1. A machine comprising: a lid operable to cover an object to be processed by the machine, the lid being touch-sensitive and enabling a user to see the object, wherein the lid includes an image sensor that is capable of capturing an image of the object and displaying the captured image on the lid for the user to review; a plate located below the lid for receiving the object, wherein the plate includes a container that is capable of receiving three-dimensional objects to enable the machine to scan the received three-dimensional objects; a scan head located below the lid and the plate, and operable to scan the object; a processing unit capable of performing a method comprising: detecting a touch input that draws a pattern on the lid; in response to detecting the touch input on the lid, identifying a part of the object based on the pattern; and controlling the scan head to generate a processing result that only contains the identified part of the object.