Hi.
Single square and líne of sight
Line of sight can be drawn to a figure occupying blocking terrain, the attacker does not need to be adjacent. You can draw line of sight (and count spaces) to the space the figure occupies, or the chosen target space if the figure is large, but you cannot draw line of sight through (both into and out of a blocking terrain space).
In effect you ignore the terrain of the target space, but you don't ignore the terrain of any other space when drawing line of sight or counting space to the target of an attack (or an ability).
See also: https://community.fantasyflightgames.com/topic/247683-counting-spaces-blocking-terrain-and-mobile/
See also the FAQ, and https://www.boardgamegeek.com/filepage/168240/consolidated-star-wars-imperial-assault-rules (Or from http://www.iki.fi/a1bert/TheConsolidatedImperialAssaultRules.pdf )
Edited by a1bert