In this article we consider another point of view for perpendicularity, by replacing the involution at line at infinity to itself that sends an infinite point to the one with perpendicular direction, by another one: given a point $S$, we consider the involution at line at infinity that sends the infinite point of the sidelines to the infinite points of cevians of $S$.
In this way for each statement of problem that involves perpendicularity we get a new version.
