Well they are two alpha (not additively) blended quads arranged 90 deg to each other in a + fashion that have repeating textures in the y direction adjusted with texture coords. It was slightly tricky to make since the beam needs to stay the same but become shorter if it hits anything, so I have to modify the texture coords according to the beam’s length.
Finally I wrote a very simple shader that moves the texture along the y axis as fast as it can look.
The texture I made for it:
Oh and the gif is running at a slightly reduced speed so the beam moves even faster at 60fps.
Btw, this was my inspiration:
Everspace in UE4, reminding me how good my game won’t ever look…