World Scale UV Tiling

I have a material library in Unreal that uses real-world values to calculate how much they should tile.

I needed the ability to apply any material to any mesh in Unreal, including custom unwrapped ones, and have the materials be at the same scale. This script solves that issue.

If I wanted to solve this manually:

• For non-custom unwrapped meshes I can assign a UVW_Map in 3dsmax and set the size to ‘1m x 1m x 1m’ and it will look correct in Unreal with those materials applied. 
• For a mesh that has custom unwrapped UVs, I don’t have this option, I need a way to scale them to any arbitrary size (in my case 1m x 1m) so my Unreal materials tile correctly on them.

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