texturing terrain in-game

Scene & World Building Terrain
1

Hi

I would like to know how i could texture a precise location of a terrain Game object

And I would like to know if I am not going with by using Setpixels function and then renderer.material

The main idea is to, by clicking on a point on the terrain in-game, texture this point and only this point.

2

That will work by not using the terrain texture at all but by using a blob projector or a real decal system.

the precision of the terrain blending and its consequences would likely be very undesired.