Pop-up Depth Views for Improving 3D Target Acquisition
In GI '11: Proceedings of Graphics Interface 2011. pages 41-48. 2011.
We present the design and experimental evaluation of pop-up depth views, a novel interaction technique for aiding in the placement or positioning of a 3D cursor or object. Previous work found that in a 3D placement task, a 2D mouse used with multiple orthographic views outperformed a 3D input device used with a perspective view with stereo. This was the case, even though the mouse required two clicks to complete the task instead of only the single click required with the 3D input device. We improve performance with 3D input devices with pop-up depth views, small inset views in a perspective display of the scene. These provide top- and side-views of the immediate 3D neighborhood of the cursor, thereby allowing the user to see more easily along the depth dimension, improving the user's effective depth acuity. In turn, positioning with the 3D input device is also improved. Furthermore, because the depth views are displayed near the 3D cursor, only tiny eye movements are required for the user to perceive the 3D cursor's depth with respect to nearby objects. Pop-up depth views are a kind of depth view, only displayed when the user's cursor slows down. In this manner, they do not occlude the 3D scene when the user is moving quickly. Our experimental evaluation shows that the combination of a 3D input device used with a perspective view, stereo projection, and pop-up depth views, outperforms a 2D mouse in a 3D target acquisition task, in terms of both movement time and throughput, but at the cost of a slightly higher error rate.