World of Illusion is supposed to be really good. That and James Pond.
Blog: http://www.breakintoprogram.co.uk YouTube: https://www.youtube.com/BreakIntoProgram Ko-fi: https://ko-fi.com/breakintoprogram Software developer & electronics dabbler. Restoring & programming vintage computers from Acorn Atom to ZX81.
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World of Illusion is supposed to be really good. That and James Pond.
Seem to have gone to the other extreme these days. Spend a good few minutes each day playing hunt the hidden scrollbar.
Hahaha! Indeed.
Yeah, the Sharp CPU in the original is more like an 8080 than a Z80 so doesn’t have the index registers IX and IY or the alternate register set. Less suited for C than the Z80. But they’ve done it, and also the 6502, which is even less suited IMHO.
Yeah, I normally use the winding method. The Elite data is stored differently with face normals. It's more an exercise in bloody mindedness at the moment. And recalling all the relevant vector maths from years ago like dot products.
Hahaha!
Incredible! I know from experience how limited the CPU is on the DMG compared to a stock Z80.
Thanks to @markmoxon.bsky.social I * think * I understand why my backface culling routine is not quite working. I'd oversimplified my routine due to misunderstanding how the face normals worked. Shouldn't take long to fix. Job for tomorrow.
Yeah, I would assume so. That's what I'm trying to write at the moment, the optimised library, not so much a game yet. Out of curiosity, does it work on the original Gameboy?
Are you writing it mostly in C at the moment? There are obvious things I'm optimising in asm, like the line draw and using trig lookups. This is quite maths heavy, so coding in a high level language first does make a lot of sense.
Happy Birthday!!
Hahaha!
Plus I've just fixed Mrs B's laminator by giving it a hard stare.
I do really like this approach. Figuring out how the code should work in a high level language then optimising the bits that need speeding up works well with my brain. Occasionally in assembler I get stuck in the minutiae. That's the ex-8-bit games programmer in me I suppose.
And the corresponding C code now to rotate a point around 3 axis is much tighter. This in turn will be optimised into a single asm function at some point when I can be bothered.
Busy day being dad's taxi, dropping youngest off at a camp down Wrexham way. Then food and gym. Though this morning I did optimise the 3D rotation stuff so that it is now mostly in assembler. It's so much smaller and neater than the C generated code...
It's not too bad you know - there's some interest from the agencies re my skill set, and I'm doing some other stuff to fill the gaps. Plus it's nice to be a kept man for a change!
Ah yes, nothing to report.
Getting used to stack frames in z88dk this morning. I wanted to pass and return a struct (Point8 - 3 bytes). It kind of makes sense in a weird 'let's get C running on a Z80' kind of way.
Thank you! There’s more to come.
I've just released the Elite Compendium Addendum for the BBC Micro B+. It contains two bonus versions of Elite for lucky owners of the B+, including musical BBC Master Elite for the B+128. See elite.bbcelite.com/hacks/elite_... for details. #retrogaming #retrocomputing #bbcmicro #8bit #elite
It is my favourite BASIC in all incarnations, so when I was asked by Bernardo to implement BASIC on the Cerberus, I picked it. And the Agon naturally followed.
Funnily enough I'm writing Gnome Man's Sky.
Scrubbed all references to . Am using my own fastSin and fastCos asm routines that use table lookups. Still plenty of room for improvement on speed yet this has helped me iron out a couple of bugs in the maths. There's still a glitch with the back-face culling, but it's the same glitch.
Oh haha, yes I get that occasionally, and no problems.
Just read your post again - I've never had issues debugging a SNA or NEX file. I use DeZog in Visual Studio Code to handle that, and ZEsarUX/CSpect as my emulators of choice.
I'm building a NEX file.
It's sjasmplus (a Z80 assembler)
Links for downloads on this page. I'd also recommend the SDL version for a more feature rich version.
There are console mode editions of BBC BASIC on a number of platforms. I used to use it regularly on the Tatung Einstein to create lookup tables for Spectrum and Amstrad games. Modern versions are available for Linux, Windows and even MacOS. So why break the habit of a lifetime...
I'm normally up for an episode like this and there are a handful of episodes in the Star Trek universe that deal with the crew finding ancient Earth tech floating about. This episode is just the worst, mostly because of the stereotyping.
Got the ST:NG episode "Up the Long Ladder" on in the background. Completely forgot that Colm Meaney was in this episode.
Not specifically, yet. The model was available online and is instantly recognisable.
Wow!
That picture would be perfect if the adjacent kite was a bowl of petunias.
Usual Sunday shenanigans, though the chores were done yesterday so just coffee and crossword this morning.
That's really quite impressive. Handy if you've got limited desk space or are a mobile worker.
Be that guy!
I know how to greet people, order beer, and apologise, in several European languages.
I’m that guy, and if I’m not that guy, I probably know a guy who is.
Went for a nice five mile stroll with the local ramblers society around Tatton Park this morning. Wish I’d taken my big camera.
Japanese vehicles are in my experience pretty much bulletproof. We’ve had many a Toyota that have just sailed through MOTs year on year. And my Honda CB600 bike was pretty much zero maintenance.
Awesome!!
Thank you! Still a way to go with the pushing too!!
There’s a gunsmith in our village.
Wish I’d have known that earlier. The Previa that this replaced did nearly 150,000 miles before a gasket blew and took the engine out.
I think Vauxhall send a letter of sympathy.
Hahaha!
Doesn’t seem that long ago it was an uncouth youth.
I am indeed, though tend to avoid Facebook these days.
Better get my Spectrum Next out to see this running on real hardware…
It’s been a long road, getting from there to here…
A minor visual improvement this afternoon - ten minutes of coding and I've almost got hidden line removal working. Still some glitches to work through.
Yeah, I sometimes make a note on my phone. And sometimes the note still makes sense in the morning.
I'm good at solving problems in my sleep. Remember the graphics glitch I was having last night with the rotating Cobra ship from Elite that I temporarily bodged by using floats? Turns out I can use an assembler function I wrote for the clipping to do it much quicker.
Nice!
Thank you!
Forgot to mention last night that the model data was sourced from this website, courtesy of @markmoxon.bsky.social. Mark’s done a sterling job documenting the inner workings of Elite at the source level. Well worth a visit even if you don’t understand assembly language.
Okay folks, there was a quick fix - use a long in the perspective calculation and leave the rotation as int.
Ah nuts. I know that cafe well. This is the one, isn't it (not my photo).
I can switch the offending code to use floats, but as you can see, the rotation slows down somewhat. Regardless, the z88dk maths libraries are doing a sterling job there. That's done partly using floats, and sin and cos from maths.h. It'll be much faster once I've given it the asm treatment.
Hehehe!
Now its time to supercharge the 3D maths.
I think the trick is to keep printing. I usually do all my labels in one long strip and cut with scissors later. Mine gives the option to not feed once its printed one thing. As soon as you do a feed, it leaves a large gap for the cutter.
Got sick of seeing the cube. Figured it was time for an upgrade. The glitch is a maths error in the rotation, an overflow. That'll be fixed when I convert it to the optimised assembler lookup table version. Also need to do hidden face culling. The Elite data is stored differently. Easily done still.
Ah, I've got a Brother that'll take them. Might get some in for Mrs B for her teaching job. Also I know what you mean about tape wastage on them.
Oh wow! Those are fabulous!!
Not Pen Island then?
That's already done (in an earlier thread). Just need to get the filled triangles clipped. Then, get a decent model in. Getting a bit fed up staring at that old cube.
It's coming along nicely :-)
Thanks - I'll check it out later.
Thank you :-)
Cheers mate!
Oh there's hope I'll get more back then from HMRC beforehand.
That was incredibly satisfying.
Did you get tax back then whilst getting repayments? I got hammered a bit on my payment in leu of notice due to three months going out in one tax month. Be nice to get some of that back before I do a tax return.
Yeah I’m going to sign on today.
Final payment from work and my P45 arrived this morning. End of an era. The whole process I had to go through made me feel a bit grumpy. Still, onwards and upwards.
This is now more or less at the stage I got the 3D engine at originally on the 48K Spectrum. Practically game ready. I never finished it. Though it was part of my portfolio that got me my first job at Software Creations.
I’ve got this! Bought it for my eldest as a gift from his baby sister when she was born. He was really into the Teletubbies when he was a toddler. He played it on my first gen PS2. Much loved, probably got the rest of the case somewhere…
The bug, by the way, was a schoolboy error. A stackframe imbalance caused by me incorrectly declaring a parameter type as uint8_t (a byte) rather than int_t (a word). The single byte difference caused the stack frame to move by one byte every time the function was called. Mucho crasho.
Couldn't sleep last night, head full of ideas, so did a late coding session converting the clipLine routine from C to asm. There was a bug I couldn't fix, so slept on it and identified it straight away this morning. I can now start on clipping filled triangles now clipLine is in the asm domain.
I did give it a go a couple of years ago and was quite impressed with the natural language parsing of ChatGPT itself. However, as I said at the end of the video, it has no understanding of what it is doing and it looks like nothing has changed since. My reaction today would be more critical.
Ah grand, a new @curiousmarc.bsky.social video has dropped.
I've forgotten more about programming than they've learned.
This older coder is most certainly not down with so called “vibe coding”.
BBC Breakfast this morning had a long segment about the 30th anniversary of Windows 95. So what vintage computer did they put in the studio as a handy prop? #windows95
Well, everything else sucked in my day today, but the goggles were an unmitigated success.
Hahaha!
Might end up going down that route.
In other news, got fed up of my eyes being red and sore after long swimming sessions, so got some goggles.
It’s all a bit dispiriting that’s all.
Early days yet. Have applied for a couple of interesting jobs that are less speculative.
First job rejection today. It was a bit speculative, a job in the DWP, so not surprised. Got some automated feedback from them which may come in useful. Applied for a couple of other jobs.
Could not agree more with that, or him.
A good morning spent chatting with the youngest about art and this came up. Not come across chindōgu before, yet got it immediately.
It was by means of illustration, an extension of an earlier diagram. I'm not adding any horizontal edges in code, and mention earlier in the thread that clipping top and bottom is trivial.
It's quite a fun problem to solve. Took me ages to work out an efficient method from first principles many years ago, pre-internet.
I can't remember exactly how I wrote the code, though remember capping it at a handful of iterations if X didn't reach 0, and used the Y (in the example given) as a good estimate.
Probably. I think I can fudge it due to the way I'm pre-rendering the triangles.