Perspective in Egyptian art was special. For us, perspective is the representation on a flat surface of reality how it is seen by human eye. That means that observer is an important element when the artists paints or draw something.
In Egyptian art the artists had to represent reality, not how it was seen, but how it was. The Egyptian artisan did not think about depth or vanishing point when drawing, because ancient Egyptian art was not made for being contemplated, but it had a religious purpose.
However in some moment Egyptian art kept in mind the observer’s concept. When the anthropoid coffin appeared in Ancient Egypt, a new surface, with a new shape had to be decorated. This new object offered to the Egyptian artist different spaces for the iconography in the same object.