Dim LED lights on a specific time schedule

I am looking to dim my LED lights using my Caseta & Hub. What I want is a program that will allow me to set a virtual clock timing for say 20 minutes or 3 hours (or whatever time period I want) so that the lights go through a day/ night cycle to represent "scale" time i.e. at the half way point in the cycle the lights are maximum (noon) and then dim to the off point.

Lutron support suggested the Smart Things or LFTTT apps but in reading user comments on these software apps prior to downlead it doesn't give me a positive feeling. Ultimately I would like to have some way to write my own code to run on a Raspberry Pi or Arduino but would that ever be part of the Lutron app integration?

I haven't worked with Smart Things but IFTTT is horrible. On the other hand, if you are able to write your own version to run on Pi, you may find it tolerable.

Smart things, IFTTT, or your own code is going to be outside of the Caseta app.