.. _bpy.types.ShaderNodeTexWhiteNoise:

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White Noise Texture Node
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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/render_shader-nodes_textures_white-noise_node.png
   :align: right

   White Noise Texture Node.


Inputs
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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.


Notes
=====

The slightest difference in seed values would result in completely different outputs.
Consequently, bad precision may have significant impact on the output.
This issue mostly affects Cycles but not Eevee.
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.

.. 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.