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.. _bpy.types.ShaderNodeTexWhiteNoise:
************************
White Noise Texture Node
************************
The *White Noise Texture* node returns a random number based on an input :term:`Seed`.
The seed can be a number, a 2D vector, a 3D vector, or a 4D vector; depending on the *Dimensions* property.
The output number ranges between zero and one.
.. figure:: /images/node-types_ShaderNodeTexWhiteNoise.webp
:align: right
:alt: White Noise Texture Node.
Inputs
======
The inputs are dynamic, they become available if needed depending on the node properties.
Vector
Vector used as seed in 2D, 3D, and 4D dimensions.
W
Value used as seed in 1D and 4D dimensions.
Properties
==========
Dimensions
The dimensions of the space to evaluate the noise in.
:1D: The *W* input is used as seed.
:2D: The X and Y components of the *Vector* input are used as seed.
:3D: The *Vector* input is used as seed.
:4D: Both the *Vector* input and the *W* input are used as seed.
Outputs
=======
Value
Output random value.
Color
Output random color.
.. _shader-white-noise-notes:
Notes
=====
The slightest difference in seed values would result in completely different outputs.
Consequently, bad precision may have significant impact on the output.
Usually, we can mitigate this issue by:
- Eliminating the problematic seed value. If the problematic seed value is constant,
it should be eliminated by choosing a lower dimension or multiplying it by zero.
- Adding an arbitrary value to the seed. The issue might only happen at certain boundaries,
like unit boundaries, so simply adding an arbitrary value might solve the issue.
- Taking the absolute value of the seed. In computing, zero may be positive or negative,
so taking the absolute values unifies the zero into a single value.
.. list-table::
* - .. figure:: /images/render_shader-nodes_textures_white-noise_issue.png
Precision issue due to signed zeros on the Z axis.
- .. figure:: /images/render_shader-nodes_textures_white-noise_solution1.png
Mitigating the issue by eliminating the Z axis.
* - .. figure:: /images/render_shader-nodes_textures_white-noise_solution2.png
Mitigating the issue by adding an arbitrary value.
- .. figure:: /images/render_shader-nodes_textures_white-noise_solution3.png
Mitigating the issue by taking the absolute value.
Examples
========
.. figure:: /images/render_shader-nodes_textures_white-noise_solution1.png
Generating cell noise using the *Snap* vector operation and the *White Noise* node.
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