Generally use gesture recognition to interpret user's actions Physical Control Real buttons, switches, etc. May require a trigger event to select, or may require a trigger event to manipulate, or the contact itself may trigger an event. Feedback is good. May be provided visually, aurally, hapticly.
Selection is generated when the cursor comes in contact with an object.
Manipulation Once we've selected an object, we may want to manipulate it. Exerting force on a virtual object Using a world model with physics Pushing, pulling, supporting, hitting objects, etc. Moving objects is done by pushing them, or picking them up and setting them down. The changed value of the virtual control may then be used to select, modify or steer some other object in the world. Example operations include adjusting the overall volume of the world, adjusting the time of day and therefore the ambient light in the world.