We explore a range of techniques that use two hands to control two independent cursors to perform operations in 3D desktop applications. Based on research results in 2D applications, we believe that two-handed input provides the potential for creating more efficient and more fluid interfaces, especially for tasks that are context-sensitive or that have many degrees of freedom. These tasks appear frequently in 3D applications and are commonly broken down into a series of sequential operations, each controlling fewer degrees of freedom -- even though this may dramatically change the character of the task. However, two-handed interaction, in theory, makes it possible to perform the same tasks using half the number of sequential steps since two previously sequential operations can be performed simultaneously. In addition, many forms of two-handed interaction may be simpler to use and to understand since they correspond to common interactions in the physical world. It is significant when ta...

IRIS@ InventorTM is an object-oriented toolkit for developers of applications that incorporate interactive, threedimensional graphics.Encapsulation of data and methods in high-level graphical objects allows Inventor to provide a significant improvement in usability to developers, as compared to the standard, low-level set of graphics primitives provided in most other graphics libraries.Inventor's object-oriented framework also facilitates extensions, which are necessary in the diverse and rapidly changing field of 3D graphics.

This paper presents an object-oriented toolkit for developers of interactive 3D graphics applications.The primary goal of the toolkit is (o make it easier for programmers to create 3D graphics applications that employ direct manipulation techniques in addition to conventional 2D-widgets.Such techniques have generally been ignored in previous graphics packages and systems.The toolkit provides a general and extensible framework for representing 3D scenes so that applications can integrate their data with graphical objects rather than having duplicate copies.A simple, integrated event model that enables direct interaction with 3D objects is also included.