Generates a random value using the Perlin-noise algorithm.

ret noise(x)


Item Description
[in] A floating-point vector from which to generate Perlin noise.

Return Value

The Perlin noise value within a range between -1 and 1.


Perlin noise values change smoothly from one point to another over a space, creating natural looking, randomly generated values. You can use Perlin noise to generate procedural textures for effects like smoke and fire.

Type Description

Name Template Type Component Type Size
x vector float any
ret scalar float 1

Minimum Shader Model

This function is supported in the following shader models.

Shader Model Supported
Shader Model 2 (DirectX HLSL) and higher shader models no
Shader Model 1 (DirectX HLSL) yes (tx_1_0 only)

See also

Intrinsic Functions (DirectX HLSL)