private void ChangeBrushOnMouseScroll()
{
UserInterfaceManager u = GameObject.Find("UI").GetComponent <UserInterfaceManager>();
int i = u.GetCurrentBrush();
if (Input.GetAxis("Mouse ScrollWheel") > 0)
{
u.SelectBrush(++i);
}
if (Input.GetAxis("Mouse ScrollWheel") < 0)
{
u.SelectBrush(--i);
}
}