Demo THE CURE (Was: Dot-matrix engine for AGA)

[saimo]

In the past months I've been thinking of some new game concept that would finally put my dot-matrix engine for AGA Amigas to good use. Admittedly, I haven't come up with anything worthy yet, but I've been doing some technical experiments. I thought you might fancy having a look at the latest experiment:

https://www.youtube.com/watch?v=LE8FyrxEhnQ

Details:

• the parallax is not obtained by means of pre-rendered separate lines, but by applying perspective to a rectangular texture; this means that the texture can be easily modified/animated on the fly, and also that it doesn't have a size limit;
• the shadow is not made of a number of precalculated frames, but it's a single bitmap that gets cast in perspective (exploiting the parallax effect) and also with a pseudo-antialias effect;
• the scrolling is not obtained by changing bitplane pointers, but by redrawing the whole screen: while this steals quite some bandwidth, it allows for a single raster (thus making rendering operations really easy) and eliminates the need to keep/restore dirty regions;
• the character is not a bitmap, but it's made of 1200 separate dots (which is what allows it to transform into any other shape made of the same 1200 dots);
• an unexpanded A1200 runs this at full speed (i.e. 50 Hz); it would do so even if there were a second 1200 dots character, although there wouldn't be time to do much more - to gain extra time for an actual game, characters should be plain bitmaps and, if needed, the parallax area could be made a little shorter.

Note that I'm NOT going to make a beat'em up. Again, this is just an experiment.

(The graphics have been derived from assets which are the property of Capcom Co., Ltd.)

Previous video:

https://www.youtube.com/watch?v=mB6wgJbj0Gg

[saimo]

@F1Lupo

Thank you


@golem

Looks really good.

Thanks!

My mind boggles at the maths that must be behind that.

Nothing particularly special, to be honest.

[saimo]

This video shows a stock Amiga 1200 running various visual effects using the dot-matrix engine. The effects are obtained by means of a system that allows every single pixel to be located anywhere in memory (regardless of the RAM type). Lately, I've started thinking again of a game that makes use of the dot-matrix engine, and I came up with this new system. I finally have a somewhat interesting game concept (not shown here), but I'm still thinking of better alternatives.
Technical note: while the dot-matrix engine doesn't require any CPU operation, this new system is entirely CPU-driven, so each screen update takes more or less 1.3 frames on a stock A1200; therefore, if the game eventually uses the system, it will run at most at 25 fps.

https://www.youtube.com/watch?v=jSvJmn0-KoE

[saimo]

Would be cool as a native video format too - movie.dmv, dot-matrix video

Well, conceptually, the only difference with any existing format is that the depth is just 2 bits. Anyway, boooring

[saimo]

Two more experiments: https://www.youtube.com/watch?v=cH20N0D5kKw

For convenience, these are the previous videos:
 * https://www.youtube.com/watch?v=mB6wgJbj0Gg
 * https://www.youtube.com/watch?v=LE8FyrxEhnQ
 * https://www.youtube.com/watch?v=jSvJmn0-KoE

[saimo]

Reprise of the spaceship-travelling-through-tunnel idea: https://www.youtube.com/watch?v=Be94FYcr1Oc

The tunnel renders in about:
 * 1.1 frames on a stock Amiga 1200 (I must say I'm quite disappointed I just can't make it take less than 1 frame);
 * 0.28  frames on an Amiga 1200 + Blizzard 1230-IV with 60 ns RAM (the machine used to record the video).

Previous videos:
 * https://www.youtube.com/watch?v=mB6wgJbj0Gg
 * https://www.youtube.com/watch?v=LE8FyrxEhnQ
 * https://www.youtube.com/watch?v=jSvJmn0-KoE
 * https://www.youtube.com/watch?v=cH20N0D5kKw

[saimo]

I managed to get the effect to run in less than one frame also on a stock Amiga 1200. I was trying to be too smart, so I thought I'd try to dumb the code down... and it worked! The time needed to render the tunnel went from ~1.1 frames (~22 ms) to ~0.937 frames (~18.74 ms). On the other hand, unsurprisingly, the simplified code performs worse on expanded machines: on an Amiga 1200 with Blizzard 1230-IV with 60 ns RAM, it went from ~0.28 frames (~5.6 ms) to ~0.48 frames (~9.52 ms).

This video shows the effect running on a stock Amiga 1200. The second part shows visually the rendering time: the blue blackground represents the part of a frame (the whole screen + vertical blanking area) taken by the the tunnel rendering; in other words, the non-blue blackground represents the unused time of a frame.

https://www.youtube.com/watch?v=DCvqD-35_zE

Previous videos:
 * https://www.youtube.com/watch?v=Be94FYcr1Oc
 * https://www.youtube.com/watch?v=mB6wgJbj0Gg
 * https://www.youtube.com/watch?v=LE8FyrxEhnQ
 * https://www.youtube.com/watch?v=jSvJmn0-KoE
 * https://www.youtube.com/watch?v=cH20N0D5kKw

[saimo]

Eventually I used the engine to make a demo. It got released at the Solskogen 2020 demoparty about 1 hour ago. Feel free to watch/download it from https://www.retream.com/THE_CURE (running it on a real Amiga is mandatory to really appreciate it, as a video, due to technical reasons, just doesn't cut it)
The demo comes with a README that explains all the details, including why I dropped the idea of a making game and went for a demo, instead.

[saimo]

Thanks, lionstorm!
You'll definitely enjoy it more on your machine, as the visuals of the demo are unsuitable for videos.

[saimo]

Really lovely demo--looks like a marvelous technical achievement and the messaging is on point. Congrats!

Thank you!

I think there still must be a game somewhere in that engine... even if you haven't found it yet. Give yourself a well-deserved break and maybe the idea will come to you when you least expect it.

Nope, it just isn't suitable. But I already have 2 other engines that are waiting to be made use of for games, and I'm already working on that

[saimo]

I've been asked a few times to release the music separately, and finally I got around to do it! Here it is:

https://soundcloud.com/retream/the-cure

(The quality is higher than in the demo itself due to the limitations of the Amiga hardware - for details, check out the "About the music" post in the Community section of the demo page.)

And sorry for the delay

[saimo]

I just found out that the demo earned me a nomination in the New Talent category of The Meteoriks 2021 (that's the demoscene equivalent of the Oscars)

Nominees presentation: https://youtube.com/watch?v=lyaTR13RxmQ
Meteoriks 2021 website: https://2021.meteoriks.org/nominees
THE CURE webpage: https://retream.itch.io/the-cure
THE CURE video: https://www.youtube.com/watch?v=qgg90MCJKok

[saimo]

Lately I realized I could make the startup and cleanup code of SkillGrid more robust, so I improved it further. I decided to apply the same improvements to my other productions, and today it was THE CURE's turn...

v1.1 (20210602)
* Made startup and cleanup code more robust.
* Fixed (unlikely) memory leak in cleanup code.
* Replaced "actual" with "current" in standings graphics.
* Fixed/improved README.

The new version is available for free download from https://www.retream.com/THE_CURE.

[saimo]

Such words are much appreciated. Thanks for the lovely feedback!

[saimo]

Just released a slightly revised version.

v1.2 (04.08.2021)
* Made startup and cleanup code more robust.
* Made a few tiny optimizations.

https://www.retream.com/THE_CURE