According to *Mishnah Berurah* ([OC 131:13](http://hebrewbooks.org/pdfpager.aspx?req=49624&st=&pgnum=23), and quoted in [this answer](https://judaism.stackexchange.com/a/93472/9643)), if one is outside the *shul*, but the door to the *shul* is open, and from his location he can see the place of the *Aron*, he should do *nefilat apayim*.

What if only one of these criteria are met? For example, the *shul* is L-shaped, and he's in the corner of the L where the *Aron* isn't visible to him, or he's in the courtyard of the *shul* and the door to the shul is closed, but the door is made of a glass pane through which one can see the *Aron* (or if he can see it through a window which is closed with a glass pane). Would the fact that he's still in the same room, or that he can still see it (albeit through glass) be sufficient to require him to do *nefilat apayim*?