Line of Sight (EU2012)

Stub Pistol This page is currently empty or currently missing key content. Possibly due to EXALT sabotage. Please help fight the alien menace by filling this page with relevant info. Remove this stub after the page has been completed to a minimum.

While the aesthetics of the in-game fog/vision appears vague, the only requirement for having line of sight of a voxel seems to be whether a unit can see the center point of that voxel. Units are two voxels high with the center point of the top voxel being where their source of line of sight comes from. The requirement for line of sight of a unit seems to be whether there is line of sight of the top voxel of that unit. The source and destinations can be extended with the game's cover mechanic.

Estimating with the camera

Use of the in-game camera in certain cases can make quick estimates of whether two points will have line of sight of each other. If the line is clear of obstacles, there should be visibility. Unfortunately, it's not exactly easy or possible if it requires the third dimension too.

Obstacles

Most obstacles provide visual cover, even low cover. The entire cube/square acts as a blocker for vision, excluding the edges if they coincide on the line of sight.

Some non transparent obstacles seem to provide no visual cover. Not sure if it's a bug or a feature. Ramps and that one truck with a crane seem to be purely see-through. It is unclear whether these objects only provides one voxel of visual cover (like low cover) or none at all.

Transparent cover can exist, but usually only discovered through explosions. Exploded vehicles that still provide high cover may end up useless as line of sight blockers. In certain cases, an exploded wall may provide full cover due to hanging objects being intact (paintings/pictures, ladders), despite the wall behind being destroyed.

Peeking cover

Speculation. Peeking tiles do not extend the vision range, only make parts of the vision sphere centered on the unit visible. That is, what is visible is not the union of the left and right peeking tile vision spheres, it is just the vision sphere of the unit, with extra sources of line of sight clearing fog within that sphere. This is why when the unit actually steps out due to an action, they expose more vision and sometimes trigger another pod.

This can explain weird circumstances where your units get targeted by non visible units. Let's say without any obstacles, both the attacker and the target is just in vision range of each other at a diagonal. Now if you put full cover in front of both of them, but also block the closer peeking tile of the attacker, the attacker seemingly steps outside of the vision range but still has vision, while the target has no visibility of the attacker because the attacker's outer peeking tile would be out of vision range as well as the attacker's closer peeking tile and original position is blocked by vision blockers.