My function was exactly the same as yours. The only difference was that I didnt have the '-0.8' in the projected texture map.
I guess I should have gone to sleep too - I understand it better now. I only made changes in the branch that defines the ratio in the blender node, or made changes in the texture map node, but not both together in a correlated manner. Seems so obvious now:)
I can get similar results to yours now -hurray. I'm pretty sure my previous method, defining the position and using the subtract node would work too if I move the texture map at the same time.
I might prefer that because then I could position primitive objects where I want my features to be, read their position in the world browser and enter the numbers in this function. Seems more straightforwards than measuring a distance. Depends on the circumstances of course.

Also, it will look a lot cleaner if I dont  have to define two numbers -one in the multiply and one in the texture map. These numbers are related, and I shouldnt be able to define them independently. I remember now -but I wont in a few days.
But this is a detail, the method works for multiple features - that's so cool!

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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