cristicbz · HackerTrans

11 ปีที่แล้วdiscuss

Thanks! Uh, I'm not good at writing/saying things that are not checked by a compiler. But I'll try to write a blogpost about it.

cristicbz

11 ปีที่แล้วdiscuss

> AST based, hygenic macros, instead.

Well and generics & traits. 99% of the places where C++ programmers use templates, they would use generics in Rust. `template std::vector<T>` <-> `Vec<T>` etc.

It's only the niche metaprogramming ability of C++'s templates that would be replaced with macros.

cristicbz

11 ปีที่แล้วdiscuss

You can still trigger plenty of undefined behaviour in C++11 with no raw pointers. Just one example--iterator invalidation:

    auto v = std::vector<int> {1, 2, 3}
    for (auto x : v) {
        if (x > 0) {
            v.push_back(-x);
        }
    }

The above may segfault, do what you expect it to, run forever etc. Unchecked indexing, branching on uninitialized data etc.

Rust frees you from _all_ of these things and offers a bunch of further advantages, most notably: data race freedom. You can actually share data between threads and keep your sanity.

cristicbz

11 ปีที่แล้วdiscuss

I mean, the camera handling code is just the tip of the iceberg.

cristicbz

11 ปีที่แล้วdiscuss

I am hoping it will eventually cover game mechanics, see "Goals (subject to change)". Pull requests welcome!

cristicbz

11 ปีที่แล้วdiscuss

> How long have you worked on only this project?

It's hard to quantify how much time _this_ project took, since when I started a year ago I knew nothing about Doom or Rust. If I started writing it now from scratch, I could probably hammer it out in a working week. A better programmer could probably do it in a weekend. It's neither very big nor very hard.

But that's not how programming works, is it? In fairness, you'd need to count some of the time I spent working on a lot of other random Rust side projects and reading blog posts over the last year, while only spending a couple of hours ever other week or so on rust-doom.

> Certainly wrestled with the ownership system for a while

I think my background in modern C++ helped me a lot with this, since the "one owner per thing, move semantics" model is how you're supposed to write C++ too.

That said, figuring out the cleanest design is not easy and I'm still wrestling with it today. The code was an absolute mess last year and now it's better, but still needs plenty of work: just yesterday I decoupled WAD parsing from the rest of the code properly (https://github.com/cristicbz/rust-doom/pull/53).

I'm still learning a lot a year after dedicating all my free-time programming to Rust.

cristicbz

11 ปีที่แล้วdiscuss

I'm the author, no poo-poo-ing taken. You're completely right. The rendering code is shamelessly unoptimized indeed: doing frustum culling naively actually slows down the code because of the extra draw calls. I could probably get a boost in frame rate--by for instance memcpy-ing chunks into a dynamic buffer and keeping the single draw calls---although it already runs at 300 FPS on the integrated intel card of my laptop. So I'd rather add more features, testing and documentation than worry about perf just yet.

cristicbz

11 ปีที่แล้วdiscuss

It's the same project, I just been keeping it up to date and removed all the unsafe code. It never _needed_ unsafe code, but it was my first Rust project and I didn't know what the hell I was doing---it's now much cleaner, safer and faster than the incarnation you saw last year :)

cristicbz

12 ปีที่แล้วdiscuss

Doom I/II suggests the whole game is implemented, which isn't. But I am working on it!

cristicbz

12 ปีที่แล้วdiscuss

You're welcome! :D

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