Debates:Overview+Detail vs. Focus+Context

2-D vs. 3-D

cs5984: Information Visualization

Chris North

Overview+Detail vs. Focus+Context

Today• Hornbaek, “Fisheye vs. Overview+Detail”, web

» Luhui, Shumei

2-D vs. 3-D

Multi-Dimensional data• Variety of studies:

• Merwin, Wickens, Boyle, Boyer, Hollands, Barfield

• data plots, air traffic control, …

• E.g: 2 2D views vs. 1 3D view vs. 2D+color

Results

• Hard to make sense of it all…

• In general:• 2D: better accuracy, efficiency

• 3D: better overview, trends

• Architects know this!• Orthographic 3d for overview

• Plan, profile, section (?) for exact measurements

Ware et al.• Node+link graph structures in 3D space• 4 versions:

• Static 2D = 3D graph projected onto 2D, static

• Stereo 3D

• Rotation 3D (head-coupled)

• Stereo+Rotation 3D

• Task: path finding• Exist path of length 2 between 2 highlighted nodes?

Results• Error rates different, Response times same

• Static 2D worst

• Stereo 3D: 1.6x better

• Rotation 3D: 2.2x better

• Stereo+Rot: 3.0x better

• Method of rotation not important

So…?

• Static 3D beat static 2D• 3D good for revealing complex structure?

• Better to see things that are 3D in 3D! (Hubona)

• 2D = 3D - stereo - rotation• Of course it’s the worst!

• What about 2D interaction, alternative layouts?• Springs, aggregation, focal nodes, hierarchization,…

Modjeska

• Hierarchical data in VR

• 2 UIs:• 3D fly through (6 dof, VRML) similar to SGI FSN

• 2D map-view (top view of VR) with zoom/pan like Pad++

Results

• Number of search targets found:• 3D: 11.0

• 2D: 13.6 (sig)

• 3D navigation cumbersome

• 3D version is basically 2D!

Carr et al.• 3D visualizations for

Hierarchical data:• Landscape: like 3D in Modjeska

• InfoCube: 3D containment, boxes in boxes, transparency

• CamTree: like ConeTree

• VRML 6 dof navigation only

• Tasks:• Search

• Count

• Compare

Results

• 3 Tasks: Search, Count, Compare

• Best to worst (perf time & errors):• Landscape

• CamTree

• InfoCube

• Landscape: users used as 2D!• Bird’s eye, then zoom in

So…?

• 3D (6 dof) navigation cumbersome

• Custom interaction techniques more important• When doing 3D Vis, don’t just do 6 dof VR

• E.g. ConeTree directory rotations, pruning, DQ, etc.

• VR can beat PR! (Physical Reality)

• Need overview map for 3D • Disorientation problem

• e.g. Harmony web browser

Conflicting Results?

• Design of 3D navigation controls• Head tracking (natural) vs. control panel (unnatural)

• “Look at” vs. “Be in”• Fish-tank VR vs. Immersive VR

• Fish-tank: 2 dof, never lost, easier

• Immersive: 6 dof, disorientation, harder

• Multi-D vs. Graph vs. Tree• Tree can be done well in 2D

Summary

• Interaction design more important than 2D/3D• Can make good displays in 2D or 3D

• Interaction makes or breaks

• Currently: 2D interaction designs more advanced» Fisheye, F+C, O+D, zoom/pan,…

• Fish-tank 3D: • Promising results for visualizing complex structure

• E.g: Networks, biology molecules

To Do

• Compare good 2D Vis. to good 3D Vis.• E.g: HyperbolicTree vs. ConeTree

• Theory• Cost structure of information access (Card et al.)

• Calculate clicks/time to access info

• What about Immersive VR?

• Tool builders + evaluators• Builders don’t test their good tools

• Evaluators do good tests on lame tools

Assignment

• Tues: fun stuff

• Project presentations, paper

Project Presentations• Dynamic Data Visualization

» Umer, Dilshad, Satyajit

• Multi-Dimensional Parameter Space Visualization » Ravi, Prasuna, Ashwini, Vijay

• Web Snap» Sanjini, Joy, Aarthi

• Data Structure Visualization Evaluation» Priya, Gowri, Fanye, Aejaaz

• Data Structure Visualization Tool» Sumithra, Luhui, Shumei (and Matt, Sam)

• Biotech Visualization» Margaret, Josh, Matt, Yuying

• Chat Log Visualization » Marcus, Marty, Purvi

• Menu Visualization» Chris

• Data Density and Distraction Evaluation» Maulik, Ajay, Denzil

Thursday,April 26

Tuesday,May 1