Ocean storm

[crimea]

Hi.

I need to make a storm in the middle of the ocean with semi-sub oilrigs that the waves crash against and create splash, much like this thread: https://forums.chaosgroup.com/forum/...hole-in-render

So far it's not going great, see my current result and setup attached, or download full quality and longer movie below:
https://we.tl/t-8YmBrgNqUJ

Does anyone have any tips for a good setup? Doesn't need to be fully realistic, just something that doesn't have loads of bad-looking issues like mine does, and looks somewhat like a storm like these: https://www.youtube.com/watch?v=YnJzJ9lBm20 https://www.youtube.com/watch?v=D2dv57CpT-s

Also I will be needing to blend this with a full ocean, but if I enable the phoenixfd oceantex and use ocean mesh, the displacement goes haywire and becomes way too strong on the simulation, and the edges are not blending at all. Also, it looks like the foam is moving the opposite way of the water.

This is tricky to get looking good Any help or alternative methods are very welcome.

[georgi.zhekov]

Hey,

Looks like you're using quite old version of Phoenix. Make sure to get the latest 3.12 build as we did quite a lot of fixes and improvements.

Then - check your scene scale - currently you're using generic units and it's not really obvious what your scale is.

Probably you need more resolution as well.

[crimea]

Hi Georgi and thank you for replying. Unfortunately we can't upgrade without spending some time making sure that things will work, since we have had huge issues with newer versions previously, forcing us to downgrade after half a year. The system units scale is meters, and all the objects are realistic scale. Can't afford much higher resolution unfortunately.

[Svetlin.Nikolov]

What kind of issues did you have? If you describe them, we will be able to tell you whether they are already fixed, if they were on our side. Or, we will be able to start working on them, if we already are not.

Cheers!

[Svetlin.Nikolov]

Regarding your current setup - as Georgi said, please switch the units to something other than generic units, so we can make sense of the scene scale.

You can compare your ocean texture and scale settings to the beach waves example scene here: https://docs.chaosgroup.com/display/...nes-Beachwaves

There was also a thread here in the forums with an example scene attached for a stormy ocean, with plain force blowing mist into the air form the wave crests, which should be closer to what you are looking for as an effect.

Stitching this kind of setup using wave force with an infinite ocean will not be seamless. You need to have a separate ocean texture driving the wave force, and another once for the ocean displacement, or the displacement will double the wave sizes inside the simulator. It would still be difficult to hide the connection between the stormy simulator and the infinite ocean without using certain camera angles or post though.

Cheers!

[crimea]

Hi Svetlin. The issues I'm talking of are those that I made a thread regarding maybe 1 year ago, where infinite ocean created lots of black noise in the horizon, needed 3-4 times as much memory, and took longer to build at the start of rendering. You did fix this issue mostly I believe, but in the tests I did it did seem to still consume a lot of memory compared to this older version, as well as needing more time to build. That's one issue, another issue we got when we tried rendering older simulations was blending the simulator box with the infinite ocean. See here for example, notice both the horizon noise as well as the lines around where the sim box presumably is. This latter issue I was having big problems with a few weeks ago when we had to use max 2017 where we have newer vray and newer phoenix fd - what ever I tried to do, I could not blend the sim box with the rest of the ocean at low angles. Didn't mean to bring those up in here, and again.

Regarding this sim's scale, you mean scale of the objects? Look at the reference videos I posted for that. The second one is best. And again, the scene itself is in meters, and everything is in realistic scale according to the system units (meters). So, all the parameters are meters.

Thanks for the tips of that other stormy ocean scene, will look into it.

The current plan regarding stitching sim sea and infinite sea together is simulating a big version in low rez that I will mask in in post, but I have no idea if it will look good, might require a lot of work to blend it in fairly OK. Was hoping someone had a better suggestion, or just tips of how to execute this plan successfully, as I've never done exactly this before.

How can I have a separate ocean tex for the sim and the infinite ocean?

By the way maybe you should remove this from the docs then "WaveForce is used to create seamless interactive ocean simulations due to similarities between the simulated waves and the waves of the ocean extension.", gave me false hopes..

Thanks.

[Svetlin.Nikolov]

Hey,

Both the horizon noise and the uneven ocean surface inside/outside the container should be fixed now. Let me just underline that using the same ocean subdivs as in very early Phoenix 3 revisions would consume completely different amounts of RAM because the ocean algorithms now work in a completely different way. You will get a lot more polys with new Phoenix versions, so you should use lower ocean subdivs to get the same level of detail.

Regarding scale - indeed this is what I mean - is the simulator in real world scale. If the units are meters, is it expected that the simulator is 800 x 200 meters wide? Wouldn't this mean that the waves are in the vicinity of 10-20 meters tall? :O In this scale, it could be the huge scale making the foam appear to slide backwards over the waves. It's just a wild guess, but would increasing the Foam's surface lock change the behavior?

I am thinking about a better way for future Phoenix versions for stitching wild ocean waves simulators into the infinite ocean. My thoughts on this might help you figure the right direction. So there is the simulator, using wave force driven by oceantex1, producing real simulated waves, writing them and reading them from cache. There is also the infinite ocean surface, completely flat by default, which you can displace using oceantex1 as well. Now, the first problem is that the Simulator and the infinite ocean are first meshed together, and them displaced. So you have the simulated waves inside the simulator, and the infinite flat plane of the ocean, before applying any displacement. If you enable the ocean displacement now, the infinite ocean will get the waves from the ocean tex, and the simulator will add these waves on top of its simulated waves, so it will basically have double waves, stacked over one another. So you need to tell the displacement to work only on the infinite ocean surface, and to not displace the waves inside the simulator. This can happen even right now - you have the different options for displacement fade in the rendering rollout. You can use e.g. a box, covering the entire simulator, made non-solid to the simulation and not renderable, and set it as fade geometry, suppressing the displacement inside it, eventually with a smooth fade out. So this way you can have simulated waves inside the container, coming from oceantex1 and the wave force, and fake displaced waves for the infinite ocean, again coming from oceantex1. Currently, using this method, the transition between the simulator and the ocean won't be smooth and it might need trial and error for several reasons, the most important one being that the wave force does not create exactly the same simulated waves like the ocean texture. E.g. if you simulate using oceantex1 for the wave force, rendering with displacement Off would look one way, and the ignoring the simulated cache by using Pure Ocean and then enabling displacement from oceantex1 would look differently. I currently have a test code branch where I made the wave force create simulated waves looking very much like the displacement and this would allow better blending between a stormy sim and stormy ocean.

In summation - you would have some issues at the border currently; the waves inside the simulator and outside it would not behave quite the same with a current Phoenix but I think this can be improved in the future; and also depending on the resolution of the sim - you would have different detail between it and the infinite ocean.

You could bring the detail between the infinite ocean and the sim closer by applying another displacement over the entire thing - both the ocean and the simulator. Say an oceantex2, with much smaller waves and finer detail. However, if you use displacement fadeout to suppress the large waves of oceantex1 inside the simulator, the question is where to plug oceantex2? I think you should be able to do this entirely in the material editor - after turning off displacement fade, you should be able to use the Scaling texture slot of oceantex1 and plug a V-Ray distance tex there, which would do the same thing as the displacement fade - you can use it to create a grayscale mask where the simulator would be black and the ocean would be white. And then, finally, you can plug this oceantex1 + scaling distance tex into a comp tex, together with the fine-detailed oceantex2, and plug the result into the simulator's displacement.

This is how I imagine it would work currently and I hope to have time to get back to making the wave force produce closer result to displacement. Will also check the docs - you can have a seamless transition between flat simulator and infinite ocean right now, but when the wave force comes into play, the transition will not be smooth and you might have to count on low camera angles or post, in addition to what I wrote above.

Hope this helps!