whitewater setup on deformed wave

[EuniceC]

Hi, 

I need some advice on how to create whitewater on a mesh? I created a deformed wave using a grid and Attribute VOP instead of the ocean tools. The reason for that is that I wanted my wave to curve in an unnatural way. I'm trying to set up whitewater, spray and mist for that wave at the moment and I'm not sure where to start. I can't just click whitewater from the tools because my mesh is not a flip sim. What's the best way to go about this? I thought of using vdb from polygons but then I'm stuck again and not sure where to go from there.

Please help! Any advice will be appreciated!

Thanks

[moneitor]

something that comes to my mind is that you could create a mask in you mesh based on the velocity of the points and the curvature, then scatter some points in that masked area and use pops to create your white water, I did a white water setup that way here at my job for non hero shots and is working pretty nicely. If on top of your animated wave you are using an Ocean spectrum then is much more easy, because the ocean spectrum will give you a bunch of useful attributes, like cusp, velocity, etc... Then inside VOPs in a pop network you can use those attributes to drive the motion of your particles, which I think is basically what the white water solver does, but instead of using the attributes from your ocean spectrum, is using the attributes from your flip simulation.

 

Let me know if this make sense.

[EuniceC]

20 minutes ago, moneitor said:

something that comes to my mind is that you could create a mask in you mesh based on the velocity of the points and the curvature, then scatter some points in that masked area and use pops to create your white water, I did a white water setup that way here at my job for non hero shots and is working pretty nicely. If on top of your animated wave you are using an Ocean spectrum then is much more easy, because the ocean spectrum will give you a bunch of useful attributes, like cusp, velocity, etc... Then inside VOPs in a pop network you can use those attributes to drive the motion of your particles, which I think is basically what the white water solver does, but instead of using the attributes from your ocean spectrum, is using the attributes from your flip simulation.

 

Let me know if this make sense.

Thanks for the reply!

Would you elaborate more on the part about creating a mask?

I have attached my hip file here so you can see how I've set up my wave. I was thinking perhaps I can use the shelf tool (Flip Fluid from Object) and make a flip sim from my scattered points there and then just use the whitewater shelf tool. I'm not sure if this will actually work. From my understanding, the scattered points are already the particles?

WaveDeformerTest.hip

[moneitor]

Ill check the file tonight when I get back from work.  The scattered points are just the emitters of your particles, not the particles themselves.

I just opened the file very quickly but I don't see any animation on the waves, is that gonna be a still? or you were thinking on build your fluid simulation from there? because right now I see you are creating the mask, but there is no velocity in the points which of course wont give you any nice initial motion on your points.

Edited July 25, 2017 by moneitor

[EuniceC]

Alright!

[moneitor]

I setup an example of how you probably could create a mask, is something I did very quickly so of course is not something you can actually use, but maybe it help you thinking about a way to create your setup, after the emittion, most of your job will be in pops, finding a way of making the particles "float" on the surface of your geo, is not that hard though.  Maybe on the weekend with time I can prepare something.

WaveDeformerTestQuickMask.hip

Edited July 25, 2017 by moneitor

[EuniceC]

27 minutes ago, moneitor said:

I setup an example of how you probably could create a mask, is something I did very quickly so of course is not something you can actually use, but maybe it help you thinking about a way to create your setup, after the emittion, most of your job will be in pops, finding a way of making the particles "float" on the surface of your geo, is not that hard though.  Maybe on the weekend with time I can prepare something.

WaveDeformerTestQuickMask.hip

That's great. I will experiment with it. At least now I have an idea of which direction to work towards. Thanks a lot! Do post your example if you have time to make something over the weekend  

[EuniceC]

3 hours ago, moneitor said:

Ill check the file tonight when I get back from work.  The scattered points are just the emitters of your particles, not the particles themselves.

I just opened the file very quickly but I don't see any animation on the waves, is that gonna be a still? or you were thinking on build your fluid simulation from there? because right now I see you are creating the mask, but there is no velocity in the points which of course wont give you any nice initial motion on your points.

Actually, the waves are still and I was thinking of generating the whitewater particles through the movement of the cusps. Clearly that was not enough and it probably wouldn't work. I have animated the wave to fit what I want and modified my wave accordingly to achieve the curvature scatter points. Now it's emitting particles, I just have to make the points float. 

I'm think to make the particles float, I have to create a surface VDB on the mesh and connect to the pop network?

Here is the updated file

WaveDeformerTestQuickMask_edit2.hip

[moneitor]

you could use a vdb and them move the points using the gradient of the vdb, or you could use your mesh and then use a ray vop to keep the points in the surface, but with a static mesh I won't expect the points to have a very cool motion though.

[EuniceC]

16 hours ago, moneitor said:

you could use a vdb and them move the points using the gradient of the vdb, or you could use your mesh and then use a ray vop to keep the points in the surface, but with a static mesh I won't expect the points to have a very cool motion though.

I tried something using vdb and getting the cross product of velocity vector and gradient. I then used Ray SOP for the whitewater emitter. I used "OUT_EMITTER" from oceansurface node as my whitewater emitter. I still couldn't get the effect of whitewater where it moves more randomly but at the same time follows the movement of the mesh. At the moment all they do is fall downwards. I tried various methods but it's still doing the same thing. 

For my flip, I used "OUT_VDB" for my flipfluidobject. I want to achieve something like the one in the reference picture, or at least something similar. 

 

WaveDeformerTestQuickMask_edit2.hip

[moneitor]

I did again something quick in my part of the setup, nothing fancy but is to give you an idea, I didnt did this in your part of the setup because I dont think with your current setup would be posible to create nice motion on the particles, unless you sculpt some forces, because basically you dont have a nice initial velocity for your points. regarding the floating particles, I am using an intersect, for sure a VDB would be faster, but in the office I have limited access to H16 so I had to do something very rough and quickly to give you an idea.  It got lots of errors, but maybe serve as an starting point.

WaveDeformerTestQuickMask_edit2.hip

[EuniceC]

On 7/27/2017 at 7:37 PM, moneitor said:

I did again something quick in my part of the setup, nothing fancy but is to give you an idea, I didnt did this in your part of the setup because I dont think with your current setup would be posible to create nice motion on the particles, unless you sculpt some forces, because basically you dont have a nice initial velocity for your points. regarding the floating particles, I am using an intersect, for sure a VDB would be faster, but in the office I have limited access to H16 so I had to do something very rough and quickly to give you an idea.  It got lots of errors, but maybe serve as an starting point.

WaveDeformerTestQuickMask_edit2.hip

This is amazing! Sorry for the late reply. I have been working on the wave scene and have finally achieved a desirable look. Special thanks to @moneitor for your help! 

[piefaced]

This is amazing thank you!