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PxrTangentField

Defines a tangent field typically used to control anisotropic direction.

InputRotation takes a single grayscale channel where black means 0 degrees and white means 360 degrees.
InputVector takes a 2-channel map where the red channels is x and green is y. The blue channel is ignored.

The vector method often gives better results by minimizing texture filtering artifacts. If such artifacts are too visible, use the nearest texture filter.

Important

The nearest filter disables entirely mip-mapping, so you should only use it with a low-resolution map to avoid slowing down the renderer and consuming too much texture memory.

For an example of PxrTangentField in action, check out the video!

Input Parameters

Input Rotation

A single float value to rotate the shading tangent. This input will take precedence over inputVector.

RIB: float inputRotation

Default: 0.0

Input Vector

The red and green channels will be read as x and y coordinates of a 2d vector. If inputRotation is connected, this input will be ignored.

RIB: color inputVector

Default: 0.0 0.0 0.0

Rotation Offset

A global rotation offset in degrees.

RIB: float rotationOffset

Default: 0.0

Rotation Range

Scales the rotation range. 1.0 equates 0 to 360 degrees.

RIB: float rotationRange

Default: 1.0

Centered Vectors

Centers the gradient values of the vector map. Ignored when inputRotation is used.

RIB: int centeredVectors

Default: 1

Output Parameters

resultXYZ

The final tangent vector that should be connected to the Bxdf's Shading Tangent input.

Sample textures

Sample textures have a resolution of 256x256 pixels and should tile perfectly (use the appropriate txmake wrap mode, e.g. txmake -mode periodic; note that for the final release, pre-made .tex versions will be provided in the /lib/textures/ directory of your RPS installation and the /rmantree/lib/textures directory of RMS).

Texture	Description
	Rotation map to create an anisotropic brushed metal pattern.
	Vector map to create an anisotropic brushed metal pattern.
	Vector map to create an anisotropic fiber mesh pattern.
	Vector map to create an anisotropic carbon fiber mesh pattern.

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