Blue line/red line

[DerBlitzer]

Something I've noticed for a while, but can't figure out. When I target something, most often I get the usual blue line. But sometimes I get a dark red line. I'm not talking about the orange/black line that tells you about blocked LOS; I mean a red line indicating good LOS; what does it signify? Can't find anything about it in the manual.

[tankibanki]

It has got to do with troops facing the wrong way. You will get it for sneaking infantry when trying to target anything which cannot be attacked without your unit turning (and thereby contradicting your sneak command).

You also get it for units with forward mounted MGs and for assault guns.

[stoat]

It happens when your units are moving, and the point that you want them to target is outside their periphery. You get this with moving vehicles like bren gun carriers, Priests, and assault guns where they can't target anything outside the angle of traverse of their guns while they are moving. If you cancel the movement order, you should be able to target things just fine.