OmniGraph Node omni.graph.nodes.Noise

omni.graph.nodes.Noise Properties

Name

Value

Version

1

Extension

omni.graph.nodes

Has State?

False

Implementation Language

C++

Default Memory Type

cpu

Generated Code Exclusions

None

uiName

Noise

__categories

math:operator

Generated Class Name

OgnNoiseDatabase

Python Module

omni.graph.nodes

omni.graph.nodes.Noise Description

Sample values from a Perlin noise field.

The noise field for any given seed is static: the same input position will always give the same result. This is useful in many areas, such as texturing and animation, where repeatability is essential. If you want a result that varies then you will need to vary either the position or the seed. For example, connecting the ‘frame’ output of an OnTick node to position will provide a noise result which varies from frame to frame. Perlin noise is locally smooth, meaning that small changes in the sample position will produce small changes in the resulting noise. Varying the seed value will produce a more chaotic result. Another characteristic of Perlin noise is that it is zero at the corners of each cell in the field. In practical terms this means that integral positions, such as 5.0 in a one-dimensional field or (3.0, -1.0) in a two-dimensional field, will return a result of 0.0. Thus, if the source of your sample positions provides only integral values then all of your results will be zero. To avoid this try offsetting your position values by a fractional amount, such as 0.5.

omni.graph.nodes.Noise Inputs

Name

Type

Default

Required?

Descripton

inputs:position

[‘float’, ‘float[2]’, ‘float[2][]’, ‘float[3]’, ‘float[3][]’, ‘float[4]’, ‘float[4][]’, ‘float[]’]

None

Y

Position(s) within the noise field to be sampled. For a given seed, the same position will always return the same noise value.

inputs:seed

uint

0

Y

Seed for generating the noise field.

__default

0

omni.graph.nodes.Noise Outputs

Name

Type

Default

Required?

Descripton

outputs:result

[‘float’, ‘float[]’]

None

Y

Value at the selected position(s) in the noise field.