Hello everyone,
Ben in this section’s episode asked “Why does the vector look like a square” [From the players point of view].
I think it’s because the float we used for thickness (10.f) makes the vector 10 centimeters high and 10 centimeters wide, which would create a square shape. That is my simple answer. 
Code Reference:
DrawDebugLine(
GetWorld(),
PlayerViewPointLocation,
LineTraceEnd,
FColor(255, 0, 0),
false,
0.f,
0.f,
10.f // this is what I’m referring to.
);