STL file color information

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My first recommendation is not to use that feature, but if it is a bit too late for me, as I did use it in the past. And old code needs some care from time to time.

STL files represent triangular 3D meshes, but do not support color in any shape or form. However, some non-standard way of adding color has been used by some companies in the past, and somehow, here we are, using color on STL files. 

If you do that, you may wonder what the actual colors are in your STL files, as this feature is quite sketchy for several reasons. So I asked DeepSeek to create me a single-page web app that could help me answer this question locally (without sending your 3D mesh to a web server). Not that the AI was completely willing initially, as it delivered only a shell with fake info, but a bit more persuasion produced a very usable result I am sharing with you here.

I decided to write this post instead of placing the AI blog entry (which I created and reviewed, though). 

I followed the AI advice and hosted the app on GitHub. 

But I can keep some of the IA-written closing comments:

Lessons Learned

  • Single File Applications: Modern browsers can handle surprisingly complex applications in a single HTML file
  • Client-Side Processing: Eliminates server costs and privacy concerns
  • Progressive Enhancement: The app works even if JavaScript is disabled (basic file input still functions)
  • Free Hosting: GitHub Pages is perfect for static web applications

Conclusion

This project demonstrates how powerful modern web technologies have become. With just HTML, CSS, and JavaScript, we created a specialized tool that would previously require desktop software or server infrastructure. The combination of client-side processing and free hosting makes sophisticated web applications accessible to everyone.

The STL Color Analyzer is now available for anyone to use, completely free, with no installation required - just a web browser!

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