Stormy Sea

This tutorial explores how to create a stormy sea (with waves around 1.5 meters tall) and simulate a ship sailing at sea as Active Bodies. The ship is powered by an Active Body Thruster, no manual keyframing is needed for the ship animation.

This simulation requires 5.01.00, Build ID: 20220706 and V-Ray 6 for 3ds Max 2018 at the least. You can download official Phoenix and V-Ray from https://download.chaos.com. If you notice a major difference between the results shown here and the behavior of your setup, please contact us using the Support Form.

The Download button below provides you with an archive containing the scene files.

Download Project Files

Scale is crucial for the behavior of any simulation. The real-world size of the Simulator in units is important for the simulation dynamics.

Large-scale simulations appear to move slower, while mid-to-small scale simulations have lots of vigorous movements.

When you create your Simulator, check the Grid rollout where the real-world sizes of the Simulator are shown. If the size of the Simulator in the scene cannot be changed, you can trick the solver into working as if the scale is larger or smaller by changing the Scene Scale option in the Grid rollout.

The Phoenix solver is not affected by how you choose to view the Display Unit Scale — it is just a matter of convenience. Setting the units to Meters is a reasonable choice for this setup.

Go to Customize → Units Setup and set Display Unit Scale to Metric Meters. Also, set the System Units so that 1 Unit equals 1 Meter.

The final scene consists of the following elements:

1. A Ship geometry and its active bodies clone;
2. A Phoenix Liquid Source;
3. Three Particle Shaders for the Foam, Splash and Mist particles respectively;
4. A Box geometry used in the Liquid Source for the foam emission;

5. A V-Ray Plane used as an infinite ground surface - sometimes the V-Ray Plane might cause flickering at the ocean border, so consider using a very large regular plane geometry placed below the liquid simulator instead;

6. A Wave Force to drive waves from water;
7. An Active Bodies helper for Active Bodies simulation.
8. An Active Body Thruster helper to move Active Bodies (the Ship) with an engine force.

9. A Phoenix Liquid Simulator;

10. A Phoenix Fire / Smoke Simulator for rendering the fog;

11. A Plain Force as a wind force in the scene to blow the Splash/Mist;

12. A V-Ray Physical camera (VRayCam_RnD) for look development;

13. A V-Ray Physical camera (VRayCam_Final) for the final animation;

14. V-Ray Light Dome for lighting;

Here we have prepared a fishing trawler geometry for the simulation. It is a solid, single-mesh, water-tight model. If you apply a STL Check Modifier to the model, no errors appear.

The pivot position of the ship model is fine-tuned, and if we enable the Override Center of Mass option of its Phoenix node properties, the Active Bodies helper creates the Center of Mass helper based on the pivot of the ship automatically. So the ship can maintain balance in still water.

The ship is around 14.5 meters in length, 3.9 meters in width and 8.5 meters in height.

The polygon faces of the ship are assigned with different face IDs, and applied with a MultiSub-Object material to them. Each face ID is with different diffuse color and material.

We assign two different VRayLight materials to ID 7 and ID 9.

On top of the MultiSub-Object material (Ship_mat), let's add a VRayBlend material (rename it to Ship_old_mat) to blend with a rust material (Rust_mat). The Blend amount is mapped by using a VRayDirt texture. This way we can have a rusty fishing trawler.

Set the Animation Length parameter appearing in the Time Configuration window to 230, so that the Time Slider goes from 0 to 230.

The image here is the final render in this tutorial. The wave can reach up to 1.5 meters in height. The image shows the typical features of a ship sailing in a stormy sea.

When the ship sails against the wind in the sea, it drifts up and down while creating lots of splash and mist. You can see foam patterns forming in the sea.

Let's go through the steps and see how to build these features.

Let's create a Liquid Simulator. Go to Create Panel > Create > Geometry > PhoenixFD > PhoenixFDLiquid. Create a liquid simulator in the scene.

The exact position of the Simulator in this example scene is XYZ: [7.33, 0.0, 0.0].

Open the Grid rollout and set the following values:

Select the Dynamics rollout of the PhoenixFDLiquid. Enable the Initial Fill Up %. Set the value to 50.0.

This way the simulator is filled with liquid at the start of the simulation.

Select the Output rollout of the PhoenixFDLiquid.

Enable the Particle Age channel for the Splashes and the Foam particle systems.

Select the Preview rollout of the PhoenixFDLiquid simulator. Enable the Show Mesh option. Disable the Particle Preview option.

As for the Rendering rollout, switch the Mode to Cap Mesh.

This way only the top part of the liquid surface will be shown and allow for easier iteration.

The ship is provided with the Stormy_sea_max2020_start scene.

The exact position of the ship is XYZ: [ -1.64, 0.0, 4.36].

From Create Panel > PhoenixFD > Active Bodies, create an ActiveBodies helper in the scene.

Add the Ship geometry to the Active Bodies list.

Adding the ship to the Active Bodies list creates a center of mass gizmo in the scene. The gizmo's position is computed by the solver automatically.

With the Ship geometry selected, right-click and open the Chaos Phoenix Properties. Use the Closest preset - Ship Hull to set the ship density to 500.0 kg/m3.

Choose the Ship Hull preset because it is a reasonable choice for a start-up. We can fine-tune the density later.

Enable the Active Bodies option in the Dynamics rollout of the simulator. Link the Active Body Solver to the Phoenix Liquid Simulator.

Select the Simulation rollout of the Phoenix Liquid Simulator. You don't have to simulate the full length of the animation. Only a sample is enough, so set Stop Frame to 100.

Press the Start button to simulate.

The ship is tilting at sea, almost capsizing.

As you can see, the position of the automatically generated COM is too high, high above the waterline. The improper position of the COM makes the ship hard to maintain balance.

With the Ship geometry selected, right-click and open the Chaos Phoenix Properties. Set the Specify Density parameter to 300.0 kg/m3.

Enable the option Override Center of Mass.

With the new density and COM, let's run the simulation again.

Now the ship doesn't sink, and it can stabilize on the sea surface. The ship is ready to face the wave force.

Go to Create Panel > Create > Helpers > PhoenixFD. Create a WaveForce in the scene.

Enable the Massive Wave Force option.

Increase the Fluid Freedom to 1.0.

Create a PhoenixFDOceanTex into the Ocean map slot of the WaveForce. Rename the texture to OceanTex_WaveForce.

Here are the values for the OceanTex_WaveForce parameters set for the tutorial:

Now we want to simulate the WaveForce in the scene, so we enable the Timeline option for both Start Frame and Stop Frame, to simulate the full length of the animation.

Run the simulation again.

Here is a preview animation of the simulation from Camera-RnD. We see the ship floating in the sea, while the waves come to flap on it. In the later frames, we even see the collapsing wave forming a tube or barrel. So those waves are a plunging type of breaking waves.

With the Liquid Simulator selected, go to the Preview rollout. Enable the Velocity Streamlines option.

By doing so, we can visualize the velocity changes due to the WaveForce acting on the liquid particles. When the depth of the simulator is deep enough, we can see underwater cycles spinning passing through.

Here is the preview from the Front view with Velocity Streamlines preview option.

We are trying to create a ship sailing in the middle of the sea, not near the shore. So let's adjust the WaveForce for forming more spilling waves than plunging ones. With the WaveForce selected, reduce the Fluid Freedom to 0.96.

Run the simulation again.

This table shows the characteristics of two extreme conditions in this tutorial. Choosing other in-between values for the Fluid Freedom to meet your project requirement is also an option.

Now the waves look more like spilling waves. We don't see a barrel in the waves.

Let's give power to our fishing trawler.

Go to Create Panel > Create > Helpers > PhoenixFD. Press the ABThruster button and create an Active Bodies Thruster in the scene.

The exact position of the thruster is XYZ: [ -7.33, 0.0, 3.97 ].

With the ABThruster selected, press the None button and choose the ship in the scene. The ship is now powered by the ABThruster.

Reduce its Magnitude to 1.0m. Check both the option for No Rotation and Attached to body.

Run the simulation again.

Here is the preview animation for VRay_Cam_Final. Now we start to see the ship sailing through the waves.

However, the liquid splashes look too strong. The ship's movement is also too dramatic. We can see some liquid mesh being cropped at the top.

With the ship geometry selected, right-click and select Chaos Phoenix Properties. Reduce the Motion Velocity Effect to 0.25.

Run the simulation again.

Now the liquid splash became more gentle. And the ship's movement appears more convincing.

With the liquid simulator selected, go to the Splash/Mist rollout.

Enable the Splash/Mist option. When asked if you'd like a Phoenix Particle Shader generated for the Splash particles, select Yes. This automatically sets up the link between the Splash particles group, the Particle Shader, and the Liquid Simulator.

Rename the new particle shader to ParticleShader-Splash. 

With the simulator selected, in the Dynamics rollout, decrease Time Scale to 0.9 , this will slow down the liquid a bit for aesthetics purposes.

In the Splash/Mist rollout, increase Splash Amount to 800.0 and decrease the Mist Amount to 1.0.

In the Properties section, increase the Max Outside Age to 10.0.

With those new settings, run the simulation again.

To easily spot which particles are which, let's change the color swatches for the different particle types.

Select the PhoenixFDLiquid in the scene and go to its Preview rollout. Disable the Liquid particle preview. Set the Splash, Mist, and Foam to Blue (RGB: 0, 0, 255), Red (RGB: 255, 0, 0), and Green (RGB: 0, 255, 0) color respectively.

Now we start to see splash particles in the simulation.

To make the splashes blend better with the liquid mass, with the simulator selected, in the Properties section of the Splash/Mist rollout, increase the Liquid-Like value to 5.0.

Run the simulation again.

Now we see the splashes blend better with the liquid mesh. As the parameter's name implies, the splashes now became a bit more "liquid-like".

For additional realism of the simulation, we use Phoenix Plain Force, a simple directional force, to simulate the effect of wind.

Go to Create Panel > the Helpers tab > Phenix and add a Phoenix Plain Force.

With the Plain Force in the scene, run the simulation again.

Now the Splash / Mist particles are blown away by the plain force, as the ship sails against the wind.

With the simulator selected, go to the Dynamics rollout. Enable the Simulate Air Effects option.

Run the simulation again.

Although the benefit of enabling the Simulate Air Effects option is very subtle in this case, we see the splash/mist is now blown away by the plain force more easily.

Let's see a front preview of the simulation with the Velocity Streamlines option enabled. We see clearly the Simulated Air Effects indeed act on the area where the grid has no liquid.

To alleviate the chunky looks of the splash/mist particle mass, let's increase the Initial Vel. Rand in the Properties session of the Splash/Mist rollout. Give it a value of 0.3.

When increasing the Initial Vel. Rand, the particles might travel way too far. To compensate that, we also increase Splash Air Drag to 2.0, and Mist Air Drag 3.0.

With those new settings, run the simulation again.

Now the particles are more dispersed, we see less chunky or blobby looking in the splash / mist.

Select the Foam rollout of the Phoenix Liquid Simulator and enable it. A pop out window prompts us to create a Particle Shader for the foam, so select Yes.

Rename the new Particle Shader to ParticleShader-Foam.

With the simulator selected, go to Foam rollout. Set the Foam Amount to 0.05. Set the Birth Threshold to 0.2 m. Decrease the Size to 0.006 m.

Run the simulation again.

Now we start to see foam particles being generated in the scene, but they are shooting upward in an unrealistic way.

With the Simulator selected, go to the Foam rollout. In the Dynamics section, set the Foam Volume to 0. Reduce the Rising Speed to 0.35. Decrease the Falling Speed to 10.0.

Increase the Surface Lock to 1.0.

Now the foam movement looks much more convincing.

Since we have finished the essential settings of the active bodies, splash, mist and foam, let's expand the grid to a larger region.

With the simulator selected, go to Grid rollout. Set Grid size to XYZ: [580, 580, 109].

To add an extra layer of realism to the shot, we like to add foam that exists before the WaveForce kicks in.

From Create Panel > Standard Primitives, create a Box in the scene.

Set the Box's Length to 52.0, Width to 52.0 and Height to 0.1.

Set the segments for Length, Width and Height to 1.

The exact position of the Box is XYZ: [ 7.33, 0.0, 4.67 ].

Right-click on the Box in the viewport and select Object Properties.

Create a Phoenix Liquid Source in the scene by going to Create Panel > Create > Helpers > PhoenixFD > PHXSource.

Set the Emit Mode to Volume Brush. This mode will gradually fill the volume of the emitter with particles.

Press the Add button to choose which geometry to emit and add the Box entry to the Scene Explorer.

When you add the Box to the LiquidSrc Emitter Nodes, a Chaos Phoenix window pops out. Choose the Make Non-Solid button to disable the Solid Object option in the Phoenix properties of the box.

With the LiquidSrc selected, go to Graph Editors/Track View > Curve Editor and set keys to the curve of the source's Brush Effects %.

We set keyframes for this parameter, so that the source brushes out foam particles only in the very first frame. The frames and values are shown in the screenshot.

Here is a table with keyframes for the LiquidSrc's Brush Effects %. 

For the LiquidSrc:

Here's the shading network in the Slate Material. You can see the connections here.

Everything is all set, let's run the simulation.

With the simulator selected, go to Foam rollout. Increase Half Life to 15.0. Set the Max Outside Age to 10.0. In the Patterns section, set the Formation Speed to 0.05. Set Radius to 1.2m.

With those foam settings, run the simulation again.

Now we start to see foam particles distributed over the ocean surface. We are ready for the next phase.

We have a Particle Shader for splashes and foam already. For the Mist particles, we have to create a new Particle Shader manually.

Go to Create Panel > PhoenixFD and press the PHXFoam button to create a new Particle Shader in the scene. Rename it to ParticleShader-Mist.

Press the Add button and pick the Liquid Simulator, then select the Mist particle group. When doing so, a pop out window prompts you to add PhoenixFDLiquid to the Liquid Simulator slot to the shader, press Yes.

Set the ParticleShader-Mist mode to Fog.

With the PhoenixFDLiquid simulator selected, go to the Rendering rollout and switch the Mode to Ocean Mesh.

Increase the Smoothness of the Mesh Smoothing to 2.0.

To add details to the ocean surface, enable the Displacement option. Plug a PhoenixFDOceanTex in the Map slot.

Drag and drop it into the Material Editor as an Instance. (the Copy option creates a copy of this Map - you want to use the same texture in the simulator and in the material editor instead of being forced to deal with 2 separate PhoenixFDOceanTex, so make sure to choose the Instance option). Rename the texture to OceanTex_for_displacement.

Enable the Vert. Fade Level, and set it to 50.0.

Here are the values for the OceanTex_for_displacement parameters that we use in this tutorial:

In the Rendering rollout of the simulator, switch Mode from Cap Mesh to Ocean Mesh. Phoenix prompts the Chaos Phoenix Warning window. Click on Yes to use static default geometry.

Let's take a look at the water material now.

Create a V-Ray Material and assign it to the PhoenixFDLiquid Simulator. Set the Diffuse color to black.

Reflect and Refract colors are set to white - it produces a completely transparent material if the Index of Refraction is set to 1 (which is the IOR of clear air). But let's set the IOR to 1.333, which is the physically accurate Index of Refraction of water.

Keep the Max depth to its default value of 8 for both Reflection and Refraction.

To slightly blur the specular highlights produced by the sources of illumination in the scene, reduce the Reflection Glossiness to 0.95.

If we render now, we'd notice that the water is completely transparent and does not look like ocean water.

Instead, let's switch the Translucency to Volumetric. Set the Fog color to RGB : [46, 75, 102] and set the Depth to 150.0.

Set Scatter color to RGB : [44, 140, 119]. Set SSS amount to 0.5. This produces the type of shading expected in a large body of water containing all sorts of particles that interfere with the light rays.

Run a test render for frame 177 for our current setup. See that the foam on the sea surface is too grainy. Some splash particles are way too big and some foam particles are offset from the ocean surface at the simulator's borders.

For the final simulation, increase the Grid Resolution by lowering the Cell Size.

Open the Grid rollout and set the following values:

Here is the preview animation for the final simulation.

Run a test rendering. See the splashes appear smaller, but they are still slightly bigger than we want. And the offset foam at the border is still there.

Let's fix those issues by adjusting the Particle Shader's settings in the next step.

Adjust the Particle Shaders for Foam, Splash and Mist.

For the ParticleShader-Foam:

For the ParticleShader-Splash:

For the ParticleShader-Mist:

Feel free to adjust the settings for those Particle Shaders, in terms of Size Multiplier and Count Multiplier to fit your artistic taste.

Run a test rendering. You can see now we have much refined foam particles, and enough details in the Splash/Mist area. Let's continue to the next step, turn the environment into a foggy sea.

In order to simulate the fog in the scene we can use a Fire/Smoke Simulator instead of a V-Ray Environment fog.
While you can still use V-Ray Environment fog to achieve a similar result, in order to get a proper blending of the Particle Shader nodes with the fog you will have to enable the Render as Geometry checkbox in the Particle Shader options, which in most cases is slower to render. This is why in this case we will use a Fire/Smoke Simulator to emulate the fog effect.

Let's create one now. Go to Create Panel > Create > Geometry > PhoenixFD > FireSmokeSim.

The exact position of the Phoenix Simulator in the scene is: XYZ: [ -22.0, 0.0, 0.0 ].

Open the Grid rollout and set the following values:

Select the Phoenix Fire/Smoke Simulator, and go to its Volumetric Render Settings.

With the Phoenix Fire/Smoke Simulator present in the scene, let's do a test rendering. 

As you can see, the ship sails in a foggy environment now. But at the same time, the image became underexposed.

In the Render Setup > Render Elements tab, add VRayLightMix render element. This is necessary for relighting the scene in the VFB.

Open the V-Ray Frame Buffer and use the Create Layer icon to add layers for White Balance, Exposure and Lens Effects.

Re-enable both the Depth of field and Motion blur of the VRayCam_Final.

The final image is rendered using the V-Ray Frame Buffer with the color corrections and post effects set to:

Sharpen/Blur:

Lens Effects:

Exposure:

White Balance:

LightMix:

Feel free to use other values for the post effects depending on your preferences.

Alternatively, you can load a Rendering Preset from the Stormy_Sea.vfbl file that is provided in the sample scene.

And here is the final rendered result (from frame 140 to frame 230).