This is my technique to create a poly roller coaster. It's not the fastest way to do it, considering that you can easily make a track by extruding a surface or a plane, along the curve of the track, then plug a black and white gradient into the transparency node to make the railway ties. You will get a flat track, so it's good for a long shot but not so great for a close-up.
With the technique in this tutorial, you will be able to control the overall look. I made a very basic one but feel free to add as much detail as you want.
PS: Pour les francophones qui ne comprennent pas l'anglais, n'hésitez pas à poser vos questions en commentaire.
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