al_get_mouse_state_axis
int al_get_mouse_state_axis(const ALLEGRO_MOUSE_STATE *state, int axis)
Extract the mouse axis value from the saved state. The axes are numbered from 0, in this order: x-axis, y-axis, z-axis, w-axis.
See also: ALLEGRO_MOUSE_STATE, al_get_mouse_state, al_mouse_button_down
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