Reviving Old X Code

by fcambus • 6 years ago

247 55 6 years ago

Note: the author is Keith Packard, who wrote a ton of the original X Window System code. I adored that system! The idea of running graphical code on multiple machines, then displaying the results locally, has yet to be surpassed.

"In 2011, O'Reilly awarded an open source award to Packard, as "the person behind most of the improvements made on the open source desktop in the last ten years at least."" -- https://en.wikipedia.org/wiki/Keith_Packard

pjmlp• 6 years ago

I attended a couple of FOSDEM talks from him, very nice experience.

swiley• 6 years ago

My understanding is that X11 documentation was how O'Reilly got started. It's fantastic that 20 years later they're still celebrating the authors and maintainers.

pengaru• 6 years ago

Keith has been super friendly and supportive in my experience. Back when I started working on a compositing window manager something like a decade ago, I used his xcompmgr as a reference and he was always responsive and helpful whenever I emailed him questions about it.

gspr• 6 years ago

His talks are also delightful. Extremely brilliant people like him often either have quirks or are not the greatest speakers (don't get me wrong – I don't expect a single human to have every skill), but Packard seems to excel at everything: he's obviously a brilliant engineer, he's a wonderful speaker, he seems to be an all-around pleasant and friendly human, he seems to manage a sane and healthy personal and family life. Just a stellar person!

The single fact that he's doing RISC-V work at SiFive boosts my confidence in what they're doing.

skohan• 6 years ago

The idea of running graphical code on multiple machines, then displaying the results locally

What does this mean? It's like a remote desktop or something?

PeterisP• 6 years ago

"Remote app" instead of remote desktop would be a better analogy.

You run code on multiple machines (which might not even have any graphics devices or the concept of a "desktop" there) where each program might display graphical results in windows on your machine.

convolvatron• 6 years ago

yes, except its up a layer. remote desktop moves pixels, and X is a protocol that distributes the rendering api.

so you start up your app, and query what kind of display you're connected to - there is all kind of cruft about color models and bitplane depths. choose fonts, register for events (mouse, resize, etc), draw your elements and wait for the user to interact with you.

it makes absolute sense in the context of the early 90s 'lets make this a network api' - and almost none from a modern perspective

as bloated as the browser model is, i think shipping code to run on the users machine is a much more powerful model... if you can keep it small and deal with the security issues.

exikyut2• 6 years ago

X is a native remote desktop system. It just happens that we generally all run our apps on the same machine as where X runs, nowadays.

Sadly playing around and learning how it works is trickier than it used to be now that X doesn't listen over TCP by default (...because the protocol is unencrypted and unauthenticated... can't argue there), but google "SSH X forwarding" for a reasonable startpoint that's still fairly universally supported (you can even get X servers for Windows that work with PuTTY, and it all works natively on Linux and macOS).

tmountain• 6 years ago

Been a Keith Packard fan since the 90s. He's an incredible contributor, and his body of work speaks for itself.

kiddico• 6 years ago

I'm not saying we're going to bring this guy's site down... but we're totally going to bring this guy's site down.

Just going to leave this right here... https://web.archive.org/web/20210103182219/https://keithp.co...

MaxLeiter• 6 years ago

Good call, it’s down for me. Thanks!

garaetjjte• 6 years ago

Imagine trying to build Windows or Mac OS code from the early 90's on a modern OS...

I guess, in Windows case it also should be relatively easy?

badsectoracula3• 6 years ago

Yeah, though pure X11 code should still be easier (ignoring anything not related to the APIs at hand of course, like the assumptions the existing code had about 32bit-ness) since the API hasn't changed at all. Win16 vs Win32 is 99% the same, but there are still a few minor differences, like some changes in how WPARAM (which was now 32bit) was interpreted in a few messages.

Mac OS would be a complete rewrite though, no salvaging that.

p_l2• 6 years ago

Early 1990s X11 clients are sometimes broken on recent X.Org setups in my experience, in subtle ways usually involving keyboard.

And that's assuming running under X.Org.

As for Win32, if the application didn't do stupid things like setting bitflags that were "reserved for future use", things apparently work without recompile for basic GUI from 1.01 to Windows 10.

mattl• 6 years ago

Mac OS would be a complete rewrite though, no salvaging that.

I bet you could get a NeXT application from the early 90s running without too much pain.

phendrenad2• 6 years ago

It's really amazing that win32 has remained unchanged for so long. I guess they got it right the first time (or rather, Palo Alto Research Centre got it right the first time). And if it ain't broke, don't fix it.

dbremner• 6 years ago

Porting 16-bit assembly is harder but porting C code from Win16 to Win32 is pretty easy.

https://github.com/dbremner/cake is a 16-bit Windows 1.0 application that I ported to Win64; most of the changes weren't required.

blinkingled2• 6 years ago

TL:DR version - People who love programming are not shy or afraid of going from just needing to update copyrights to converting K&R to ANSI-C, fixing pointer bugs, adding new widgets and even finding new card images in SVG to make it look all better! Hope these KGames updates land in Debian unstable soon.

Also I wondered from the headline why keithp is into XCode - might be better to have used X11 code instead.

martyvis• 6 years ago

Some of the code was from X10!

blinkingled2• 6 years ago

A very basic port to X11 was done at some point, and that's what Debian has in the archive today

So, no?

type0• 6 years ago

Also I wondered from the headline why keithp is into XCode

Yeah, dismissed it first thinking it was about appleIDE, really glad it dawned on me it's about X, good article.

babkayaga• 6 years ago

live xmille, great job keith!

one if the new cards says vehicle prioritaire. given card names are in French should be vehicule prioritaire i guess....

makapuf• 6 years ago

Or even véhicule prioritaire.

drewg123• 6 years ago

A few years ago, I rebuilt my projects from my undergrad graphics class in 1991. They were written on 32-bit Decstations running ULTRIX, and worked after only a few changes on FreeBSD/amd64. Most of the changes were actually just to fix up some header file includes. I was surprised that that they worked just fine.

Lammy• 6 years ago

I've never seen a UI described as "rustic" before, but I love it.

bartvk• 6 years ago

He's a pretty good writer. To me, it read as a feel-good programmer story. I loved reading it.

skissane3• 6 years ago

Looking at bug – https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=974011 – there is all this talk about copyright of the xmille and mille computer programs, I don't see any discussion of the question of the copyright of the underlying card game.

Mille Bornes was invented by Arthur Dujardin (using pen name Edmond Dujardin), illustrated by Joseph Le Callennec, and first released in 1954 [0]. Dujardin died in 1964 [1], so using EU copyright term of author's life + 70 years, its copyright would expire in 2034. Le Callennec died in 1988, so copyright on the original illustrations would expire in 2058. (I don't know how dependent the illustrations in the computer game are on the original.)

I'm not sure who currently owns the copyrights to the original card game. But Dujardin founded the Dujardin company which still sells Mille Bornes [3] so I would assume they still do. Since 2007, the Dujardin company has been owned by the French TV network TF1 [4].

The copyright owners to the card game have probably never heard of this obscure non-commercial computer game. Who knows if they'd react to it indulgently or not.

[0] https://en.wikipedia.org/wiki/Mille_Bornes but actually the French article has a lot more information: https://fr.wikipedia.org/wiki/1000_bornes

[1] https://fr.wikipedia.org/wiki/Edmond_Dujardin

[2] https://fr.wikipedia.org/wiki/Joseph_Le_Callennec

[3] https://www.jeuxdujardin.fr/produit/milles-bornes-pegboardab...

[4] https://fr.wikipedia.org/wiki/Dujardin_(%C3%A9diteur)

twic• 6 years ago

I believe that game mechanics are not copyrightable. The text and artwork are, but not the rules themselves.

My dad has a naval-themed clone of Milles Borne, which we played a lot when I was a kid:

https://boardgamegeek.com/boardgame/6806/nautic-miles

I liked it so much that when we had a school project to make a game, I made a space themed clone of that!

tjader• 6 years ago

IANAL, but I don't think games are copyrightable per se. You may have a registered tradermark on the name an logo, you have copyright over the specific artwork and text in the game, and you may have a patent in some specific mechanics of the game, but the game itself is not covered by copyright.

skissane3• 6 years ago

IANAL, but I don't think games are copyrightable per se

IANAL either, and you may well be right, but maybe this is the sort of question in which the answer may depend on which country's laws we are talking about? Even if what you say is true in country X, it might not be true in country Y.

You may have a registered tradermark on the name an logo

Indeed, Dujardin SAS owns a registered US trademark on the phrase "MILLE BORNES" for a card game – https://tsdr.uspto.gov/#caseNumber=72156515&caseType=SERIAL_... – applied 1962, granted 1965, last renewed in 2015 (up for renewal again in 2025).

I don't know whether a registered trademark on a physical card game applies to a computer version of it, but I would suspect it does.

bronson• 6 years ago

According to Wikipedia, Mille Bornes is almost identical to Touring, a card game first produced in 1906.

https://en.wikipedia.org/wiki/Touring_(card_game)

taviso• 6 years ago

Funny, he mentions the Xaw fonts, I was just looking at something similar. I've been using XTerm with Xft support for years but never really thought about it, how come the text in the menus and toolbars is so crunchy?

I eventually tracked it down, Xaw3dXft operates in compatibility mode by default. A oneline patch enables all the new features, and makes a world of difference.

Here's a screenshot, I think it's night and day: https://twitter.com/taviso/status/1344779126767435776

I mailed a patch to the maintainer, hopefully the next version will fix it!

pram• 6 years ago

I'm more surprised anyone is actually maintaining Xaw lol. Does Athena even use it anymore?

fsckboy• 6 years ago

it looks better, but why did they add all that whitespace? yecch

Jkvngt• 6 years ago

I've been building ANCIENT Unix programs from the tuhs site, almost everything just works on modern Debian. Even the odd X11 program builds and runs fine.

MayeulC• 6 years ago

I'm wondering a few things regarding network transparency:

- Are vector graphics drawn by the X toolkit, or is the bitmap transferred in uncompressed form to the X server for drawing?

- The same regarding antialiased fonts: does the antialiasing happen at the client, or the server-side?

I would tend to guess that both happen at the client side, which ends up transferring bitmaps to the server. There's hardly any advantage to X's architecture if you end up transferring bitmaps...

sprash4• 6 years ago

Since he is using the Cairo library everything is rendered locally and transferred in uncompressed form to the X server for drawing. The same is true for all font engines which use in the case of Xft the Xrender extension.

I never understood why they didn't include proper font rendering and Cairo into the server. This would not only solve a lot of issues like mixed dpi rendering and vastly improve network transparency but would also eradicate duplicate effort and fragmentation in the toolkit space.

lmz• 6 years ago

What would be the fallback in your world if the server didn't support the new ops? If the fallback is client rendering, why would anyone want to risk using the (unknown) server implementation when they can just rely on the same (and tested) client code everywhere?

cycloptic4• 6 years ago

Since he is using the Cairo library everything is rendered locally and transferred in uncompressed form to the X server for drawing. The same is true for all font engines which use in the case of Xft the Xrender extension.

So this is not necessarily true, it depends on how you're using Cairo. If you're using Cairo's xlib surfaces, those will try to accelerate with XRender if that's available: https://cairographics.org/manual/cairo-XLib-Surfaces.html

As far as why the toolkits never got on board with it, some do actually use XRender in certain circumstances, but it's hard for all applications to make use of it properly. Most of the advantages go away if you have any images coming down the pipeline at all, or if you need to do any text layout or reading back from the pixmap, or if you have any GL/Vulkan usage in your application, etc. Plus historically I've heard the implementation of this was very inconsistent and on some servers it actually resulted in a slower rendering path, although this should not necessarily be the case if you're using the current Xorg with glamor enabled.

Reviving Old X Code

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