Perlin Noise 2D
The Perlin Noise 2D modifier adds one-dimensional Perlin noise to the stroke. The modifier generates noisy displacements using 2D coordinates of stroke vertices as the input of the noise generator.
How dense the noise is (kind of a scale factor along the stroke).
How much the noise distorts the stroke in the Angle direction.
The seed of the random generator (the same seed over a stroke will always give the same result).
The «level of detail» of the noise.
In which direction the noise is applied (0.0 is fully horizontal).