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Show HN: My hobby OS that runs Minecraft

astral-os.org

236 pointsavaliosdev33 comments

> due to the mlibc code using the char value from the format string, the values above 127 passed by OpenJDK would be handled as negative integers

It's 2025 and I still don't get why Java needed signed chars and bytes. Why completely disregard the convenience of using them for array access/etc..

Java creators tried to avoid giving developers any sharp edges. Interactions between signed and unsigned integers can be surprising, so they disallowed unsigned integers.

Of course, not having access to unsigned quantities makes interaction with other programs difficult :(

The one that annoys me is that people think implicit type conversions are dangerous for some reason, so they also disallowed `char a = 10; short b = a;` without writing a cast even though this makes no sense.

It feels like "sharp edges" often means "I once had a horrible bug due to accidentally misusing this". But if you cut features based on that definition, you'd soon have an empty programming language.

Java was apparently quite successful, though. So maybe they got the balance right for their goal?

I'd like a 10pples please.

The signedness of `char` is implementation-defined, it is signed on x86 but unsigned on ARM. So assigning a plain char to a wider integer type is suspicious, did the programmer expect sign-extension or zero-extension?

It's not implementation-defined in Java because there aren't any unsigned types.

Personally I think explicit typecasts are even more suspicious, because introducing explicit semantics is worse than implicit semantics if the explicit ones are wrong.

> Java creators tried to avoid giving developers any sharp edges.

They failed.

Well, I'd argue they created a straight jacket. That prevents a number of self harm tactics. It also makes a lot of easy things pretty hard to do.

Easy,

> Gosling: For me as a language designer, which I don't really count myself as these days, what "simple" really ended up meaning was could I expect J. Random Developer to hold the spec in his head. That definition says that, for instance, Java isn't -- and in fact a lot of these languages end up with a lot of corner cases, things that nobody really understands. Quiz any C developer about unsigned, and pretty soon you discover that almost no C developers actually understand what goes on with unsigned, what unsigned arithmetic is. Things like that made C complex. The language part of Java is, I think, pretty simple. The libraries you have to look up.

From http://www.gotw.ca/publications/c_family_interview.htm

Note that Java has unsigned support nowadays, only not as primitive types, although this is considered post Valhala.

For example, https://docs.oracle.com/en/java/javase/25/docs/api/java.base...

That's quite a milestone and achievement, well done! Your current Features list reads far beyond hobby level! It certainly puts my own hobby phone OS to shame. I'm still working out touch screen driver, and I only have IBM/437 bitmap fonts so far, which turned out to be far too small for these modern phone screens, for surely it cant be my tired old eyes...

Can I ask how you keep yourself motivated on such a complex, large and difficult project? This week I have been bogged down in I2C support and find myself wondering if I'll ever reach the next level.

Of course hard projects have their own special rewards, seeing that first pixel appear on screen was a magical moment, and felt like real programming again, especially compared to all these huge modern complex multi-layered software stacks.

Sometimes I take long breaks but I always end up coming back. I find doing multiple things in my projects at the same time to help me not burn out as easily.

Thanks. Well your post motivated me to knock off the rest of the I2C yesterday.

Good luck with the rest of your project.

Well done and thanks for sharing, it's great to see people making a hobby OS and it's awesome that it plays Minecraft! How long have you been working on Astral?

The initial commit on the Github page was on April 2023, so at least that long methinks.

Hi, this iteration I have been working on since 2023, but it uses some code in some places from the old iteration which I was working on during 2022 and 2023

great job, bet you learned some really cool stuff along the way!

Love the Motif-style window borders!

Indeed! Looks like it uses a port of https://github.com/fvwmorg/fvwm3

The “Astral from scratch guide“ idea really caught my eye.

Gotta say that would be a pretty cool evolution of DIY electronics kits to OS kits

I love hobby OS projects, and it's good to see how many there continue to be posted here. I can never get enough! It looks like this one has some networking support as well.

This is very impressive! When I saw the title, I thought it would be classicube, but no, it's actual minecraft.

Indeed. Now modern minecraft (1.20) and even modded (GTNH) is working as well.

Excellent work.

Now all we need to do is run your OS on a redstone virtual machine inside of Minecraft, then run Minecraft on it. That way you'll have Minecraft inside your Minecraft.

Better than Windows 11 already. I can't run Bedrock or Java without first signing into the Microsoft Store on "my" PC.

Good news, you too can run Minecraft Alpha 1.2.0 single player offline without signing in. That's not what made this impressive :).

Try the "Windows Legacy" launcher, or a 3rd party launcher like PrismLauncher. The legacy launcher is made for Windows 7 and is directly equivalent to the macOS/Linux launcher, so it doesn't have a hard dependency on the Microsoft Store. It will probably be a while before they stop maintaining it because it's such a trivial port.

Excellent work! And very much in the spirit of the HM ethos.

Congrats! Seeing an old version of MC makes me nostalgic.

I would be interested in a benchmark.

Very inspiring!

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