The signature idea of region codes, also called outcodes, belongs to one classic method. Around the rectangular clip window the plane is split into nine zones, and each endpoint gets a 4-bit code for the top, bottom, right, and left half-planes.
Trivial rejection happens when the bitwise AND of the two endpoint codes is non-zero, and trivial acceptance when both codes are zero. This is the Cohen-Sutherland line clipping algorithm.
Liang-Barsky is parametric, Weiler-Atherton handles polygon clipping, and midpoint subdivision repeatedly halves the segment, so none of them use outcodes.
\[\boxed{\text{Cohen-Sutherland Algorithm}}\]