I took the Dunes function (https://planetside.co.uk/forums/index.php/topic,18400.msg178752.html#msg178752) by wiwine packaged it and added some of the controls I add to my shaders. There is more I wanted to do, but I actually spent more time than I should have being a perfectionist on the example scene to view my work that I tired myself out. Lol I could NOT do the overlapping waves and had to have my scene defeat these issues. Lol.
Function settings are individually documented with a description, and I hope this helps to understand what things are doing, or their intended use.
Note: Your pre-pass will hang. This is normal. This function uses trigonometry functions, and when you're using 3 of the same function with different settings, there is a wee bit of calculation time.