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C++ vs. OCaml: Ray tracer comparison (2005)

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Re: C++ vs. OCaml: Ray tracer comparison (2005)

#2

Post by chollida1 »

I work on a project that's a mix of F# and C++ and my code tends to break down very similarly to this.

The actual algorithmic lines are very similar in size and readability but when it comes to defining your data structures, F#/OCaml clearly wins.

The author of the website(Jon Harrop) is a very good writer and though his books are expensive I'd recommend them to anyone learning OCaml or F#.

Specifically F#/OCaml for scientists is awesome( it comes in variants for both languages) as is F# for Numerics.

Re: C++ vs. OCaml: Ray tracer comparison (2005)

#3

Post by tacos »

And now's a perfect time to reflect on how the two languages evolved during the past decade. C++ obviously moved forward quite a bit -- cleaning up the loop constructs in particular.

OCaml? Uh... there's F# for realists, Scheme for optimists, and Haskell for pedants. If you're actually writing OCaml web apps in OWebl I'd sure love to know why. Amazon released a native C++ SDK for AWS if you're into pain. If you're using "OPAM" to install the OCaml AWS client... wow.

Re: C++ vs. OCaml: Ray tracer comparison (2005)

#4

Post by vvanders »

Kinda missing the point of C++ by using a linked-list.

If you're going to spend the time to implement an algorithm in C++ at least take the time to make it cache aware. Otherwise it's not really surprising when the performance is the same when you're doing the exact same thing.

Would be curious to see what the performance looks like with a tightly packed scene and static dispatch on a discrete number of primitives instead of using virtual functions.

Re: C++ vs. OCaml: Ray tracer comparison (2005)

#7

Post by thelucky41 »

The benefit of this comparison is not that the languages have nearly identical performance, but that OCaml can be briefer while accomplishing the same task, with 47% less lines of code.

Saying nothing about comparing LOC in an imperative/OO language to a functional one, does the brevity actually help a reader's understanding of the code at all? It seems to me that a lot of the comparisons call out descriptions of explicit actions in C++ where OCaml does the same action implicitly.

That seems like a language trade-off more than a feature.

Re: C++ vs. OCaml: Ray tracer comparison (2005)

#9

Post by duaneb »

chollida1 wrote: post #2

I work on a project that's a mix of F# and C++ and my code tends to break down very similarly to this. The actual algorithmic lines are very similar in size and readability but when it comes to defining your data structures, F#/OCaml clearly wins. The author of the website(Jon Harrop) is a very good writer and though his books are expensive I'd recommend them to anyone learning OCaml or F#. Specifically F#/OCaml for…

Yea, c/++ tends to have a memory oriented way of defining data structures. Sometimes this is great, but most of the time there is a lot of mental translation and work.

Re: C++ vs. OCaml: Ray tracer comparison (2005)

#10

Post by rwmj »

evanpw wrote: post #6

I'm surprised the performance of the two implementations is so close. Aren't floating-point numbers in OCaml usually boxed? Is the compiler smart enough to optimize away the boxes in this situation?

The floats in the structs are unboxed. Float arrays and all-float structs have a special representation[1] in the compiler so they are stored unboxed. I believe the developers of OCaml have expressed some regrets about this, but in this particular case it's likely to be a win.

Within functions, the OCaml compiler can assign floats to registers, so those would also be unboxed at least for the duration of the function.

[1] https://realworldocaml.org/v1/en/html/memory-representation-...

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