Comment by bdcravens

3 days ago

Text being a challenge is a symptom of the bigger problem: most people have a hard time thinking spatially, and so struggle to communicate their ideas (and that's before you add on modeling vocabulary like "extrude", "chamfer", etc)

LLMs struggle because I think there's a lot of work to be done with translating colloquial speech. For example, someone might describe a creating a tube is fairly ambiguous language, even though they can see it in their head: "Draw a circle and go up 100mm, 5mm thick" as opposed to "Place a circle on the XY plane, offset the circle by 5mm, and extrude 100mm in the z-plane"

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bdcravens

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numpad0  3 days ago

I don't get the text obsession beyond LLMs being immensely useful that you might as well use LLM for <insert tasks here>. I believe that some things live in text, some in variable size n-dimensional array, or in fixed set of parameters, and so on - I mean, our brains don't run on text alone.

  • guhidalg  3 days ago

    But our brains do map high-dimensionality input to dimensions low enough to be describable with text.

    You can represent a dog as a specific multi-dimensional array (raster image), but the word dog represents many kinds of images.

    • numpad0  3 days ago

      Yeah, so, that's a lossy/ambiguous process. That represent_in_text(raster_image) -> "dog" don't contain a meaningful amount of the original data. The idea of LLM aided CAD sounds to me like, a sufficiently long hash should contain data it represents. That doesn't make a lot of sense to me.

nitwit005  3 days ago

But, you need the ambiguity, or the AI isn't really a help. If you know the exact coordinates and dimensions of everything, you've already got an answer.

  • gmueckl  3 days ago

    Not necessarily. Sometimes, the desired final shape is clear, but the path there isn't when using typical parametric modeling steps with the desire to get a clean geometry.

arjie  3 days ago

When I use Claude to model I actually just speak to it in common English and it translates the concepts. For example, I might say something like this:

    I'm building a mount for our baby monitor that I can attach to the side of the changing table. The pins are x mm in diameter and are y mm apart. [Image #1] of the mounting pins. So what needs to happen is that the pin head has to be large, and the body of the pin needs to be narrow. Also, add a little bit of a flare to the bottom and top so they don't just knocked off the rest of the mount.

And then I'll iterate.

    We need a bit of slop in the measurements there because it's too tight.

And so on. I'll do little bits that I want and see if they look right before asking the LLM to union it to the main structure. It knows how to use OpenSCAD to generate preview PNGs and inspect it.

Amusingly, I did this just a couple of weeks ago and that's how I learned what a chamfer is: a flat angled transition. The adjustment I needed to make to my pins where they are flared (but at a constant angle) is a chamfer. Claude told me this as it edited the OpenSCAD file. And I can just ask it in-line for advice and so on.