Procedural Mesh "painting"

Hello,
I’m still new to Procedural Mesh but I’m trying to write a function that allows me to “paint” with the mesh. I used Trigonometry to calculate and add the triangles I needed, but it was less successful.
I would be very grateful if someone could give me an idea on how to achieve my goal.

Feel free to ask for additional Information.

EDIT:
I want to create a brush with which I can edit the level in a 2D side scroller.

This should become this:

Sorry for the missing information. I’m not good at asking detailed questions, but I’m committed to learning. Does the edit help you?

What do you mean ‘paint’. You have to be more detailed with this stuff. What will the result actually look like, ad how do you draw it? Check the contentExamples map.

It does help. I haven’t worked with 2D at all. Are you sure Procedural Mesh is what you actually want? There is an example of drawing a heightmap in the Bluepirnt_RenderToTexture map, but I think you’d need to handle collision yourself. Check out spline mesh actor too.

You should post the BP you are having trouble with as well.