Show HN: DSLCad – a programming language and interpreter for building 3D models

by dschroer • 3 years ago

198 92 3 years ago

Hey HN. Over the last half a year I have been working on a 3D CAD programming language called DSLCAD. Today I am here to show my first release!

It is heavily inspired by OpenSCAD which got me hooked on the idea of a CAD programming language and what it can do.

Please let me know what you think. Ill be in the thread to answer any questions you may have.

h2odragon2• 3 years ago

I think your front page needs a lot more "what it does" and "what it doesn't (yet)". above that it needs a "why this is not SCAD."

I suspect most people bouncing off openSCAD are upset by the "programming" language, so I hope yours is simpler and has less "functional" annoyances.

Having the first part of your landing page explain how your project doesn't require forcing one's mind through the eye of those needles like SCAD does would be a great step to get people interested in trying to do things with it.

dschroer16• 3 years ago

Thanks for the suggestion. Ill see what I can add to make it clear.

cjbgkagh• 3 years ago

IIRC I also think the OpenSCAD language has its issues but I wouldn’t call them “functional” annoyances. The composition in OpenSCAD is really weird in a way that I haven’t seen in any other language. The unnamed arguments you must access by position. The inability to create new types and thus the limitations of the kind of types you can work with. The workarounds to these limitations are much clunkier than having such things supported first class.

I guess it’s trying to be accessible to non programmers by maintaining a ‘simple’ interface. But as a programmer I find the language really lacking. In theory a restricted interface could improve performance but there are so many low hanging fruits that OpenSCAD doesn’t do that it’s hard to imagine that performance was a priority and the workarounds end up costing much more in performance.

Brian_K_White5• 3 years ago

A functional aspect of openscad is you can never modify a variable.

You have to write some pretty obtuse contortions to do some pretty common and useful things, just because of that.

croes• 3 years ago

The link to the documentation page gives 404

dschroer16• 3 years ago

Should be fixed now. CI issue

roel_v3• 3 years ago

This looks awesome. If the 'fillet' works, that'd be enough for me to switch from OpenSCAD. Although to be honest, having a utility library like BOSL would be necessary too, or at least some way to make threads.

I'm going to download but another thing I would need to switch away from OpenSCAD - the ability to use an external editor, where the 3d model reloads correctly every time I save the program. Maybe your already has it, I'm going to check it out :)

dschroer16• 3 years ago

It is designed for use with an external editor. It watches the files and hot reloads when you save changes. I didn't want to do a sub par job building my own text editor.

I cant wait to hear about how it turns out for you.

MrLeap2• 3 years ago

I've made my own fully 3d lovecraftian text editor, I'd like to give this a try and see if I can make a 3d object for my text editor, with my text editor.

Does it contain facilities for export into non-parametric mesh formats? (.obj / .fbx / collada..) np if not.

WillAdams3• 3 years ago

While I understand not wanting to include a sub par job --- just including a basic text editing facility (whatever is included as the native text object in your programming toolkit) would lower the bar for new users, and facilitate folks doing quick/simple/one-off projects.

roel_v3• 3 years ago

Oof I'm back already, this is quite rough.

No editor included I see, that tripped me up for a second but it's IMO better than wasting your time on including one, once I got that it was fine.

I tried to enter the smallest program I could think of:

    cube(x=10, y=10, z=10);

but I couldn't get that to show anything. I can't resize the console it seems? So I'm not sure if there's an error on there. Either way, I'm not sure how I would go about finding out why I'm not seeing anything.

3d navigation seems wonky but maybe that's because there is no object yet? Sketchup has the same, it's no big deal, but I won't know until I can get something to render.

Some quick wins:

- draw axes in different colors and put a label on them - show scale markers on axes - add a minimal sample program, or some way to select a 'template' when doing 'new' that will provide a few samples - one minimal sample with a cube and a cylinder, one slightly more developed like the table in your screenshot, one that shows off each keyword/object. Maybe split across one for 2d, one for 3d. Or more as the library of functionality grows.

More work:

- Add a 3d navigation marker/tool like Blender has, that'll show where I'm looking at, and has 'zoom to all' function

All of these would have helped in terms of 'getting started'.

Apart from that - I'd first need to be able to at least render something to be able to say something useful :)

dschroer16• 3 years ago

Interesting. I just tried your example and it worked on my end.

Have you tried rendering any of the examples in the repo? I know its not ideal but just to see what is going on. Please add an issue on the repo so I can try to fix the issue you are experiencing.

virtualritz3• 3 years ago

No editor included I see, that tripped me up for a second but it's IMO better than wasting your time on including one [...]

It's using egui for the UI so adding an editor (w. syntax highlighting for the custom language) should be very easy[1].

[1] https://github.com/emilk/egui/blob/530e9f667c0969b09edb68f77...

mkeeter• 3 years ago

Can you say a little more about the geometry kernel? Is it NURBS-based, triangles, f-reps, etc?

IIRC, OpenSCAD uses CGAL and is all triangles under the hood; other tools use OpenCascade for NURBS modeling, or weirder DIY kernels.

TkTech2• 3 years ago

It's using open cascade.

digdugdirk• 3 years ago

Very cool! What modeling kernel does it use?

Out of curiosity - are you a mechanical engineer? I'd be curious to know what your history is with different CAD programs, and what effect that had on the design/use decisions you made with DSLCAD.

TkTech2• 3 years ago

It's using open cascade.

dschroer16• 3 years ago

Its using open cascade.

I am not a mechanical engineer. I am a software developer however I have worked closely with engineers and have some experience with CAD applications.

Really most of my decisions come from working on larger projects in OpenSCAD as well as my contributions to the OpenSCAD project (WASM port).

junon2• 3 years ago

Your LICENSE file is misspelled, by the way.

dschroer16• 3 years ago

Fixed. Thank you :)

OJFord2• 3 years ago

Your LICENCE comment is misspelt, imo. ;)

mvnuweucxqokii• 3 years ago

Years ago I came across this talk about a guy who built a Clojure wrapper around OpenSCAD in order to design his own keyboard. Potentially relevant:

https://youtu.be/uk3A41U0iO4

Cieric• 3 years ago

Loved the idea of the Dactyl Manuform when I first saw it, however in the act of trying to customize it to exactly what I needed/wanted I found the whole process convoluted and annoying. I understand the idea behind it now and might try and set my environment up to match his (since I didn't know he had a video on it.) But either way I can't see this as being a good solution to the problem.

zellyn• 3 years ago

It might be nice to be able to install it with homebrew on MacOS.

btw, I know it's not open source, but you might be interested in KittyCAD: I believe they're looking for software developers with CAD experience. And you could do worse than work with Jessie Frazelle!

dschroer16• 3 years ago

I am not very familiar with the homebrew packaging process. I would be happy if someone wants to help set that up.

Ill take a look into KittyCAD. Seems like a cool idea and is worth digging further into.

nicoty• 3 years ago

Oh interesting. I've recently tried learning JSCAD as I'm trying to model my freeline skates [(current progress here)](https://gist.github.com/nothingnesses/dc1171c2e20f7a6d9a1cb9...). I like it as I'm already familiar with JS (one reason I opted for it instead of OpenSCAD) and I don't have to compile/install anything but my browser. However, I'm running into a limitation with it as it doesn't have a native function that allows me to bend models, so I'm currently trying to write one.

Is it possible to bend models easily in DSLCAD? What would you say are some reasons why someone might use DSLCAD instead of JSCAD?

dschroer16• 3 years ago

From my understanding JSCAD is aiming to be 1:1 compatible with OpenSCAD. So both strengths and limitations will come with that.

DSLCAD is a new take on the idea. Right now it doesn't support bending, however from my personal opinion, DSLCAD is simpler to develop for and should make it an easier platform to add bending support to.

Feel free to add an issue asking for bending and we can hash out how to make it work. Getting the API down is often as hard or harder then implementing the solution.

gfodor2• 3 years ago

If you like the idea of a "markdown for 3D models", you should definitely check out Smooth Voxels: https://svox.glitch.me/

I have a fork of it that is faster and also command line tools to make working with these kinds of objects UNIXy. https://github.com/webspace-sdk/smoothvoxels

pvillano2• 3 years ago

Could I use this to make a very high genus watertight mesh for 3d printing? I want to make an irregular lattice for SLA 3D printing

gfodor2• 3 years ago

Not sure - this isn’t really a CAD library, it’s more for computer graphics.

levpopov• 3 years ago

Very cool, and excited to see more "Geometry as Code" tools getting built. In addition to comparing to OpenSCAD it'd also be awesome to see a comparison to CadQuery.

AlbertoGP• 3 years ago

The inertial model rotation is a pleasure to use, I’ve done the same in some of my programs and while it feels a bit strange at first it does make it easier for me to perceive the shape as it moves.

empressplay• 3 years ago

Great stuff! If you're interested in something similar with a simpler language (Logo) and relative model construction (using the turtle) check out turtleSpaces: https://turtlespaces.org/2021/09/08/how-to-create-and-3d-pri... You can export STL files and 3D print them. We'll be adding a multi-color export method soon

mk_stjames7• 3 years ago

I wish there was a way to combine the power of an imperative language driven model generating language like this (that generates breps, NOT meshes like openscad) but with the initial modeling using a GUI like a standard CAD tool. The reason being, it is much, much faster to draw complex parts using traditional methods versus trying to 'program' them. Writing code is fine for basic shapes, but go and try an 'code' a complex ribbed casting with bezier-definied swept surfaces.

I'd love to see a way to generate models with normal tools but, in the background, be able to access a code file that could then be embedded in an external script, headlessly. This way, say I have a part where 3 parameters change- I could take the code for that part, nest it in 3 for-loops, and iterate thru all the combinations of dimensions, procedurally generating the models (and potentially exporting them to a permanent format). FreeCAD allows actions to be scripted with Python but again, the actions have to be done in the language first- there is no 'going backward' from a part done in the GUI to Python (from what I can tell).

This is what parmetric programs like NX, Catia, Solidworks have the ability to do via "design tables" or other internal tools. But even those tools don't have an easily portable 'language' that the models are portable in, and the kernels aren't something that you can get in and poke around with (or interface with, say, Python, which is my dream).

Just food for thought for the author of this.

speps• 3 years ago

See Houdini: https://www.sidefx.com/

As a programmer, it's my favourite tool to make meshes. It's become a game studio standard over the last decade.

mk_stjames7• 3 years ago

Meshes are not CAD data. Engineering applications need math surfaces, and thus use Boundary Representation (brep) based models, not triangle meshes.

This is the main difference between video games & vfx tols and engineering CAD tools and the reason why there is so little crossover in the software development of those tools.

The author's tool here uses OpenCascade which is a true solid modeling brep kernel, hence my comments.

throw_m239339• 3 years ago

Houdini, as a mesh based modeler, also called artistic modeler, is not appropriate for industrial design, because of the way it handles topology like every other mesh modelers.

This is a very different use case. CA industrial D software are actually aware of how machine tools work, that's why their tools and API are named based on real machine tools and have the exact same constraints as physical machine tools. Houdini has no such constraints nor awareness about manufacturing trade, anything goes including non-manifold geometries in topologies.

eternauta3k• 3 years ago

I've done that with the excellent Salomé[1]. Model and mesh something manually, export my actions to a python script, clean it up and refactor it.

https://www.salome-platform.org/

mk_stjames7• 3 years ago

Wow, yep a quick look and this is exactly what I am talking about. I was aware of the Salome project as the FE pre and post tools for code_aster and I'd even used the geometry and meshing tools before years ago, but had no idea they had a much fuller fledged CAD tool in this 'Shaper' module.

Honestly it's kinda buried in the fact that Salome as a whole has so many domains. I feel like more people would use this if it was promoted standalone. In some ways it looks similar yet more useable than FreeCAD.

trehans2• 3 years ago

This is great! I've been looking for something like this for a while. My only question is: does this do constraint-based modeling like other CAD software or do you have to specify individual parameter values?

dschroer16• 3 years ago

Hey. I'm glad that this is what you are looking for. At the moment there isn't constraint based modeling. However given that you have a programming language at your disposal you can model your constraints yourself.

trehans2• 3 years ago

Thanks for the reply!

Would you accept a PR for first-class support for specifying constraints between variables (and object measurements) as part of the language or would that be divergent with the goals of the language? I find it to be an important part of SolidWorks etc. because often times I'm trying to build something where I know one of the dimensions is constrained a certain way but that's not how I'd parameterize the object. And I don't want to be doing math for e.g. calculating the diagonal over and over again as part of calculating parameter values or modeling constraints, I like that in Solidworks that's part of the package. I believe this issue is important to other mechanical engineers as well.

However I do want to say, great work, I think a programming language is a great step forward for CAD regardless, and this project seems to be pretty well done!

loa_in_• 3 years ago

See also open source Pov-RAY. Not my software. It has full featured boolean volumes, and could be called text based Blender.

http://www.povray.org/ https://github.com/cyborg5/pov2mesh

dTal4• 3 years ago

It couldn't; POV-Ray outputs images, not meshes or CAD models. It is purely a graphics tool.

naasking2• 3 years ago

The project page says it outputs a triangle mesh. POV-Ray would have to have a notion of volumes and surfaces in order to calculate shadows and reflections.

dTal4• 3 years ago

This is great, we need more of this sort of thing. Huge kudos for making it and documenting it. I will definitely be taking it for a spin.

1) Do you plan to add 'loft'? Without it, or some other type of morphing extrude, one is severely limited in the types of shapes it is possible to create.

2) I hope you don't mind me asking, what is the psychedelic-looking image I can see a sliver of in the screenshot? It looks like a rocking desktop background.

By the way, if you're not already aware of it, you may also be interested in looking at ZenCad for inspiration. It attempts to fill a similar niche (OpenSCAD-ish modeling + OpenCascade), except it uses Python.

dschroer16• 3 years ago

Thanks for checking it out. I am glad you like it.

1. Now that you have asked for it, I certainly plan on adding `loft`. Thank you for the suggestion. Looking quickly it looks quite reasonable to implement. I would expect to add it in the near future.

2. It is a digital art coloring book image that I filled in and used as a background.

virtualritz3• 3 years ago

Here is another programmable CAD project, Fornjot[1], also in Rust. Fornjot, too, is being actively developed.

Unfortunately it uses Rust for model description (compile times/learning curve).

That said, one could probably easily put a layer of scipting lang in-between. E.g. Rhai[2] or Lua or whatever.

And I guess if their tech is solid enough, someone will do that eventually and open a PR or fork the project. They do not use an existing geomtry kernel but do everything from scratch which makes this a very interesting endeavour.

There also seems to be a goal overlap between Fornjot and DieselCAD

[1] https://github.com/hannobraun/Fornjot

[2] https://rhai.rs/

hannobraun2• 3 years ago

Hey, author of Fornjot here.

Rust was chosen as a modeling language for two reasons:

1. Since the whole project is written in Rust, it was the most straight-forward choice. No dealing with bindings to another language or a scripting language runtime for the time being. 2. To provide an interesting alternative. I suspect that there can be a nice niche for Rust, creating infrastructure for writing models (e.g. libraries for generating screw threads, that kind of stuff).

I don't think that Rust is a great language for defining CAD models. Long-term, I suspect that the preferred choice for Fornjot will be something else. But for the time being, this decision allows me to focus on the CAD kernel.

There also seems to be a goal overlap between Fornjot and DieselCAD

Do you have a link for DieselCAD? Searching on Google only got me car results.

siemensikkema• 3 years ago

This reminds me of https://github.com/nicklockwood/ShapeScript although that is limited to Apple platforms.

zem• 3 years ago

quick comment - if you have to note in the readme that it's pronounced "diesel cad" you should just rename it "dieselcad" and be done with that stumbling block.

dschroer16• 3 years ago

You are probably right. The Linux hacker in me still kind of prefers having a bit of style to names. Maybe over time this will change.

mk_stjames7• 3 years ago

If you haven't seen it you may want to check out https://github.com/zalo/CascadeStudio

From what I see, it is exposing the OpenCascade base commands directly, versus your completely new DSL, but you might be interested in a way to implement your DSL on top of such an interface such as this which takes out a lot of the extra work of having a rendering interface, exports, etc, maybe.

rcarmo• 3 years ago

Chamfer and fillet are awesome, but the pipe… mixed feelings, especially since it uses a dash. Either a normal pipe or an Ocaml-like |> would feel more natural.

dschroer16• 3 years ago

The goal of pipe is to allow the code to read top to bottom. I always found it hard to explain the way an OpenSCAD program reads upwards when nesting operations.

As for the syntax there are certainly a lot of ways it could feel. JS devs would likely be familiar with =>, F# and Ocaml |>, Java ->. In the end I just picked one that felt natural to type for myself. From my experience if you write in enough languages you develop the ability to switch as needed.

pvillano2• 3 years ago

This might be the right thread to ask for help with a 3d problem I've been working on for a year or so.

I have a resin 3D printer, and I want to make handles for it. Specifically, ultra lightweight handles using an irregular lattice.

OpenSCAD chokes on trying to union 100s of cylinders. Real tools cost $1,000s. Right now it looks like I'll have to write something to do the union in voxel space

pvg• 3 years ago

It's not really because Show HN is specifically for people showcasing their work and getting feedback. But there are lots of other kinds of threads where it might fit up to an including posting an Ask HN of your own.

noncoml• 3 years ago

1. FreeCAD. I am not 100% sure what you are trying to do, but FreeCAD most probably con do it. And the forum is there to help you if needed.

2. 3DExperience Solidworks for Makers. It's something like $100/year.

OJFord2• 3 years ago

For work or hobby? Fusion360 doesn't cost a penny for the latter. (I'd love to use code or FreeCAD or ideally FreeCAD stored as sane human readable code, but none of the options are quite what I imagine.)

elromulous• 3 years ago

I'll have to check this out. Really great to see more of "cad as code". My current favorite is cadquery. It's pretty neat in that it simply is python.

https://github.com/CadQuery/cadquery

WillAdams3• 3 years ago

Would writing out text files be an option?

I've been trying to do this from OpenSCAD (now using RapCAD) and while I sort of have it working:

https://github.com/WillAdams/gcodepreview

I'm not so far along that I wouldn't try something else.

dschroer16• 3 years ago

You have a super interesting use case. Can you reach out on the github issues so that we can track it? From what I can tell you are trying to generate GCode directly from the software is that the case?

WillAdams3• 3 years ago

Yes, that's it exactly --- basically trying to avoid the need for additional CAM software and provide complete and total control over machine movement.

qualudeheart• 3 years ago

This is very cool. Do you use Github Sponsors so I can tip you?

Show HN: DSLCad – a programming language and interpreter for building 3D models

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