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Comment by h2odragon | Hacker News Reader

I love OpenSCAD for everything but the language, which is .. so bad that the rant stays corked.

Perhaps the 3MF https://github.com/3MFConsortium output format could be useful too?

Edit: ah, i didn't see any dates; but I do see a "Google+ community" link ... Perhaps there's more to be done to make this a viable alternative.

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Looks like the last commit was in April of 2019.

EDIT: There's a giant V2 branch with newer updates and updated links to their new community. I am not sure they realize how dead the project looks with no commits to master since 2019 and Google+ links on their homepage and readme.

Does V2 support STEP output? As a semi-professional (i.e., an engineer, but not a mechanical engineer, using this for work purposes that aren't 3D printing), anything that does not support STEP is simply useless to me.

Curious, what do you dislike about it?

I used it for a project recently and found it to be really nice and expressive. I love that it's got a functional feel but you can do loops and compose modules in a really powerful way.

I used OpenScad a few years ago and was also initially horrified by the language until someone pointed to me the "nightly build" versions which supported the functional feel and compositions that I think you are describing. Those made a world of difference for me. I wonder if the parent is referring to a really old version (many Linux distributions still ship those). Just a guess.

Yes. I built a project using the 2015 release. ugh.

https://github.com/h2odragon/MarksEnclosureHelper

Ah that might explain it. I picked it up recently from scratch using the nightly build (via snap) so I'm not aware of the history of the language.

The old version language was bad to the extent that after playing with the tool for a few hours my thought was "why did you cripple such a good idea with such a bad language"??? I seriously considered digging out the Dragon Book to write a better language front end to it.

For me, the syntax is ok, however it doesn't always do what you expect. For example:

    if (some_condition) {
        x = 2;
    }

x doesn't get set to 2. Or even better, this:

    x = 2;
    echo("x = ", x);
    x = 5;

This prints out that x = 5.

It is not an imperative language even though it is dressed up like one. You are describing a data structure, not a sequence of operations.

It should technically throw an error before compiling. You're thinking about it as an imperative language, when it aspires to be declarative.

Personally I think that's a bug, not a feature. If the language aspires to be declarative, but features imperative constructs, it should have a syntax that reflects the distinction.

I work with these kinds of things a lot, having that clear divide between declarative and imperative operations on whatever being expressed isn't only easier to learn and read, it's far more expressive and powerful for complex systems.

You misinterpret--or rather, I wasn't clear. While I say it aspires, I'm not saying it's a good choice.

I'm just saying its odd behavior makes a lot more sense once you know it's meant to be declarative, and you can make a lot more headway when working with it.

Not OP, but :

- you can't store objects in variables, so code looks convoluted with deep nesting as you need to apply multiple transforms to objects

- there are no real variables, more like constants that take the value of the last assignment, so you can't do basic stuff like x = min(x, 5)

- you can't access object attributes (size, etc.) so it's not possible to generate features that depend on another object. You always need to have lots of parameters in scope. A simple use case would be to punch 4 holes in the corners of a box cover.

- string functions are very limited, there is only str() to convert a value to string but with no control on the formatting, there is no printf-equivalent

I'm able to do some of these things. Someone else said that perhaps the nightly build is different?

``` module thing(x) { cylinder(r=x,h=10); }

translate([10,0,0]) thing(5); x = min(4,2) + 1; translate([-10,0,0]) thing(x); ```

works for me.

Your third and fourth points are good ones. I think the first two points are mitigated by using functions and modules correctly.

The syntax looks like C but it's not, and causes bugs, e.g. in this loop:

  i =0;
  for (j = [1:5]){
      echo(i);
      i=i+1;
  }

keeps printing "1" instead of 0 to 4

I actually really like the OpenSCAD language; I've even started to prefer OpenSCAD to Fusion360 for sketching ideas in recent years.

It is very easy to import modules for operations like threaded holes or gear teeth, and it feels very familiar if you are coming from a graphical CAD tool like Inventor or SolidWorks because it follows the same process of generating parts from a nested series of elementary operations. I've never felt frustrated trying to write parts, but to be fair, I also don't use it for serious manufacturing.

There is an attempt to be able to write it in clojure.

https://github.com/farrellm/scad-clj

Haven't tried it but enjoyed this talk (about 3d printing ergonomic keyboards using the above): https://www.youtube.com/watch?v=uk3A41U0iO4

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