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geysersam | on: Zig Structs of Arrays (2024)
Genuine question: why do you think game engines need operator overloading? I mean, what's wrong with generic functions like add, multiply, dot etc.
aaaashley | parent | next
Not GP, but I've written game engines and rendering engines. Vector operations are just common enough that having to write `.mul` every time is a huge pain, especially when you put many of them together for a large formula. Compare:

(physics_data.velocity + omega * change) * frame_delta_time

to

physics_data.velocity.add(omega.mul(change)).mul(frame_delta_time)

We learn to read and think about math a certain way, which is incompatible with Zig. Also, Zig's design philosophy of "reading code over writing code" is incompatible with the kind of small modification-test-cycles required when doing games, and creative programming in general. So Zig is sort of DOA anyway for that kind of thing.

But I've been using Zig for non-game projects and it's been fantastic, so definitely not "Blind leading the blind" for the overall language design, imo.

smj-edison | root | parent
I've been thinking about a way around this, and I'd be interested to see if comptime with a DSL wouldn't be too unwieldy. Something like

  math("(v + Ω * c) * Δt", .{ .v = physics_data.velocity, .@"Ω" = omega, .c = change, .@"Δt" = frame_delta_time})
I know this is already possible with comptime, though I haven't implemented it yet since I haven't needed vector math in what I'm working on currently. Can't decide whether using math names is better or worse than using the full variable names though.
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hmry | parent
Why have operators at all?

  x = x.add(step.mul(2)).mod(width)
Or in C

  x = imod(iadd(x, imul(step, 2)), width)
vs

  x = (x + 2*step) % width
For me the answer is very simple: Operators make it easier to read the code which makes it easier to spot bugs. It also makes it easier to turn formulas from textbooks into code.

If 50% of the code you're working with is using vectors and matrices, not having operators for those parts is quite annoying.

Note that you can have vector operators without overloading, e.g. Odin has built in vector and matrix types.

But personally I think it's better to give the user more power instead of only letting the compiler author pick which types to allow operators on. Like how Java overloads + but only on the String class. Why do they get to do it, but not me?

applfanboysbgon | root | parent | next
Woah there, "=" is an operator! I'm afraid you're going to have to go to jail for using an operator in a no-operator zone.
dnautics | root | parent | next
you actually don't want "operator overloading", you want syntactic sugar. I once proposed just a special operator syntax at the parser level, but it got rejected, but if you REALLY wanted it, you could probably do this in about 100-120 lines as a fork of the zig compiler, just hacking (a <_> b) as a special form to be transformed into @"<_>"(a, b). Requiring parentheses elides questions about operator precedence.

    const @"<+>" = @import("operator_module").plus;

    ...

    const x = (a <+> b);
Decabytes | root | parent
> Why have operators at all?

I mean as an avid Lisp fan, I feel like Lisp basically answers the question of how much syntax you need in a langauge. I must admit though, not having to deal with operators precedence is really nice

  (mod (+ x (* 2 step)) width)