Help, a laser for a tracer.

hello, the title says pretty much everything.

I want to make a tracer that is a laser. kind of like a long zap. not really like a continuous laser. just one that travels through the air thats like 2-10 feet long or so, ‘a customizable length’.

and get the position where the trace starts and ends

hey, i did it a different way, *the reason it took so long is because i was just trying to figure it out myself for the most part rather than having someone walk me through it, and im 90% done. it makes the type of tracer i want and the length etc. everything is perfect, except its not getting the right material. the tracer is a purple and black checkerboard.
the line im using is


and for some reason its not picking that material for the tracer.

ive tried just doing


and that didnt work either, so i dont really know whats going wrong.

[editline]3rd September 2017[/editline]

and also, the lines/directory’s are correct. they are spelled correctly and lead the right way, i just dont know whats going wrong.

[editline]3rd September 2017[/editline]

actually i just created a folder and put them inside of it and now it works.

You might find this thread useful, if you didn’t see it already:

i looked at it a long time ago, but didnt really read through it or pay much attention.
this was when i first wanted to make a laser-like tracer
this was just another one of my projects i put off, and i finally got back to it and finished it.