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Comment by 5trokerac3 | Hacker News Reader

I would love to see this demo ported to an 8 bit computer

I'm waiting for the 3270 version.

I don't think any eighties 8-bit computer has any hope rendering this.

A Commodore 64 or TI-994A could. Probably not at 60fps, but it could be done. It would definitely need to be done in assembly, or with a modern compilation tool, like cc65.

The sprites would have to be hardcoded, instead of being interpreted from images. You would also have to be extra smart about what you're calculating/rendering, but keep in mind that your screen is probably only 40 characters wide, so the amount to render is exponentially smaller.

You'd be amazed what can be done on those older computers when the developer understands how the processors work on the ground level.

At the very least it'd be an impressive tech demo for something like the Commander X16[0], a new 6502 based computer running at 8mhz.

[0] https://github.com/commanderx16

> A Commodore 64 or TI-994A could. Probably not at 60fps, but it could be done. It would definitely need to be done in assembly, or with a modern compilation tool, like cc65.

Well, I was programming on C64 way back, and am pretty much aware what the system can and can't do. Sprite crunchers, xor filled vector fillers, etc. are familiar to me.

Cc65 would only hurt the effort. You need a full spectrum of assembler tricks to get any kind of performance out of C64.

C64 (PAL) has just 19k clock cycles available per 50 Hz frame. Since fastest instructions are 2 cycles, that's at most 9.5k instructions. Realistically closer to 5-7k. No multiply (hello table lookups!), no divide and not even 16-bit add.

Or in other words, it takes maybe 10k+ cycles for C64 to just "memcpy" 1000 bytes of characters!

You could implement something like Asciicker in a limited demo... but it'd be more like a souped up video player. Which, sadly, is a rather common technique in recent C64 demos, but understandable due to the limitations.

There were realtime 3D games on 8-bit machines. The framerates were atrocious, and they used wireframes or simple filled polygons, but they were also higher-resolution. The C64's character display is 40x25, so that's only 1000 "pixels" per frame.

I think it could be done, with reasonable sacrifices.

> I think it could be done, with reasonable sacrifices.

Yeah, like dropping rotation. I think it'd be easier to do 80x50 rendering than ASCII.

> The framerates were atrocious...

That's the sacrifice you'd need to make.

I don't think anyone's saying you could do a cycle-perfect emulation on 8-bit. The framerate would be low, the terrain mesh would have to be much simpler. But The Sentinel[1] ran on C64 with acceptable framerates (better than a lot of 3D games with much simpler graphics). I think you could manage a perfectly satisfactory port of Asciiker, even with rotation.

[1] https://www.youtube.com/watch?v=D2H8WbDo5SE

Are you joking? The Sentinel takes 6-8 seconds to render a scene. The rest is just very clever 2D-scrolling and selective object insertion and removal.

Geoff Crammond (author of The Sentinel) wrote another game that's graphically way more impressive in this context: C64 Stunt Car Racer. https://www.youtube.com/watch?v=KMgjmIW8fd8

This is not to say The Sentinel wasn't an amazing game in all aspects, including graphically. It certainly was.

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