Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

A bootable CD image with a retro game in a single tweet

quaxio.com

Post reply on HN
Print view View original

51–60 of 150 posts

Re: A bootable CD image with a retro game in a single tweet

#51

Post by raphlinus »

mirimir wrote: post #18
barbegal wrote: post #4

I was confused as to how you could represent a bootable CD image in printable characters. It turns out that you can't. This is a tweet of a perl script which creates a cd.iso file that you can then boot from. The perl script significantly decompresses the data in the tweet. That said, this is a playable game in around 60 bytes of actual data which is impressive.

I'm reminded of the RSA in Perl "weapon" t-shirt :) https://upload.wikimedia.org/wikipedia/commons/9/96/Munition...

Machine readable as well as machine washable[0]!

[0]: http://cypherpunks.venona.com/archive/1995/10/msg00317.html

Re: A bootable CD image with a retro game in a single tweet

#52

Post by cheeze »

mirimir wrote: post #18
barbegal wrote: post #4

I was confused as to how you could represent a bootable CD image in printable characters. It turns out that you can't. This is a tweet of a perl script which creates a cd.iso file that you can then boot from. The perl script significantly decompresses the data in the tweet. That said, this is a playable game in around 60 bytes of actual data which is impressive.

I'm reminded of the RSA in Perl "weapon" t-shirt :) https://upload.wikimedia.org/wikipedia/commons/9/96/Munition...

Man that shirt is awesome... But man I would never wear that shirt as that looks like the crown jewel of any neckbeards collection

Re: A bootable CD image with a retro game in a single tweet

#53

Post by tomcam »

komali2 wrote: post #48

This is the second time this week I've seen someone note that ISO standards are expensive - are they copyrighted or something? Why doesn't someone just publish them online for free?

Yes, they are copyrighted. The link to article points to this equivalent, free ECMA 119 standard: https://www.quaxio.com/files/2018/bootable_cd_retro_game_twe...

Re: A bootable CD image with a retro game in a single tweet

#54

Post by amenghra »

tomxor wrote: post #50

Looks like the turbo button needs to be in the on position for this one: 0.05 FPS in a qemu KVM on my old P8600... I presume the game loop uses the hardware clock :P btw my base64 util needed lower case -d

There’s a comment on the page.

For some reason, emulators (at least the ones I tried) wait 4x what real machines wait when you use BIOS int 15b 86h. You can tweak the code if you want to play at a faster speed.

There’s probably a sound explanation for this discrepancy...

Re: A bootable CD image with a retro game in a single tweet

#55

Post by amenghra »

Klathmon wrote: post #43

Man I love these things. Back before Twitter upped their character limits, I remember a trick to cram more data in a tweet was to abuse how Twitter counts characters (it attempts to count visually rather than by byte), so by using a ton of multipart emojis or larger Unicode characters to over double the information that could fit in a tweet.

I thought about using Unicode, but it felt like cheating.

Perhaps someone can fit two games in a single multibyte tweet?

Re: A bootable CD image with a retro game in a single tweet

#56

Post by amenghra »

a1k0n wrote: post #24

Hats off for making use of the AAA instruction. That's a very clever sequence converting up/down/left/right to -320/+320/-1/+1.

For those who don’t know, x86 had support for binary coded decimal (you end up wasting a bunch of bits).

AAA converts the result of the addition of two valid unpacked BCD digits to a valid 2-digit BCD number.

Re: A bootable CD image with a retro game in a single tweet

#57

Post by Klathmon »

amenghra wrote: post #55
Klathmon wrote: post #43

Man I love these things. Back before Twitter upped their character limits, I remember a trick to cram more data in a tweet was to abuse how Twitter counts characters (it attempts to count visually rather than by byte), so by using a ton of multipart emojis or larger Unicode characters to over double the information that could fit in a tweet.

I thought about using Unicode, but it felt like cheating. Perhaps someone can fit two games in a single multibyte tweet?

IIRC weren't the Twitter length changes only applied to languages that weren't benefiting from the more "dense" encodings.

Meaning languages like Chinese and Japanese are still at the old limit.

Re: A bootable CD image with a retro game in a single tweet

#58

Post by jobu »

This reminds me a bit of the science of nanoinformatics as described in one of the Expanse novellas (The Vital Abyss):

"A thought experiment from my first course in the program: Take a bar of metal and put a single notch in it. The two lengths thus defined have a relationship that can be expressed as the ratio between them. In theory, therefore, any rational number can be expressed with a single mark on a bar of metal. Using a simple alphabetic code, a mark that calculated to a ratio of.12152205 could be read as 12-15-22-05, or “l-o-v-e.” The complete plays of Shakespeare could be written in a single mark, if it were possible to measure accurately enough. Or the machine language expression of the most advanced expert systems, though by then the notch might be small enough that Planck’s constant got in the way. How massive amounts of information could be expressed in and retrieved from infinitesimal objects was the driving concern of my college years."

Pure fiction at this point, but it would be an interesting experiment to encode data into objects that could be expressed using the mathematical ratio of their shapes or sizes.

Re: A bootable CD image with a retro game in a single tweet

#59

Post by dfcarney »

jobu wrote: post #58

This reminds me a bit of the science of nanoinformatics as described in one of the Expanse novellas (The Vital Abyss): " A thought experiment from my first course in the program: Take a bar of metal and put a single notch in it. The two lengths thus defined have a relationship that can be expressed as the ratio between them. In theory, therefore, any rational number can be expressed with a single mark on a bar of met…

Check out Arithmetic Coding: https://en.m.wikipedia.org/wiki/Arithmetic_coding

Re: A bootable CD image with a retro game in a single tweet

#60

Post by mlindner »

barbegal wrote: post #4

I was confused as to how you could represent a bootable CD image in printable characters. It turns out that you can't. This is a tweet of a perl script which creates a cd.iso file that you can then boot from. The perl script significantly decompresses the data in the tweet. That said, this is a playable game in around 60 bytes of actual data which is impressive.

Perl isn't doing any decompression. The data is just stored in base64 encoding.
Post reply on HN