I need explanation

[MGuard]

I know this may be a time-consuming task and I feel stupid because I'm aven asking but anyway
Can someone explain how this scene is made:

Guided Missile

flm8620

Rating:
Filesize: 15.17 kB
Comments: 2
Ratings: 2

I'm trying to something similar to this and actually managed to do with differend kind of method but it turned out to be inaccurate so I found that scene. However I don't get how it works

Specially this damn code (found from "The Radar") doesn't make sense for me

Code: Select all

(e)=>{
    scene.my.c = scene.my.b - scene.my.a;     scene.my.flm = (scene.my.c(0) * scene.my.target(0) + scene.my.c(1) * scene.my.target(1)) > 0 }

Seems to be somekind of calculation but what it calculates
I'm new to thyming and I barely know even the basics yet so if you don't mind explaing it using much details.

And oh.. another question, can I "activate" a laser by using another laser? I mean that when the laser hits an object the other laser turns on.
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Sry my native language isn't english so you probably found bunch of spelling mistakes ect.