Femtotro (C64) and Zeptotro (C64)

Last week I was looking back at my intro collection Backlog and there was some method to my madness – most of the time there isn’t and it’s literally just madness – because at the time of writing I already had Femtotro pretty much completed. This new CSDb Intro Creation Competition entry is based on the small Babygang intro included within Backlog and, as with that 1991 release, my intention here was to keep things small. To that end the custom character set, some of the sprite definitions and chunks of data used by the code are being decompressed into the screen RAM and then hidden by changing the attributes for those areas so they match the background colour.

The result is, after some rather unceremonious hacking at 4-Mat’s music with the excellent Regenerator to relocate its work space down memory, an intro that can run in under 4K including the screen RAM as long as whoever is writing the scrolling message doesn’t feel particularly verbose. Even with the longer text included in this release it finishes near $1600 so is hovering around the 4.5K mark and, again, that’s with the screen RAM. There’s also no raster interrupt code included, another decision initially made to keep things close to the bone that also means there’s nothing to reset on that front once the space bar is pressed.

Then there is Zeptotro, a less than sensible attempt to take the idea of loading data into the screen memory that Femtotro is using just a teensy bit further. It only decrunches into the screen memory and never uses any space above $07ff when executing – the final memory footprint is $03c0 to $07ff – which sort of makes it invisible because, if there were a program linked to it, the intro could literally just exit by jumping straight to the start of its decruncher without having to relocate any memory first. Once again, the music is by 4-Mat and has been rather rudely pulled apart to relocate it in memory, in this case so that it could be included directly into the intro’s source code for brevity.

That does mean I owe Matt an apology for being so brutal to his music driver on both occasions, but it was in a really good cause I swear! As is always the case, there’s source code available for both Femtotro and Zeptotro over at GitHub if anyone fancies a little delve down through them.

Workprint – December 2018

Time for another workprint and I’m afraid this one is pretty much going to be a case of me saying “watch this space” in various different ways because, whilst there are things ongoing for amongst other things the CSDb Intro Creation Competition, I’m keeping the entire deck of cards close to my chest for the moment to allow for random rewrites or complete changes of project priority. There are at least two more intros being prodded at right now and one uses an FLD routine, but that’s about as specific as I’m willing to get for the moment.

But one of the sillier ideas I came up with a few weeks back but ultimately decided not to pursue – one of the down sides to the CSDb ICC is that you can only enter three intros, I usually have twice as many ideas – was by total coincidence realised by ROLE a few days back, although my version was going to be a bit more involved technically, pushing into the side borders and stretching the sprite. Perhaps I’ll do my interpretation and release it alongside the competition if I can find some free time?

There’s going to be a couple of releases on t’other label now that December is under way; it’s game code that’s been loitering around my hard disks for an age that was essentially put aside but not quite forgotten entirely when I switched to “demo mode”. You could consider those to be a “festive season bonus” but, since I dislike said annual event with a passion and am nowhere near organised enough to arrange something like that anyway, it’s really just me “clearing the decks.

Watching Backlog (C64)

Since I’m in an intro-y kind of mood right now I decided to have a ponder about “past glories” and loaded Backlog, a collection of intros I wrote for various people during the 1990s that were thrown together into a single file at the end of 1999. Perhaps unsurprisingly the show starts with an intro, although this one was written specifically for the job; it has a logo by WHW Design, music from 4-Mat – one of his earliest tunes as a member of the group if memory serves – and the design was based on a Cosine intro Hookie used during the 1980s.

The first actual intro in the collection was written in 1991 for Chancer when he was a member of Babygang and is one of two I coded for them. It saw a fair amount of use in part because it was designed to be compact, with everything bar the music being crammed into the first 4K of memory and there are even a few cases of this in the wild where the music was removed entirely in order to save even more space. I’m told that it also compresses rather well, although that’s more by luck than design on my part!

The Derbyshire Ram intro that comes next in the collection hails from 1992 and is pretty simple stuff with a swinging logo, scroller and some cosine-following sprites but, because I’m thoroughly disorganised and it took a little too long to code, so Barry had already left Deadline by the time everything was finished! And there’s a similar story behind the Success intro that follows as well, it was commissioned by Mistri in 1993 and I spent some time cramming the logo and larger character set into a ridiculously small amount of space only to find out that they’d just joined forces with The Ruling Company and my code would therefore remain unused.

Next is the only other Cosine intro included in this collection, which was first used for the Electronic Music System V7.03 in 1997 and subsequently linked to a couple of Cosine games around the same time. The main “design choice” was to work within a reduced area of the screen by drawing a box around everything apart from the logo and this is the primary inspiration for Refix 2017. The final intro in the collection was coded in around five hours to go in front of A Lil Bit Of, a three part demo by Carcass again put out in 1997. The music in the final release was composed by Necrophobic, but I didn’t realise there was a new tune being supplied so the intro is timed around the Replay tune included on this release. Once space has been pressed we get to the finale, another 4-Mat tune accompanying a large “end” logo that swings onto the screen.

There are a couple more intros that could have been included including the second Babygang intro mentioned earlier – there’s an extremely good chance that I actually forgot about it when compiling the collection – and one I did but, if memory serves, never quite finished for Rebel Alliance around the time I was coding Pink Elephants In Lemonade. And because of those two the idea for Backlog 2 has been stewing pretty much since the first one was released although, unless I’m forgetting something else, there’s not much to go into it after those and the more recent Cosine intro used for GR9 Strike Force