Chuckie Egg 2023

[SamSkivington]

Hello.

I read somewhere that arcade type games probably wouldn't be well suited to being run over the Tube so I thought I'd give it a try. After all, many arcade machines work fine with multiple CPUs sharing out the workload so why not a Beeb and a co-pro? The worst that could happen is that it doesn't really work, no?

So here's a new version of Chuckie Egg, including a level editor. Requires a 2nd Processor with a 65x CPU in it.

EDIT: The files at these links were replaced with new versions that fix issues with PiTubeDirect and also ReCo6502 68516 on 07 JAN 2024

https://samskivington.com/public/beeb-d ... gg2023.ssd

https://samskivington.com/public/beeb-d ... gg2023.adl

Both discs contain the same files. ADFS loads them significantly faster than DFS.

NOTE: Versions of b-em up to and including v2.2 have issues with the Tube ULA implementation that cause this program to sit waiting for a response from the parasite straight after displaying the controls. I'm not going to try to work around that because it has been fixed in the pre-release version of b-em that I've been using during testing - https://github.com/stardot/b-em/releases/tag/m5000-filt. Hopefully v2.3 isn't too far off.



Enjoy.

[tnash]

Hi Sam, thank you for this, it's really good and I'll try it on the real beeb later.
One thing though - Harry appears to have lost his ability do to the move I'm calling the "ladder swing"...
In the original, if you hold up/right/jump together while jumping towards a ladder and keep all three held, he will immediately jump off the ladder again, almost as if he's swinging off it. In some places ( eg level 3, level 7) this can be a very effective way to get around.
How easy would it be to restore him to his full repertoire of moves?
Cheers
Tom

[SamSkivington]

Thanks tnash!

Hmmm. Interesting. Thanks for highlighting. The gameplay code is identical (untouched) from the original. This has been validated against several thousand telemetry recordings from a slightly modified (records the telemetry) version of the original too. I'll check the input code to make sure there's nothing amiss there. Thanks Again.

[SamSkivington]

I've tried this now on real hardware and a desktop computer with emulators, including jsbeeb, and what you are expecting from the key actions you have described seems to work fine.

[tnash]

Just sent you a private message - yes the jumping works fine on the real beeb so it must either be an odd keyboard or linux b-em thing.

[jms2]

Just downloaded this and had a play. It's amazing - not just because you have managed to improve Chuckie Egg, but also because this is (I think) only the second ever second processor game for the Beeb! (after Elite obviously).

I'd be interested to hear how the work is shared between the two processors. In Elite the second processor sends a stream of co-ordinates across the Tube to be plotted - so are you doing something similar here in terms of sprite movement commands? I'm guessing the game engine lives in the host whereas all the data and UI live in the parasite?

[Diminished]

This is bloody excellent.

[tricky]

Hello.

I read somewhere that arcade type games probably wouldn't be well suited to being run over the Tube ...

I would think that golden age arcade games are well suited to running over the tube as many just have memory mapped sprite x, y, no. and palette information that could be sent each frame with the beeb only needing to do the drawing, input and sound.

Most also have a charger mapped display that could be sent as updates rather than having to check the whole lot every frame as I do in most of my ports.

I have been tempted to port some more games using this setup but haven't got around to it yet!

[PJTech]

I'm really interested in this but don't have time right now to download and play it. Plus I don't have a real co-pro and my current emulator is a really old (like perhaps 8-10 years) version of b-em on Linux so it may not even work without an upgrade.

Would anybody be kind enough to share screenshots or perhaps a short video capture please?

[SamSkivington]

sent each frame with the beeb only needing to do the drawing, input and sound.

That's exactly how this works. Apart from the timing signals, the parasite runs the show and tells the host what to do on its behalf. A bit more specific than the stream of PLOT commands Elite uses but essentially the same thing.

[SamSkivington]

I'd be interested to hear how the work is shared between the two processors.

After kicking the Acorn Tube protocol out of the way, the parasite does absolutely everything from gameplay to state management and only uses the host for I/O (file access, keyboard, joysticks, sound and screen)

[BigEd]

Does it run smoother or at a higher frame rate? In any case it would be great to see a video

Well done! Could be the start of a whole new story

[SamSkivington]

It switches between 50 and 33.3fps. UI is 50fps but when you're playing the game it's the same tick rate as the original.

[BigEd]

I appreciate that the gameplay and mechanics is unchanged… wondering what might be possible though with two processors… perhaps the music could somehow take advantage???

[SamSkivington]

Not quite sure what you mean, but I was limited to two sound channels for the music because I wanted to keep the movement and egg/seed sounds in at the same time. Music 5000 was on the list of possibles but didn't make the cut.

[SamSkivington]

I made a test a while back that had raw, streamed TMS5220 speech and SN76489AN sound data in this same set-up and that worked well. I might revisit that in a future game.

[BigEd]

That could be quite something

[SamSkivington]

A handful of screenshots as requested above

[tricky]

I thought that you had a palette colour spare with 2 foreground and 4 background, but on closer inspection it looks like 1 forgetting (yellow), one midground (cyan) and 4 background, assuming you are using the palette and not sprite making + store and bgnd redraw or tile redraw.

I was wondering about nula mode 1.5 allowing 50fps, but vertical movement and moving platforms would need to move 1,1,1,2 assuming that they move 2 pixels vertically and you couldn't use the pallet trick anymore plus bad things would happen when eggs and birds overlapped!

[PJTech]

A handful of screenshots as requested above

Thank you! It looks great

[Cybershark]

Am glad you got around to the screenshots, as your initial post was very much a "soft sell" (and I honestly couldn't see what all the fuss was about). It all sounded (technically) quite brilliant but I had no idea what we were getting. I checked it out just for curiousity's sake, but maybe you should have led with this outline of the key features:

Excellent work! This really is one all-singing, all-dancing package!

[SamSkivington]

Good shout. Updated the lead post. Thank you!

[aidanthegasman]

I'm absolutely dazzled by this game Sam.

Obviously Chuckie Egg is a timeless classic; obviously the Beeb version is one of the best versions out there. And obviously, a whole bunch of people have attempted to poke it and tweak it here and there to improve it (adding a bit of colour, or adding joystick support, or designing new levels).

What you've done, however, is to basically redo the entire thing, using resources (a co-pro) which we can all emulate (sadly I don't have a hardware Tube). You've added a wealth of magnificent features. The music is perfect (who could argue with the choice of tune?) I love the Demo Mode in particular: it looks as if Henhouse Harry has some sort of AI: rather than randomly running around, he avoids the chickens and his jumps onto lifts, etc, are perfectly timed. There are only 2 ways I can think of to make this work: either you have a working AI (in which case, why limit us to 15 seconds of demo?) or each is a short, pre-recorded sequence (as in the original arcade PacMan). Can you let me know which it is?

This will undoubtedly be my default version of the game from now on, when I need my Chuckie Egg fix!

Thanks again, and I hope you have a wonderful Christmas and New Year.

[aidanthegasman]

And I still got it, baby!

[Yrrah2]

Just downloaded both .ssd and .adl version of the game to try on my real Master, but on the point "Initializing" is on the screen it stops.
And this also happens on b2.
Any suggestions? Or did I miss something on the forum?

Cheers

[Rob_hawk]

Silly question but are you using a second processor on your master?I believe it’s a second 6502 processor version. Hope I’m not wrong on that!

[Yrrah2]

Yes got the CoPro activated.
Tried on MOS 3.2 and MOS 3.5 with both 6502 and the 65C102

[Rob_hawk]

Yes got the CoPro activated.
Tried on MOS 3.2 and MOS 3.5 with both 6502 and the 65C102

I guessed you would have but thought I’d check just to be sure. Sorry I can’t offer any more help but I’m sure someone who can will be along soon!

Merry Christmas.

[Yrrah2]

No was a good question. i do make these mistakes now and then

Merry Christmas

[Rob_hawk]

No was a good question. i do make these mistakes now and then

Merry Christmas

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