Add mesh thumbnails in modal

[AnuKritiW]

Currently, the mesh preset modal displays a simple list of .obj filenames. It would be a nice quality-of-life enhancement to show a visual preview (thumbnail) for each mesh, helping users quickly recognize the shape or structure of a preset.

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Problem

macOS Finder for example shows thumbnails for .obj files.
Similarly, I would like to generate a thumbnail for the modal.

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Possible Solutions

1. Pre-rendered thumbnails

   • Use a tool like Blender, Three.js, or WebGL/WebGPU to render the .obj files and export thumbnails as PNG images.
   • Store them alongside the mesh files (e.g. /public/mesh/thumbs/sphere.png)
   • Match image to .obj filename in the modal UI.

   Pros: Fast rendering, no runtime performance cost
   Cons: Requires manual or scripted generation step

Note: Optional Automation
Consider writing a small CLI or script that:

• Loads .obj files
• Renders them with a basic camera and lighting setup
• Saves PNG thumbnails to /public/mesh/thumbs

2. Live WebGL/WebGPU rendering

   • Dynamically render the .obj in a <canvas> thumbnail using Three.js or WebGPU when the modal opens.
   • Could support rotation or basic shading.

   Pros: Dynamic and always up-to-date
   Cons: Adds runtime complexity and GPU load

3. Fallback: Filename-only (current behavior)

   • Keep using a list of file names with download/view icons only.
   • Acceptable default for MVP.