Houdini 20.5 Galleries Materials gallery

Ocean Surface

This material gives the appearance of an ocean surface.

This material creates the appearance of an ocean surface. It is designed to work with spectra created with the Ocean Spectrum SOP. There are several parameters to control the surface properties of the ocean waves, as well as a layer of foam which rests on the surface of the ocean.

Tip

For realistic subsurface scattering effects and attenuation, you can use a Uniform Volume material for the space below the ocean surface.

Parameters

Ocean Shader

Waves

Wave Min/Max Height

These values allow you to customize the color and diffuse contributions of the ocean waves.

Min

The lowest point on your ocean surface, also known as the “troughs” of the waves.

Max

The highest point on your ocean surface, also known as the “peaks” of the waves.

Diffuse

Diffuse Intensity

The diffuse contribution of the ocean waves themselves. Generally speaking, for realistic waves, this value should be very low. This value is multiplied by the Diffuse Ramp value.

Diffuse Color

The diffuse color of the waves from “trough” to “peak”. A variety of ocean looks can be created by simply customizing this ramp.

Diffuse Ramp

A multiplier on the Diffuse Intensity which allows you to vary the diffuse contribution over the surface of the wave from “trough” to “peak”.

Reflections

Note

Reflections can be enabled/disabled on the Settings tab. For a more detailed explanation of reflection parameters, see the Surface Model VOP help page.

Reflect Intensity

How reflective the surface of the ocean is. For realistic waves, this will typically be a very high value.

Reflect Color

The color which will be used to tint the reflective contribution of the wave.

Reflect Roughness

The bluriness of the reflective component of the waves. For realistic waves, this value will typically be quite low, resulting in sharp reflections on the surface of the ocean.

Reflect Minimum

To maintain realism, the ocean surface creates different amounts of reflection based on the angle with which you are viewing the waves. To maintain a desired look, you can set a minimum amount of reflection which will prevent the reflective component from falling below this value, regardless of viewing angle.

Refractions

Note

Refractions can be enabled/disabled on the Settings tab. For a more detailed explanation of refraction parameters, see the Surface Model VOP help page.

Refract Intensity

How visible the refractive component of the ocean surface is. For realistic waves, this value will generally be quite high.

Refract Color

The color which will be used to tint the refractive contribution of the wave.

Refract Angle

The bluriness of the refractive component of the waves. For ocean waves, this value will often be between 1-3. However, for very clear water it would be reasonable to use even lower values.

Refract Minimum

To maintain realism, the ocean surface creates different amounts of refraction based on the angle with which you are viewing the waves. To maintain a desired look, you can set a minimum amount of refraction which will prevent the refractive component from falling below this value, regardless of viewing angle.

Note

Attenuation can be enabled/disabled on the Settings tab.

Attenuation Color

The color to tint the light passing through the ocean surface.

Attenuation Density

The density of the ocean surface. Larger values will make the ocean seem more opaque.

Foam

Foam Particles

The filename of the particles representing the ocean foam, usually created with the Ocean Foam SOP. Every shading point will lookup nearby foam particles according to their radius and accumulate its foam pattern.

Particle Radius Scale

A scale on the particle radius applied before looking up foam particles around a shading point. Increase this value and decrease Particle Alpha to smooth out the look of the foam.

Particle Alpha

The amount of opacity each particle will contribute. Increase this value for a thicker foam layer.

Particle Alpha Ramp

A ramp over the lifespan of the foam particle that further scales the Particle Alpha.

Diffuse

Streak Intensity

The visibility of the foam streaks on the surface of the ocean. Essentially, the diffuse contribution of the foam streaks.

Streak Color

The color of the foam streaks.

Whitecap Intensity

The visibility of the whitecaps on the peaks of the waves. Essentially, the diffuse contribution of the whitecaps.

Whitecap Color

The color of the whitecaps.

Reflections

Note

Reflections can be enabled/disabled on the Settings tab. Additionally, these values are scaled by the overall visibility of the foam (Streak Intensity and Whitecap Intensity), excluding the color values. For a more detailed explanation of reflection parameters, see the Surface Model VOP help page.

Reflect Intensity

How reflective the foam layer is.

Reflect Color

The color which will be used to tint the reflective contribution of the foam.

Reflect Angle

The bluriness of the reflective component of the foam.

Reflect Minimum

To maintain realism, the ocean surface creates different amounts of reflection based on the angle with which you are viewing the foam. To maintain a desired look, you can set a minimum amount of reflection which will prevent the reflective component from falling below this value, regardless of viewing angle.

Refractions

Note

Refractions can be enabled/disabled on the Settings tab. Additionally, these values are scaled by the overall visibility of the foam (Streak Intensity and Whitecap Intensity), excluding the color values. For a more detailed explanation of refraction parameters, see the Surface Model VOP help page.

Refract Intensity

How visible the refractive component of the foam layer is. For realistic foam, it is reasonable to set this value lower than the Refract Intensity of the waves.

Refract Color

The color which will be used to tint the refractive contribution of the foam.

Refract Angle

The bluriness of the refractive component of the foam. For realistic foam, it is reasonable to set this value higher than the Refract Angle of the waves.

Refract Minimum

To maintain realism, the ocean surface creates different amounts of refraction based on the angle with which you are viewing the foam. To maintain a desired look, you can set a minimum amount of refraction which will prevent the refractive component from falling below this value, regardless of viewing angle.

Note

Attenuation can be enabled/disabled on the Settings tab.

Attenuation Color

The color to tint the light passing through the foam layer.

Attenuation Density

The Density of the foam layer. Larger values will make the ocean seem more opaque.

Streaks

Foam Sharpness

How sharp the edges of the foam are. High values will create a sharper more web-like pattern, low values will create a softer, rounder pattern.

Filter Scale

How much to filter the streak pattern to avoid aliasing artifacts when viewed from a distance.

Frequency

The frequency of the streak pattern.

Offset

How much to offset the streak pattern.

Streak Direction

The direction in which to stretch the Frequency to stretch out the foam in that direction. Setting this to the prevailing wind direction or wind direction plus 90 degrees can give interesting effects.

Streak Bias

The amount of Frequency stretching to do along the Streak Direction.

Whitecaps

Intensity Ramp

The whitecaps are generated from a “cusp” value which exists on the peaks of most of the waves created by the Ocean Evaluate SOP. However, depending on the desired look of your ocean, you may not want all of the waves to have a whitecap element. This ramp can be used to adjust which waves will appear to have whitecaps as well as the overall intensity of the whitecap mask. Typically, the lower values can be clamped to zero to avoid whitecaps from appearing on very small waves.

Bubbles

Filter Scale

How much to filter the bubble pattern to avoid aliasing when viewed from a distance.

Frequency

The frequency of the bubble pattern.

Offset

How much to offset the bubble pattern.

Foam Displacement

Note

These values are scaled by the overall visibility of the foam (Streak Intensity and Whitecap Intensity).

Streak Amount

The amount to displace the streak pattern on the surface of the waves. For wide shots, it may not be necessary to displace the foam at all.

Whitecap Amount

The amount to displace the whitecaps on the peaks of the waves. For wide shots, it may not be necessary to displace the foam at all.

Bump Only

Modifies the normals of surface and doesn’t do any true displacement.

Displacement

Spectrum Geometry

The merged Ocean Spectrum outputs representing the ocean surface.

Mask Geometry

The merged volumes representing masks for the ocean surface. These override any masks found in Spectrum Geometry, allowing the use of animated masks with static spectrum geometry.

Anti-Alias Blur

The shader automatically uses downsample ocean spectrum when evaluating larger shading samples in the distance. This parameter scales the size of those shading samples in the calculation and controls how quickly it transitions to lower-frequency samples. Decrease this value for more detail in the distance at the potential risk of aliasing.

Downsample

Downsamples the input ocean spectra before shading.

Time

The time at which to evaluate the input ocean spectra.

Add Bump To Ray Traced Displacements

When True Displacements is enabled, this toggle will add bump to the displacement, adding to the effective detail of the displacement map without incurring the cost of increased shading quality.

Displacement Bound

The maximum bound that the displacement shader will move geometry.

Displacement Space

The space in which you specify displacement bounds.

Re-Dice Displacements

With extreme displacements, you may get micropolygons which are stretched out of shape. With this option enabled, the displacement geometry is re-measured after a trial displacement. The result is micropolygons with a more uniform size, which can result in higher quality images.

Note

This option is more costly because the displacement shader may be run twice during the dicing process.

True Displacements

Whether the VEX variable P will be moved during rendering or whether bump mapping will be performed.

Settings

Enable Reflections

Whether reflections will be calculated by the shader.

Reflect Lights

Whether lights will be considered as part of the reflection evaluation.

Reflect Objects

Whether objects will be considered as part of the reflection evaluation.

Reflection Quality

The sampling quality for raytraced reflections when Reflect Objects is on. Larger values will cause more raytracing samples to be sent for this reflection layer, increasing quality but also shading time.

Reflection Component

The name of the reflection component to be exported by the Mantra ROP.

Enable Refractions

Whether refractions will be calculated by the shader.

Refract Lights

Whether lights will be considered as part of the refraction evaluation.

Refract Objects

Whether objects will be considered as part of the refractions evaluation.

Refraction Quality

Sampling quality for raytraced refractions. Larger values send more raytracing samples.

Refraction Component

The name of the refraction component to be exported by the Mantra ROP.

Note

For a more detailed explanation of Caustic and Fresnel parameters, see the Surface Model VOP help page.

Enable Fake Caustics

With this option enabled, the ocean surface will create semi-transparent shadows that attempt to approximate the amount of light that would be transmitted if real caustics were rendered. If you're rendering real caustics using an Indirect Light, turn this parameter off.

Min Shadow Intensity

The minimum shadow intensity to use for fake caustics. Increase this to darken the lightest part of the shadow.

Max Shadow Intensity

The maximum shadow intensity to use for fake caustics. Decrease this to lighten the darkest part of the shadow.

Conserve Energy

Ensures that the surface reflects no more light than it receives. This is important in physically based rendering and raytracing to ensure the illumination in the scene does not increase as the number of raytracing bounces increases.

Fresnel Blending

Turns on Fresnel blending, where the reflection and/or refraction amount varies based on the viewing angle to the surface. You can control the proportion of Fresnel blending for each component through the minimum parameters on the different tabs.

Inside IOR

The interior index of refraction for use in physical Fresnel computations. Water has an index of refraction around 1.33.

Outside IOR

The exterior index of refraction for use in physical Fresnel computations. Air has an index of refraction near 1.

See also

Materials gallery

  • UV Map

    This is basic diffuse material, no specular, with a map of colored and numbered squares.

  • Background Plate

    Implements an example shader for background matte object in Karma.

  • Basic Flame

    A constant material where the density value of the volume drives the color ramp.

  • Basic Liquid

    A reflective refractive material for liquids using ray tracing.

  • Basic Smoke

    A diffuse material designed specifically for volume objects.

  • Billowy Smoke

    A billowy diffuse material designed specifically for volume objects.

  • Checkerboard

    This is a basic material with checked color map.

  • Clay

    This is basic diffuse material without specular.

  • Constant

    This is a constant material with optional maps for color and opacity.

  • Constant Smoke

    A diffuse unlit material designed specifically for volume objects.

  • Decal

    This material applies a texture an object.

  • Dust Puff

    A material suitable for using particles to render smoke or fog.

  • Fluid Fire

    A constant material where the density value of the volume drives the color ramp.

  • Glow

    This is a constant material, which represents the angle between the camera and the surface normal.

  • Liquid Smoke

    A diffuse material designed specifically for interior of volume liquids.

  • Ocean Surface

    This material gives the appearance of an ocean surface.

  • Shadow Matte

    Implements a shadowmatte shader that occludes geometry behind the surface being rendered.

  • Show Normal

    This is a constant material showing the value of the surface normal’s x y z directions in a red, green, blue color.

  • Show Shading Point

    This is a constant material showing the value of the shading point’s x y z values in a red, green, blue color.

  • Show Tangent

    This is a constant material showing the value of the surface tangent’s x y z directions in a red, green, blue color.

  • Show UV

    This is a constant material used to verify an objects texture coordinates.

  • Sprite Fog

    A material suitable for using particles to render smoke or fog.

  • Uniform Volume

    Renders a closed surface as a volume consisting of a uniform fog.

  • Wispy Smoke

    A wispy diffuse material designed specifically for volume objects.