Hey all,
I was looking at some Driveclub videos and I still can’t believe how good the rain effect in that game looks. I know it’s been asked a lot of times if this effect can be recreated but nowhere is a good answer given, other than “use an animated texture, it might look alright”.
So, on reddit I found something interesting on this subject.
“Gonna guess a simple 2D particle sim with some low cost technique to get a metaball like effect then just build a normal map from that for a displacement shader.”
“Cheap 2D metaball = render particles to an empty texture with a big fuzzy particle image, then threshold.”
1: Simulate dynamic 2D particles
2: Make the particles react to the velocity and direction of the car
3: Make the particles interact with windscreen wipers
4: Use a blur and threshold to kinda create metaballs
5 (bonus): Let the moving particles leave a trail, so it looks like rain running down a windshield
Last but not least: make the ripples displace what you see behind your windshield and blur it a little bit, to make it look a bit more real.
I think all these things can be done relatively easily, except maybe for 3D wipers interaction with 2D particles. Problem is, I’m not a programmer. I can model 3D stuff, I can make textures, heck, I can even record and edit sounds. Also, I’m not asking you guys to solve this for me but rather for the community as a whole, just to make Unity that little bit better. Driveclub is the only game so far that has this kind of dynamic and realistic rain, so why not show that Unity can also pull it off?
Lets push it a bit further, because what if we as a community can pull this off? What’s the best way to show it off? I was thinking of using the vehicle example of Unity 5 just to keep it easy on that side, and create a track that looks a bit like what you see in that Driveclub video. It’s not really hard to make and that is something I would be able to do. Use the Lux Wetness shader from larsbertram1 to create realistic wet roads, combine it with SSR shader from Kode80 for realistic reflections and just create stunning visual demo with Unity.
I know you guys love creating amazing stuff with Unity, so why not try to recreate an effect that a lot of people really (REALLY) love? Who’s in? 
