As always I am humbled by the depth and breadth of experience and knowledge on this list! Thank you all for sharing.
On Fri, Mar 13, 2026 at 12:21 PM Alan Cox <[email protected]> wrote: > > > On Fri, 13 Mar 2026 at 06:27, B 9 <[email protected]> wrote: > >> Thanks, Alan Cox, for the primer on game engines! As a fan of LISP, I'm >> quite intrigued that Infocom is derived from it. Is that the same as the >> "Z-machine" John mentioned? >> > > Yes. It goes through several iterations over time as the machines and > games got bigger. Some of the original source has been released so there's > a fun way to visualize it at work > > https://eblong.com/infocom/visi/zork2/ > > I'm also curious about Quill. Technically, the Tandy 200 has 40K of ROM, >> although I've only ever heard of people bankswitching the bottom 32K of it. >> Would Quill graphics translate to a black and white 240×128 pixel display? >> > > Probably very badly - but for most of the games the graphics were an > afterthought anyway. > > >> I remember playing Scott Adams' “Adventure” on a Vic 20. Even with >> everything on a cartridge, they still scrimped and saved bytes: All >> sentences were VERB NOUN and only the first few characters of a word >> mattered. Is the Tandy 200's screen (40 columns by 16 rows) big enough for >> Scott Adams split screen interface? If not, maybe one could use the builtin >> screen and an external (Disk & Video InterfaceI) screen simultaneously. >> > > The VIC20 is 22 x 23 display. The games ran on lots of 32x24 type displays > so it should be yes. A lot of period machines were 256x192 pixels or > thereabouts so 32 x 24 (eg the COCO, Spectrum, etc). > > Scott really had to squeeze to get the games into a 16K machine. > > https://solutionarchive.com/images/articles/pirate_byte/scan5.gif > > has a copy of the original BASIC engine as used by Pirate Adventure. > Listing 1 is a long listing that just generates the data file it uses, > listing 2 is the actual interpreter. > > The real system also included a game editor rather than the listing 1 > program to write the data files out. In order to get it faster and allow > for bigger games the game engine was turned into Z80 asm and changed a > little but the basic operation is the same. > > (long ago I worked at Adventure International UK) > > For The Quill a search for Gilsoft Quill will find you the original > manuals which gives a good flavour of how the table driven systems worked. > > Alan >
