MOUSE_MASK_BUTTONS
if ((m->b & MOUSE_MASK_BUTTONS) == MOUSE_WHEEL_UP)
#define MOUSE_BUTTONS(b) ((b) & MOUSE_MASK_BUTTONS)
(((b) & MOUSE_MASK_BUTTONS) == MOUSE_WHEEL_UP || \
((b) & MOUSE_MASK_BUTTONS) == MOUSE_WHEEL_DOWN)
#define MOUSE_RELEASE(b) (((b) & MOUSE_MASK_BUTTONS) == 3)