Rain

[glorybound]

I need to create a scene with rain, rain running down a roof, and over/into gutters. Can someone point me in the right direction on how to do this?

[Svetlin.Nikolov]

Hey, check this tutorial, it should give you ideas about techniques. In order to make the liquid slide better and not stick strictly to the roof, you could reduce the Sticky Liquid option in the Dynamics rollout.

[Svetlin.Nikolov]

Depending on how close the camera show should the drops, using particles as emitters of the droplets, or the particles being the droplets until they reach the bottom surface, could also be an option:

[glorybound]

Hey, check this tutorial, it should give you ideas about techniques. In order to make the liquid slide better and not stick strictly to the roof, you could reduce the Sticky Liquid option in the Dynamics rollout.

This is awesome! Thank you.

[Joelaff]

Svetlin and the Phoenix team are the bomb! These folks will not steer you wrong, and will do everything they can to help you.

My best interactions with Chaos are always with the Phoenixers! (Nothing against the rest of the Chaos crew, mind you, but these people really go above and beyond.)

[Svetlin.Nikolov]

Wow, I hope we are doing it well, thank you! <3

[glorybound]

I am going nowhere, and fast! Doesn't look like droplets of rain, nor can I get it to run down the roof and over the gutters. Here is where three hours of play got me.

[Svetlin.Nikolov]

Ah, but what settings did you use and in general how did you set the rain up?

[glorybound]

I tried to follow your videos. I don't have Tyflow, so I used a PF source.

[glorybound]

Don't laugh

[M.Max]

Are you going to render it in animation? if not then you can create 2 sims like following :
1- the rain dropping from the sky and running over the roof .
2- a stream of water running through the gutters ( just like simulating river )

I had to do this for a project recently and that give my much better control over the simulation where I can reduce /increase one sim without affecting the other .

[glorybound]

One will be an animation, but the others (six in total) will be stills. I thought about your idea, so if I have to, I will try that.

[georgi.zhekov]

Hey Bobby,

Just checked your scene and I have a few suggestions.

Your liquid source is emitting way too much liquid and this prevents the water to look like rain and more like a huge liquid splash. In my test I lowered the liquid source Outgoing velocity to 0.1

Then in the dynamics settings you had sticky liquid set to 1, which caused the liquid to stick directly to the roof without while in reality it should slide over it. You can try something like 0.2 or 0.5 for the sticky liquid and adjust to taste.

When you have fast moving liquid - it's better to use more steps per frame in order to compensate for the fast movement (this will slow the simulation so be careful when you raise them). In the case of your scene I used 4 instead of 2.

In the scene you have a huge simulator grid that covers the whole house while the camera sees only a fraction of that. Since your camera is super close - you will need a huge grid resolution to get proper detail. Maybe you can use 2 simulators - 1 with higher grid resolution that will be used for the closeup and another one with lower grid res for the whole house (in case you wish to make a shot with the whole house). I also disabled the initial Fill for the simulator in order to speedup the simulation since the focus is on the rain.

Also when doing simulations it's best to exclude or hide the geometry objects that don't need to interact with the liquid, otherwise the sim will slow down unnecessary). You can use the Scene Interaction rollout and exclude objects from the sim or just hide them.

This is what I got and my settings.

The idea M.Max suggested about the two simulations is great - so give it a shot.

Hope this helps!

[glorybound]

Thank you! it would be nice to have an easy rain setup, but I guess I need to learn it. I'll try again.

[georgi.zhekov]

Oh yes, ideally it should be a preset or/and example scene. Adding it in the to do list.

Meanwhile we also have this shower example scene which kinda reminds of rain - https://docs.chaos.com/display/PHX4M...eScenes-Shower