modifyVelocity :: (GLvector3 -> GLvector3) -> Entity -> Entity
modifyVelocity f t = t{velocity = f (velocity t)}
modifyVelocity :: (GLvector3 -> GLvector3) -> Entity -> Entity
modifyVelocity f t = t{velocity = f (velocity t)}
modifyVelocity f t = t{velocity = f (velocity t)}