Nyanneco Position Mask, released by Nyanko, is a Substance 3D Painter generator designed to easily create highlight masks, such as those for hair. It uses a Position map to determine spatial information and generates lines based on that data, placing shapes along them to produce highlights and similar effects.
Please note that it's strongly affected by UV layout, especially overlapping UVs, and its internal blur does not cross UV islands, which may result in visible seams. The generator can be used for commercial projects.
You can get it for free until July 5, and there is a tutorial video available, although it's in Japanese:
