The only current way to achieve smooth random currently is to use Random Sample+Hold (Source: WhiteNoise, Trigger:Clock) and explore with adjusting rise and fall. This is flawed in one way in that the curves of the rise and fall are logarithmic, which is very rarely useful as a modulator. As a starting point, I would recommend exploring traditional slew limiters and how they respond to voltage changes.
More in depth - A few modules in the eurorack world to study are the fluctuating random generators on the Frap Tools Sapèl module; the Low Frequency Vacillator function on the Intellijel Quadrax; or the unquantized output of one of the 'y' and three 'x' channels on Mutable Instruments Marbles.
All of these output completely random voltages that have the ability to completely smooth any abrupt changes to varying degrees.They are typically generated using white noise as a source.
They typically have control over rate of change; the ability to control bias - emphasizing more weight toward higher/lower/median/extents of the voltage range; and even the amount of slew (filtering) that softens the abruptness of change.
While Turing and S&H generators are nice, I feel that Smooth Random generators are key to creating more evolving and generative modulation.
I would love to see a Smooth Random generator in Pigments that has controls for Rate of change (Sample rate from the noise source), Bias (bias towards -100% or +100%) and Weighting (more weight towards +/-100% or towards 0%), and Smoothness - with 0 outputting what looks like pure white noise, and 100% smoothing/slewing/averaging voltage changes over minutes.
