I really wanted to do pleats by creating a mesh in the right shape, rather than using normals....It took me close to two years off and on to figure out how to do that. The pleats are in fact folded just like real knife pleats (a good guide for making the real thing is https://www.carbonchic.com.au/2014/11/diy-knife-pleated-skirt/), or rather one pleat was folded and then repeated along a bezier curve made from an edge loop in the skirt helper (this introduced some distortions in size, but they're not horrible). The mesh was designed with quads, then transformed to tris (using "poke faces") before being exported as clothes, in order to deal with the non-planar faces necessarily created by the folding. The peculiar format of the UV map is also due to folding the mesh like real pleats: to get pixels to end up in the right places, the texture needs to be a long strip, just like a real pleated skirt is made from a long strip of fabric. Finally, note that if you want to do a cloth simulation on the skirt, you'll need to do some pinning, as the pleats aren't actually attached to the waistband. Credits: In the included material, the plaid texture comes from heartlessinu at DeviantArt (https://www.deviantart.com/heartlessinu/art/Red-plaid-215324313), while the zipper is from fuzzimo (http://www.fuzzimo.com/free-hi-res-zipper-textures-pictures/). UPDATE: Straightened some of the geometry in the waistband, and fixed a few problems that show up on specific models.
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