NAME¶
al_set_mouse_wheel_precision - Allegro 5 API
SYNOPSIS¶
-
#include <allegro5/allegro.h>
void al_set_mouse_wheel_precision(int precision)
DESCRIPTION¶
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.
SEE ALSO¶
al_get_mouse_wheel_precision(3alleg5)