I have decided to write complete Alien vs Predator shaders. Because of it, there are Xenomorph Vision and Predator Vision.
Most games just increase brightness and use green filter (in post-processing). It is easy to implement (because we do no change in shaders) but the effect is not what we want (not real enough).
To do
realNight Vision, we will need to have alternative shader for all existing shaders (required only for 3D shaders but I recommend you to also modify your GUI for better effect).
Our shader will work as normal lighting shader but we will use grayscale texture and (also grayscale) light with greater impact on result. Then we use the grayscale for green part of color (y of vector) leaving other parts (red + blue) at zero.