Houdini 22.0 Nodes Copernicus nodes

Height to Shadow Copernicus node

Creates shadows using a virtual light source.

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Since 21.0

This node generates shadows using a virtual light source. The node provides approximate shadows based on the given height field. This node is useful for shading and texture synthesis.

For each pixel, this node applies a light source and then determines how occluded that light source is based on the height values of its neighboring pixels. For example, if you're standing on pixel (450, 450) and that pixel’s in a valley with mountains around it, the light source is occluded because the mountains block the sun’s rays.

This node is similar to the Height to Ambient Occlusion COP (especially when its Sample Count is 1), but also lets you control the light position.

Tip

Wire a noise node like the Fractal Noise COP into this node.

Parameters

Space

The space in which to interpret light position, direction, and normal parameters.

Local

Uses the image’s local space.

World

Uses world space.

Height

Height Map Scale

The scale to apply to height values before computing shadow occlusion.

Quality

Step Scale

How many steps (in buffer space) to take along the rays to determine if a pixel’s occluded. Higher values create less steps and therefore cook faster, but may miss thin features since the steps are more spread out. Lower values create more steps, which are closer together.

Light Source

Type

The light source profile to use.

Disk

Sets the virtual light source as a disk, which distributes lights over the area of a disk. This corresponds to an area light as used in rendering engines.

Sphere

Sets the virtual light source as a sphere, which distributes lights along the outside surface of a sphere. This corresponds to a sphere light as used in rendering engines.

Directional

Sets the virtual light source as a directional light, which emits a point light source at infinity. This corresponds to a directional light as used in rendering engines.

Single Sided

When the light source is Disk, ignores light from the back side of the disk.

Radius

The radius in image space of the light source. This parameter is available for Disk and Sphere light sources.

Angular Size

The angular radius in degrees of the Directional light source.

Transform

Disk and Sphere

Use

The coordinates to use to control the position of Disk and Sphere light sources.

Spherical

Use spherical coordinates , which use distance and two angles to define a point.

Cartesian

Use Cartesian coordinates , which are the X, Y, and Z locations along the axes.

Distance

When Use is Azimuth/Altitude/Distance, this is the distance in image space between the origin and the light source.

Altitude

When Use is Azimuth/Altitude/Distance, this is the angle in degrees of the light source relative to the XY-plane.

Azimuth

When Use is Azimuth/Altitude/Distance, this is the angle in degrees of the light source relative to the X-axis on the XY-plane.

Position

When Use is Position, this is the 3D position of the light source.

Light Normal

The normal direction of the Disk light source.

Directional

Use

The coordinates to use to control the direction of a Directional light source.

Azimuth/Altitude

Uses two angles to define the light direction.

Direction Vector

Uses a 3D direction vector.

Azimuth

When the directional Use parameter is Azimuth/Altitude, this is the angle in degrees of the light direction relative to the X-axis on the XY-plane.

Altitude

When the directional Use parameter is Azimuth/Altitude, this is the angle in degrees of the light direction relative to the XY-plane.

Direction

When the directional Use parameter is Direction Vector, this is the 3D light direction.

Inputs

height

The original height layer from which to calculate shadows.

Outputs

shadow

The shadowed layer.

See also

Copernicus nodes