distance from object

[Thejazzshadow]

So I made a creek/river going through a forest by using a painted shader. Now I am placing some grass in the scene and want it to be everywhere but in and right around the river. I know how to make it so the grass doesn't go in the river but I don't know how to expand the painted shader so that the grass will stop before it reaches what will be the river bank without using another painted shader. Any ideas?

[Tangled-Universe]

Duplicate paint shader and add some extra strokes to make it bigger?

[Dune]

Add a color adjust shader to the painted shader and adjust the sliders so the white area changes (smaller, larger, within the fading sides). You can test what it does by adding a surface layer at the end of the line with a testcolor, and the color adjust as its blending shader.