Apollo-11
DOOM
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Apollo-11 | DOOM | |
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126 | 91 | |
56,273 | 12,516 | |
- | 2.8% | |
4.6 | 3.6 | |
19 days ago | 2 months ago | |
Assembly | C++ | |
GNU General Public License v3.0 or later | GNU General Public License v3.0 only |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
Apollo-11
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Mistral CEO confirms 'leak' of new open source AI model nearing GPT4 performance
I often like to think about https://github.com/chrislgarry/Apollo-11 as an analogy. It's public domain with available source, in the assembly language in which it was written... so it fills all the definitions of OSS!
But the process by which that code arose, the ability to modify any line and understand its impact (heh) on a real execution environment, is dependent on a massive process that required billions of dollars and thousands of the smartest people on the planet. For all intents and purposes, without that environment, it is as reliably modifiable as an executable binary in any other context - or a set of weights, in this one!
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Software Disenchantment
My more positive take on this: our runtime environments are bloated because we have ways to enable trust, stability, and iteration speeds that people wouldn't have dreamed of in years past.
Your Notion desktop app and Google Chrome both support embedding & displaying multimedia content that's controlled by people that you may not trust, but they can draw on decades of engineering to sandbox that content. They can independently be updated without worrying about a centralized `flexbox.dll` that may or may not be the right version. They do not require building a new executable to make the vast majority of UI changes. And the cost is simply storage space and initial download bandwidth.
We can look with rose-colored glasses at an era of "every byte of assembly has been hand-crafted." I, too, look in awe at what was achieved with such things as https://github.com/chrislgarry/Apollo-11/tree/master/Luminar... . But that software, per https://en.wikipedia.org/wiki/Apollo_Guidance_Computer#Softw..., took 1400 person-years of work.
We have to compare apples to apples - the abstractions we have today would not prevent such a piece of software from being built, and indeed would allow us to build that exact software, even bit-for-bit the same, much more easily due to abstractions on our tooling itself. We have not departed a world where, given a nation-state budget, one could pay for 1400 person-years of work and create the AGC (though one might make arguments about the distraction levels of modern society, but that's a different thing entirely).
But we also exist in a world where I can build and ship a cross-platform video chat application in an afternoon (well, not counting app store approvals) and be reasonably confident that my app will be compatible with, and secure on, practically any computer or mobile device sold in the past half decade, regardless of how many other apps may have been installed on each device. I'd venture to say that Apollo engineers would, and do, find this aspect of our world fascinating, too.
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Apollo dev posts backend code to Git to disprove Reddit’s claims of scrapping and inefficiency
Extension pack for picking up Matt Damon
- Analysis of Twitter algorithm code reveals social medium down-ranks tweets about Ukraine
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How much we accomplished over the years
We didn't destroy the technology. A lot of the original documentation still exists. For example, all the code for the Apollo Guidance Computer is available on GitHub if you're interested.
- A difficult decision to set us up for the future
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Discussion Thread
Can we get networking on the Apollo-11 so we can browse the DT?
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Apple Lisa source code release
It's not "just fixing typos", as this code was generated through OCR - and the publisher specifically ask to proof-read and fix typos (https://github.com/chrislgarry/Apollo-11/blob/master/CONTRIBUTING.md)
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We invested 10% to pay back tech debt; Here's what happened
> the code for the space shuttle should be written carefully
Couldn't help but remember the comments in the Apollo-11 source code saying "TEMPORARY, I HOPE HOPE HOPE".
https://github.com/chrislgarry/Apollo-11/blob/a13539c7c5c482...
DOOM
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Doom Released Under GPLv2
commercially exploit or use for any commercial purpose."
[1] https://github.com/id-Software/DOOM/commit/4eb368a960647c8cc...
This Github repo was previously released with this license:
https://github.com/id-Software/DOOM/blob/77735c3ff0772609e9c...
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GTA 5 source code leaks online
The original Doom had third-party audio playback routines, so the source came with a rewritten sound server: https://github.com/id-Software/DOOM/tree/master/sndserv
The bad news: this code only compiles and runs on linux. We couldn't
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Software Disenchantment
Here's a repo for you with no test coverage and no auto-generated DI. They using unsafe pointers all over the place, too!
https://github.com/id-Software/DOOM
Shall I prepare the postage for the letter in which you'll call John Carmack an MBA? Should we send another to Chris Sawyer? I heard he didn't even write a formal design doc for Roller Coaster Tycoon!
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Ask HN: Good practices for my first C project
cURL is one of the most used C libs and is an example of good quality C code. If you follow the style used there, see e.g. https://github.com/curl/curl/blob/master/lib/dynhds.h (and associated dynhds.c) you will be good.
Looking at the source of some of the old game-engines from the era that have since been released as open-source can also be helpful, like https://github.com/id-Software/DOOM.
In both cases notice how simple and elegant a lot of the code is. There is already enough complexity inherent in the problem they are solving, and that is where the focus should be.
Any IDE with a working language server to make it easy to jump around and refactor should work fine. Limitations might be due to the C language itself?
Error handling on such a fixed platform does not need to be super-advanced. You should always be within the confines of the system so there shouldn't be much that can go wrong. If stuff goes wrong anyway just being able call a function Fatal("FooBar failed with code 34") when unexpected stuff happens and have it log somewhere to be able to dig around should be enough. You never need to be able to recover and retry.
Make sure to use https://clang.llvm.org/docs/AddressSanitizer.html or a similar tool when developing outside of the PSOne.
That said, consider statically allocating global buffers for most stuff and avoid using the heap for most stuff.
Good luck working within the confines of the PSOne! Many hackers have pulled the hair from their head on that platform ;)
- Ask HN: Where do I find good code to read?
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Running Stable Diffusion in 260MB of RAM
Probably more easily than you'd think. DOOM is open source[1], and as GP alludes, is probably the most frequently ported game in existence, so its source code almost certainly appears multiple times in GPT-4's training set, likely alongside multiple annotated explanations.
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Some were meant for C [pdf]
I'd define an arena as the pattern where the arena itself owns N objects. So you free the arena to free all objects.
My first job was at EA working on console games (PS2, GameCube, XBox, no OS or virtual memory on any of them), and while at the time I was too junior to touch the memory allocators themselves, we were definitely not malloc-ing and freeing all the time.
It was more like you load data for the level in one stage, which creates a ton of data structures, and then you enter a loop to draw every frame quickly. There were many global variables.
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Wikipedia calls it a region, zone, arena, area, or memory context, and that seems about right:
https://en.wikipedia.org/wiki/Region-based_memory_management
It describes history from 1967 (before C was invented!) and has some good examples from Apache ("pools") and Postgres ("memory contexts").
I also just looked at these codebases:
https://github.com/mit-pdos/xv6-public (based on code from the 70's)
https://github.com/id-Software/DOOM (1997)
I looked at allocproc() in xv6, and gives you an object from a fixed global array. A lot of C code in the 80's and 90's was essentially "kernel code" in that it didn't have an OS underneath it. Embedded systems didn't run on full-fledges OSes.
DOOM tends to use a lot of what I would call "pools" -- arrays of objects of a fixed size, and that's basically what I remember from EA.
Though in g_game.c, there is definitely an arena of size 0x20000 called "demobuffer". It's used with a bump allocator.
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So I'd say
- malloc / free of individual objects was NEVER what C code looked like (aside from toy code in college)
- arena allocators were used, but global vars and pools are also very common.
- arenas are more or less wash for memory safety. they help you in some ways, but hurt you in others.
The reason C programmers don't malloc/free all the time is for speed, not memory safety. Arenas are still unsafe.
When you free an arena, you have no guarantee there's nothing that points to it anymore.
Also, something that shouldn't be underestimated is that arena allocators break tools like ASAN, which use the malloc() free() interface. This was underscored to me by writing a garbage collector -- the custom allocator "broke" ASAN, and that was actually a problem:
https://www.oilshell.org/blog/2023/01/garbage-collector.html
If you want memory safety in your C code, you should be using ASAN (dynamically instrumented allocators) and good test coverage. Arenas don't help -- they can actually hurt. An arena is a trivial idea -- the problem is more if that usage pattern actually matches your application, and apps evolve over time.
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Is it possible to see the code of 90s computer games?
Doom might be the best one, they released their code i don't remember when. It's in github if you want to check it out: link
What are some alternatives?
open-watcom-v2 - Open Watcom V2.0 - Source code repository, Wiki, Latest Binary build, Archived builds including all installers for download.
project-based-tutorials-in-c - A curated list of project-based tutorials in C
doomgeneric - Easily portable doom
luxtorpeda - Steam Play compatibility tool to run games using native Linux engines
angband - A free, single-player roguelike dungeon exploration game
microwatt - A tiny Open POWER ISA softcore written in VHDL 2008
midimonster - Multi-protocol control & translation software (ArtNet, MIDI, OSC, sACN, ...)
open-source-flash - Petition to open source Flash and Shockwave spec
vulkan-guide - Introductory guide to vulkan.
WebKit - Home of the WebKit project, the browser engine used by Safari, Mail, App Store and many other applications on macOS, iOS and Linux.
OpenSkyStacker - Multi-platform stacker for deep-sky astrophotography.
Godot - Godot Engine – Multi-platform 2D and 3D game engine