Range indicator around character

Hi there,

I would like to make a range indicator around a character respectively a range indicator around a specific point.
The indicator should be projected to the surrounding geometry from above.
I tried to do this with decals but they stretch if the angle is to sharp.

You can see the effect I want to achieve here:
[video of effect][1]
Here is a picture:

You see the circle is perfectly going with the geometry and there is no stretching or something like this.

I would be grateful for any help.

Best wishes,

Henning