Using a fill layer, you can now generate a simplex gradient noise texture. This noise can be looped seamlessly, distorted in two dimensions, and given a string of text to use as an optional custom seed value.
This new generator plugin makes use of a C port of Kurt Spencer's permissive, open source, and patent-free OpenSimplex noise implementation.
If no custom seed string is given, a seed number will be chosen randomly.
In order to achieve seamless looping without distortion we generate noise in 4-dimensions, and sample each pixel from a toroidal (doughnut-shaped) pattern. In order to keep the look of the noise consistent between looping and non-looping modes, both are sampled from 4-dimensions. (This doughnut-shape in a cloud of noise is a bit easier to imagine in 3-dimensions, but creates obvious distortion issues, and so a fourth dimension is necessary.)
Patch by Eoin and Emmet O'Neill.