Hey,
I’m trying to find a solution to quite a specific problem in the material editor. Basically, I work with realtime hair and I am trying to find a way to invert the flow maps for specific cards that are ‘backfacing’ or flipped from when the asset was created.
The solution I’m looking at implementing is this, on the asset I offset my backfacing cards to the second UDIM or +1 on the U axis. Then in engine I sample this and invert the channel that governs the direction of the flow map texture (this drives the anisotropic reflection)
The point here is to make sure the anisotropic reflection follows the right direction. As we flip the cards when creating the asset these cards need to have their green channel flipped.
Here is my current graph
My question is how would you combine these together afterward?
Currently an add doesn’t work as it changes the values for the first UV tile as well. If you look at the tips of the hair here even tho the direction is flipped the colour is no different
I was thinking a linear interpolate function would help but I’m not quite sure how I could mask the UV tiles from one another