Bullet holes in the wall?

I have a bullet, which hits the wall

Wouldn't it be nice, to leave his own signature?

Therefore I'm asking if there is some code or examples that I can use in the start, and how to realize it best

In games, the hole is a texture, that is painted on the wall. No clue how to paint a texture on the exact position.

And what to do, if it's not a simple wall? (For example a tree, or a house)

Perhaps you can use texture splatting?


I think a keyword for this is "decal".