I have already read the UE4 Docs about BluePrints.
So then i go to watch BluePrints QuickShot.
And in the video there is a “Single Line Trace by Channel” Node.
I don’t know what it mean and what’s its feature
And I google it ,but get nothing.
So please tell me what’s it ,in depth is appreciated
Basically a line trace checks for actors in it’s path by “Colliding” with them. You then have a Hit Result which returns that actor or actors. You can then put that Hit Result into a Cast node and call functions inside that actor. So bullet shoots in a line, line trace gets actors in path, and executes your “Shot by Bullet” Event which could Destroy Actor.
The channel is something you can set per actor or actor class so that your line trace hits 1 actor but not another. I believe you can set channels in your project settings.
This has a really nice explanation of collisions and channels.
Missing a link?
The text “Collision Documentation” is the link, just click it =).
Here it is again just in case: