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  ponyous
  This "screenshot -> refine loop" is a great strategy and I have built it into my 3D Modeling product as well[0], but had to disable it because it would often quadruple the costs and the product is already expensive.I am on standby to enable it though, just need a price to drop a bit more![0]: https://grandpacad.com
• s1mon
  I've been using Codex (GPT-5.4 extra high) to code custom FeatureScript in Onshape (3D mechanical CAD software). It's challenging to get it to do TDD that involves any visual reasoning. At the moment I've got tooling through Google Chrome Devtools MCP and Playwright to extract things and control the browser and I use some custom features which help with formatting and controlling debugging outputs (text and visual overlays). Mostly the text debugging outputs are very helpful to Codex. It will often add debugging payloads when we're focused on a particular issue. I do occasionally take screenshots and paste them into Codex and explain the issue that I'm seeing. It seems to understand a certain amount, especially if the issue can be seen in orthogonal views.
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  mungoman2
  Really good. I’ve struggled with the same thing.> Instead of expecting it to understand my requests, I almost always build tooling first to give us a shared language to discuss the project.This is probably the key. I’ve found this to be true in general. Building simple tools that the model can use help frame the problem in a very useful way.
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  sigmoid10
  >I still occasionally hand write code in NeoVim on the bits I care the most about (CSS, design and early architecture like API patterns)I find it amazing how people's opinions differ here. This is the first stuff I'd trust to Claude and co. because it is very much in-distribution for training data. Now if I had sensitive backend code or a framework/language/library that is pretty new or updated frequently, I'd be much more cautious about trusting LLMs or at least I would want to understand every bit of the code.
• Archit3ch
  I tried to generate python scripts for Blender with local models a while back and the results were pretty bad. I assume the frontier models of today would fare much better.
• neomantra
  My mind-blown moment was when I was doing work like this and Claude started positioning the camera itself to get better looks at areas it wanted to improve.
• bob1029
  I've been having pretty good success with unity as a 3d llm tool. In addition to the iso views I've included a perspective mode that can focus on a list of game object ids with a custom camera origin. The agent is required to send instructions along with the VLM request each time in order to condition how the view is interpreted. E.g.: "How does ambient occlusion look in A vs B?".The VLM is invoked as a nested operation within a tool call, not as part of the same user-level context. This provides the ability to analyze a very large number of images without blowing token budgets.I've observed that GPT5.4 can iteratively position the perspective camera and stop once it reaches subjectively interesting arrangements. I don't know how to quantify this, but it does seem to have some sense of world space.I think much of it comes down to conditioning the vision model to "see" correctly, and willingness to iterate many times.
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  ftcHn
  Great article. I've been trying to achieve something similar with a Revit. It's an old CAD application for Windows which means there's a few additional hurdles in exposing a cli interface that allows the LLM to drive it. However, once that is done, the loop of "write code, take a screenshot, repeat" works pretty well.
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  bambax
  Just yesterday I used Claude to great effect in FreeCAD to model a church tower. The tower has a square base and an octagonal top, but connecting the two by creating a loft using the GUI in FreeCAD results in a wrong and ugly abomination.Claude understood the problem and produced elegant Python code that worked perfectly the first time.So I continued and described the other features of the tower to Claude, who coded them.It's sometimes difficult to properly describe what you want in English, and Claude does a lot of thinking, and sometimes goes deep into a wrong direction of which it won't come out easily; but in the end the result is almost perfect.
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  8note
  gemini on the otherhand, isnt half bad.all i wanted was some opinions on if my bad idea would work, but it instead wrote me files for making my own sony earphones in 3ish parts.and when i sewed it together, it worked!that said, it did have full access to a mini CAD app, but i think it wrote all its own calculations inline
• rigorclaw
  The tooling-first approach resonates. I found the same thing building CLI wrappers for a side project -- once you give the model specific, constrained operations instead of open-ended prompts, the output quality jumps. It stops trying to be creative about how to do things and focuses on what to do. Almost like writing a good API: the constraints are the feature.
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  StephenHerlihyy
  Honestly understanding and applying 3d transformations should be a new LLM benchmark. Three.js, OpenSCAD, even Nano Banano prompts. The moment you add that extra dimension any semblance of ‘intelligence’ goes right out the window. Every model out there seems to spin themselves in circles trying to logic through it with no success.
• phendrenad2
  For people wondering before they click, this is about 3D CAD / 3D printing, not 3D animation.
• Sparkyte
  I thought about something similar with claude, I would like it to operate as an assistant for in something like unity engine.
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  bsjshshsb
  Got some excellent results vibe coding 3.js games with Claude. Maybe for printable things it is harder as precision is important though.
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  Razengan
  Claude is terrible. I've been using Codex for a few months and decided to give Opus a try and see how it is.After asking it to review a single file in a simple platformer game, it goes:> Coyote jump fires in the wrong direction (falling UP with inverted gravity) var fallVelocity: float = body.velocity.y * body.up_direction.y I'm like ok, suggest a fix> I owe you a correction: after re-analyzing the math more carefully, lines 217–223 are actually correct — my original review point was wrong. Let me walk through why.Oh boy. It's had several other gaffes like this, and the UI/UX is still crap (fonts don't get applied, it doesn't catch up with the updated working state after editing files etc.) Codex helped me save time but Claude is just wasting my time. Can I get a refund?
• ddactic
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• ddactic
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• stainlu
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• wonderfat
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