Wrinkle Tension Shader v2
This setup uses the tension of surface to give the illusion of detailed fabric wrinkle deformation.
This is a Work in Progress.
The effect uses a custom modifier and shader node group to create the effect.
To copy this effect to your own model copy the "Tension Map" modifier onto your mesh (make sure Add Rest Position is enabled in the shape key tab) and then add the "Wrinkle Map" node group into
your shader.
The heightmap output can be put into a bump map node to create a usable normal map.
Things to note: