A couple of purchasing questions

[ben_hamburg]

Hi there,

so we now have a project with lots of ocean scenes and some boats/ships and other stuff reacting to it.
Naturally we first looked into real flow, but apart from the price the learning curve is pretty steep and due to simulation times it´s hard to tell, if we can get everything done in time with it.
Apart from we were having trouble getting the right in how to implement the sims correctly in Max without the use of any additional tools like Frost or Krakatoa.

So I had a look at Phoenix and it looks promising as an alternative for our project.

I started to test the demo and some pros and cons immediately popped up, I´d love to get some info on these asap!

Pro: The implementation of the infinite ocean shader seems pretty intuitive.
Con: If I use the displacement map in the Sim, the Detail doesn´t hold up in closeup (Upped the levels in the shader to 64). Is this a limitation of the demo or hoe else can I increase the detail in the surface?

Pro: Sim times seem to be pretty fast compared to Real Flow. At least with the settings I was able to try in the demo. Its definitely way faster to visualize general movements in the liquid, then in Real Flow.
Con: Splashes seem to be way to large to be realistic for a large ocean surface (tried with a boat dummy).
Is this a limitation of the demo aswell, due to grid size, or am I misusing some meshing options?

Pro: Ability to render and shade foam included!
Con: Hard to tell how many particles I would need to make it look realistic. I´ve seen some test videos o your youtube channel (the one with the revier for eample), that seemed quite convincing.
So are there restrictions as to how many particles I could render and if so, how do I determine those restrictions so I can plan ahead?

There are also some other questions, which concern the actual project we´re working on:

1. Let´s say I want to animate a fast moving boat across the ocean surface - is there a possibility to link the Phoenix Object to the boat, so I only have to animate a relatively small grid?

2. I have a couple of scenes were I´d like to have waves crashing on static objects (Rocks, for example).
I found this post on the official forum, but can´t access the files posted there to check for myself and would like to know how well the tips work now?
http://forums.chaosgroup.com/showthr...bject-in-ocean
Another option would be to use a similar setup like in a Real Flow Tutorial I found:
Create a Liquid emitter emitting particles in regular intervals, thus creating waves crashing on a rock formation. That should work in combination with the infinite ocean as well, right?

3. Last but not least:
Is it possible to create foam maps from the sim like in Realflow? I´m just afraid that rendering millions of foam particles might be too slow on our schedule...

I really hope that Phoenix can work for this project as our fluid solution...so we can get smoke and fire for free....

[ben_hamburg]

I did some more reading in the meanwhile and i think I can answer a couple of my questions myself:

1. Foam Maps.
There is the PHXMapper helper...I guess that way I can build a shader with some fake foam via the displacement texture (for white crests), right?

2. Displacement detail.
I read in another post, that the unextended part of the simulation can only get as much detail as its cell size allows, right?
So if i get too close, i´ll probably have to add in more detail via bump mapping (maybejust use the animated displacement map created with the PHXmapper with a higher tiling...

[Ivaylo Katev]

Pro: The implementation of the infinite ocean shader seems pretty intuitive.
Con: If I use the displacement map in the Sim, the Detail doesn´t hold up in closeup (Upped the levels in the shader to 64). Is this a limitation of the demo or hoe else can I increase the detail in the surface?

in the last week we did some improvements in this area, adaptive subdivision that produces high detailed result with less triangles compared to the uniform subdivision method.
but the subdivision works only for the extended part, as you already know, in the simulated part you can workaround this using a turbosmooth modifier, one user suggested this solution and it works pretty well.

Pro: Sim times seem to be pretty fast compared to Real Flow. At least with the settings I was able to try in the demo. Its definitely way faster to visualize general movements in the liquid, then in Real Flow.
Con: Splashes seem to be way to large to be realistic for a large ocean surface (tried with a boat dummy).
Is this a limitation of the demo aswell, due to grid size, or am I misusing some meshing options?

the splash size is controllable, in the simulation and in the rendering too. the demo limitation in this area is the splash count, it's 10 000 in the demo, that is really a small number, in the next release we will change it to 500k. for good production result you need at least 1M particles.

Pro: Ability to render and shade foam included!
Con: Hard to tell how many particles I would need to make it look realistic. I´ve seen some test videos o your youtube channel (the one with the revier for eample), that seemed quite convincing.
So are there restrictions as to how many particles I could render and if so, how do I determine those restrictions so I can plan ahead?

as i said in my previous answer, about 1M is the minimum for production, 10-20M is normal (for foam and splash), 100M and even up to 1G is also possible for smoke rendering (you can use the foam shader to render smoke)

1. Let´s say I want to animate a fast moving boat across the ocean surface - is there a possibility to link the Phoenix Object to the boat, so I only have to animate a relatively small grid?

yes, this video is exactly a simulator bound to the ship that simulates small area around it. the foam leaves the simulation area but continues to behave realistic, because it is particle based and is able to simulate outside the grid

2. I have a couple of scenes were I´d like to have waves crashing on static objects (Rocks, for example).

the displacement waves are fake and can't react with the simulation. however one user made a video with oil platform and the max forces were used to produce the needed activity.

Is it possible to create foam maps from the sim like in Realflow? I´m just afraid that rendering millions of foam particles might be too slow on our schedule...

you can convert the foam particles into map, if this is what you need, the particle texture does exactly this. another option is to use the "render as fog" option, it produces a 3d texture that is rendered using the same technique that we use to render smoke.
however, i really doubt that any of these solutions is faster than the point shader.

[ben_hamburg]

Hi Ivaylo,

one of the things I love most about Chaosgroup is the incredible support, thanks for answering so quickly and thoroughly!
I think this is all I need to know for now and we´ll go with Phoenix FD.
I´ll most certainly come back with more questions though!

[vlado]

By the way, if that was not clear, we can get you a full evaluation license if you want to do more thorough testing.

Best regards,
Vlado

[ben_hamburg]

We already obtained a license, but good to know for future products!
We´re still having problems with licensing (we´re already contact with support), but in the meantime and til I can post in the official forums, I have some more questions:

Since we have a couple of scenes with static objects interacting with the infinite ocean, I´m looking into ways to do this properly.

Ivaylo mentioned two possible solutions:
1. Add a wind force to get some splashes around the objects.
2. Use the PHX Mapper to get real waves from the Ocean texture.

I tried to recreate both solutions and I got basically the same problem with both: Visible borders where the grid meets the infinite ocean.
I haven´t played around much with the settings yet, but I was wondering if there was an easy way to...

A) Use some sort of falloff where the external force influences the grid (tried to use the decay option in the wind force, but that didn´t work so far), if going with solution 1.
B) Map the influence of the ocean texture map if going with solution 2, so it just influences an area close to the objects.

[ben_hamburg]

Little update: Licene is working now and forum access has been updated, so Í´ll post future questions there.

[Ivaylo Katev]

the problem with the borders is really expected, here kimgar explains how the borders are kept invisible.
of course you can try to create fade out for the texture driving the waves using the VRayCompTex and VRayDistanceTex