Hook functions used by the gui routines to access the mouse state. allegro game programming library.
#include <allegro.h>
extern int (*gui_mouse_x)();
extern int (*gui_mouse_y)();
extern int (*gui_mouse_z)();
extern int (*gui_mouse_b)();
Hook functions, used by the GUI routines whenever they need to access the mouse state. By default these just return copies of the mouse_x, mouse_y, mouse_z, and mouse_b variables, but they could be used to offset or scale the mouse position, or read input from a different source entirely.