al_set_mouse_wheel_precision(3alleg5) | al_set_mouse_wheel_precision(3alleg5) |
al_set_mouse_wheel_precision - Allegro 5 API
#include <allegro5/allegro.h> void al_set_mouse_wheel_precision(int precision)
Sets the precision of the mouse wheel (the z and w coordinates). This precision manifests itself as a multiplier on the dz and dw fields in mouse events. It also affects the z and w fields of events and ALLEGRO_MOUSE_STATE(3alleg5), but not in a simple way if you alter the precision often, so it is suggested to reset those axes to 0 when you change precision. Setting this to a high value allows you to detect small changes in those two axes for some high precision mice. A flexible way of using this precision is to set it to a high value (120 is likely sufficient for most, if not all, mice) and use a floating point dz and dw like so:
al_set_mouse_wheel_precision(120); ALLEGRO_EVENT event; al_wait_for_event(event_queue, &event); if (event.type == ALLEGRO_EVENT_MOUSE_AXES) { double dz = (double)event.mouse.dz / al_get_mouse_wheel_precision(); /* Use dz in some way... */ }
Precision is set to 1 by default. It is impossible to set it to a lower precision than that.
5.1.10
Allegro reference manual |