Hello together!
I’ve been trying to create a desert landscape material. I want to simulate wind going over the sand with an animated texture, but the second lerp doesn’t work like I wished it would.
What I try to achieve:
Moving waves added onto the diffuse desert texture, but only on one side of the dunes.
What works:
The waves move as intended. However, instead of becoming masked/transparent at the other side of the dunes the color I put into the waves will reverse as you can see in the screenshot below.
Please note, that I set the scene to unlit and colored the wind green to be able to see it better. If I set the wind color to white the masked parts will turn black and after building light the results are the same. (Its still hard to see in the picture)
I tried multiplying, lerping the other way around, combining the two masks and then lerp between textures… everything I did turned out even worse.
Please, if someone could explain to me what I have missed / been doing wrong and help me find a solution I would be very grateful 
Best,
Franzi