Techniques for Interacting with Off-Screen Content

Pourang Irani Carl GutwinUniversity of Manitoba University of Saskatchewan

Grant Partridge Mahtab NezhadaslUniversity of Manitoba University of Manitoba

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Introduction

2D navigation: Time Multiplexing

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Zooming

2D navigation: Space Multiplexing

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Overview+Detail DragMag

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Proxy-based techniques

[Baudisch et al., 2003] [Bezerianos and Balakrishnan, 2005]

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2D navigation: Proxy

Hop (Halo + Proxies)

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Tasks

• Baudisch & Rosenholtz [2003]

– “Position”– “Closest”– “Avoid”

• Spatially Absolute– Existence, Count, Location

• Spatially Relative – Proximity to reference, Proximity b/w objects, Cluster

Evaluation: Conditions

• Navigation Techniques– Zoom - two-level zoom– DragMag – Hop

• Tasks– Absolute– Relative

Zooming

DragMag

Hop

Results: Completion Time

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Existence ObjectCount

Location ProximitybetweenObjects

Proximityfrom

Reference

Cluster

Spatially Absolute Tasks Spatially Relative Tasks

HopDragMagZoom

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Existence ObjectCount

Location ProximitybetweenObjects

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Cluster

Spatially Absolute Tasks Spatially Relative Tasks

HopDragMagZoom

HopDragMagZoom

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Possible explanations – strategy

• Number of operations about 1/5 with hop

• Zooming requires more “trips” …– not so good for absolute tasks

• … but good for spatial information– useful for relative tasks

• DragMag reduced the number of “trips”– allows users to perform relative tasks with ease– but added complexity of managing windows

Possible explanations – task-based• Relative tasks

– Need orientation and comparisons b/w views– Rely on VSTM

• Absolute tasks– Require information about the objects– Do not require spatial/orientation information

WinHop (hop + windows)

WinHop

WinHop

WinHop

WinHop

WinHop

WinHop (video)

MultiscaleZoom

MultiscaleZoom

MultiscaleZoom (video)

Absolute: Location (winhop)

Relative: Cluster (msz)

Results

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Existence

Multiscale-ZoomWinHopHopDragMagZoom

Spatially Absolute Tasks Spatially Relative Tasks

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ObjectCount

Location ProximitybetweenObjects

Proximityfrom

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Cluster0

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Existence

Multiscale-ZoomWinHopHopDragMagZoom

Multiscale-ZoomWinHopHopDragMagZoom

Spatially Absolute Tasks Spatially Relative Tasks

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ObjectCount

Location ProximitybetweenObjects

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Cluster

Limitations of Hybrid Techniques

• WinHop– Many operations, significant learning curve

• MultiScale Zoom– Clutter from proxies

Main Findings

• Each task requires a different navigation strategy

• Proxy-based ideal for target-only info tasks

• Time/Space multiplexing ideal for target-target info

• Hybrids improve performance in both types of tasks

• Performance with Multiscale Zoom remained constant

Conclusion

• Beneficial to investigate techniques on multiple tasks

• Ideal technique gives target and context information

• Hybrid techniques are reliably good– Consider multiscale zoom for small displays

• Hybrids performance on other tasks