While Peter Hutterer has been involved with the X.Org Server’s input code and related projects for the past decade now and has spearheaded the projects around Multi Pointer X, X Input 2, and the Wayland/Xorg-using Libinput libraries, he’s still had a tough time grasping the X.Org Server’s pointer acceleration code…

Source: Phoronix – Understanding The X.Org Server’s Complex Pointer Acceleration Code