Workprint – May 2019

Last time I talked about the new, C64-specific version of C64CD blaster Stercore and this month continues that “trend”. It’s now officially called Stercore XD and I’ve actually got the majority of it written and working somehow!

Memory is getting very tight but all of the graphics are done now including some sprite animations – one of the aliens and the explosion have been “inherited” from Super Hyperzap – and everything just about fits into the lower half of the C64’s RAM after decrunching until the code grabs around 10K more whilst unrolling the background scroller. Spacial awareness is important here because I’m planning to put the final release version of Stercore XD out as a cartridge image for the RGCD competition. To that end the build process automagically makes a working CRT image for testing.

I still have a “to do” list including tweaks to the collision detection, a rewrite of the enemy movement code to optimise it, adding explosions and bolting in the simple attack wave driver from Super Hyperzap with a couple of small tweaks but, since there’s currently only about 280 bytes of ROM left in the 16K block the game has to occupy as a cartridge, some concessions might be necessary. To give a sense of scale, this paragraph is 457 bytes…

Workprint – April 2019

The work on pushing new graphics into the updated C64 version of Stercore is progressing slowly but surely; so far I’ve replaced pretty much all the original attribute-flavoured tiles with graphical versions – as in the screenshot from Char Pad below – but they’re still in need of tweaking to remove or rework some elements. It does look like there’s a reasonable amount of space left in the character set for some extra detail though and, although there’s a few ideas brewing for new graphics to add, I’ll need to sit down and check through the maps first to make sure everything is present and correct before assigning characters.

Apart from that there’s not much else going on at Chez Roundabout because I haven’t really had much time – a dodgy shoulder has been making typing very difficult for most of the last month, which is frustrating when you’ve got ideas but can’t do much with them – which goes at least some distance towards explaining the lack of blog posts – but there’s a few odds and ends on my “to do” list for when things hopefully settle down in a week or so. And at the same time there’s all of the regular urges to write yet another horizontally scrolling shoot ’em up that need be fought…!

Workprint – March 2019

One of my “defining traits” is a quite frankly ridiculous lack of organisational skills, in fact it comes as something of a surprise to people who’ve known me for any length of time that I get blog posts up on what are, by my standards, a fairly regular basis. As a result of that there are a lot of projects hanging around my hard disks which have been put aside for one reason or another, sometimes either on the cusp of being completed or actually done and dusted (although in one case it’s a port and in need of an overhaul since the original version has subsequently been improved).

So with spring approaching I plan to apply the defibrillator a few and right now I have two in mind, both of which C64CD projects; I’m keeping one close to my chest until it starts to properly exist past a few sprite routines that need recoding anyway, but the other is a reworking of Stercore 64 which re-imagines it as a bespoke C64 game rather than a Spectrum port. That’s more difficult than it might sound because the game scrolls at a character per frame and the landscape has two layers with one passing over the sprites, so my “plan” is to rely on the way that one of the character multicolours always remains behind the sprites regardless of the priority register.

That’ll give me a black background with one other colour for the background layer and, if I can scroll the colour RAM, five or six foreground colours; the sprites can then pass between the two without needing any complicated sprite clipping code since the hardware will do the work for me. That said, actually drawing something half decent with those restrictions is difficult and, whilst games like Implosion and Shadow Skimmer carry it off well, I’m no John Cassells or Mat Sneap…