GroupDesign [,], another locking-based collaborative drawing tool, provides a less jerky interface for committing a series of changes to remote users. When an operation is initiated on an object, an icon is displayed in the object to other users indicating that the object is being manipulated. The shape of the icon indicates the kind of operation being executed and the colour identifies the initiator. When the operation completes, animation is used to explain to others the result of the operation. GroupDesign also provides a more intelligent locking protocol that allows users to execute operations on locked objects that are compatible with the operation that locked it. For instance, it allows simultaneous execution of rotate and colour operations on a rectangle.
As in GroupDraw, each user can scroll to a different part of the drawing and place his window at a different location. A user's action on an object is is echoed
audibly to those who have scrolled the object away by identifying the kind of the operation performed on it.
GroupDesign provides two special modes to allows users to synchronize views that have been scrolled to different parts. In the Localize mode, a user is ``teleported'' to the views of one or more users, from which he can return to his view. In the Teleconference mode, users views are linked so that they see each others scrolling and window changes. The pointers are not shared in this mode, but a GroupDesign object can be used as a telepointer.
It provides two other useful modes to support awareness. In the Identification mode, it displays every object with the colour of the person who last modified it. In the age mode, it uses colour to indicate the age of the object. Finally, in the Time Relaxed mode, users actions are not seen by others until they explicitly commit them. Users can also offline play the history backwards or forwards.