1 or even in the 3K expansion area.
Is it even feasible to organise the game in a number of 16k sized windows ?
The game will have around 250 files -- a majority of which will be 1KB image files that you've seen me post here. And because the number of image files exceeds the 128 windows that BB has, this wouldn't work with that either. On top of that, Realms 5 has a 20KB "core" engine (loaded at memory location 12288) that handles commonly used routines like displaying text to the screen, math functions, inventory management, spellcasting, displaying graphics, loading files. Basically, this game is a 650KB block of virtual memory where items are loaded into the non-core portions of RAM on an on-needed basis. 650KB is what I chose because that encompasses about 4 floppy disk sides -- the same as Ultima IV.
To redesign the game into 128 16K sized windows would require a huge effort to reprogram the core engine (make it smaller to make it fit outside the 16K window) and what to do with the 1KB images? For example, when the game generates an encounter, 3 monster images are chosen at random. So the data that is to be used on an on-needed basis has to be dynamically accessed.
The game was designed with 32KB RAM expansion from the start. Much too late to restart at this point with the 20KB core engine practically almost finished now.
orion70 wrote:BTW, it would come handy if the digital copy will be organized in a single D81 or a SD(2IEC) directory, avoiding disk swapping, autoswap.lst, etcetera.
As for cart vs disk, I feel the former would be effectively used to play the game, whereas disks in a jewel case are more for collectible objects only (e.g., I play Theatre of War via SD2IEC and read a A4 print of the manual, but keep the disk in my showcase
). Also, I guess a cartridge would be far more expensive.
I figure that there will be about 250 files for the entire game which will fit onto a single D81 image which can contain up to 288 files.
As cool as it would be to have a cartridge version of the game, I've been playtesting this game a lot on a VIC-20 with uIEC and I've found that the game loads fairly quickly with SoftJiffy enabled. While the game supports a single 1541 disk drive, the recommended set-up in order of playability and performance will be:
1. uIEC or SD2IEC
2. 1581 disk drive
3. Two 1541 disk drives (there will be some disk swapping with this)
4. Single 1541 disk drive (more frequent disk swapping)
tokra wrote:Why not use the existing UltiMem-cartridge for such a project? It is an existing and working platform that provides everything a game like this would need. 8 MB of Flash-ROM and 1 MB of RAM. Hacking together yet-another-cart just seems overkill to me.
Anyways, first the game should be completed. Runnnig this from an SD2IEC or a 1581 will probably be just as good.
The game officially requires 32KB memory expansion. I thought about making the requirement 35KB (to use memory starting at 1024) but decided against it. Now I could make the game detect extra memory expansion at 1024 as well as Ultimem so that the game could "remember" what it loaded from disk so that it doesn't have to re-load an item it had already read from disk (or SD card) previously. But I'll get to that later (if I ever decide to provide support for even more additional RAM).
Pic of the day:
