2 D cs 5984 Information Visualization Chris North

2 -D cs 5984: Information Visualization Chris North

Powers of 10

Quiz • What is the “keyhole problem”? • • 4 strategies to solve the keyhole problem for 1 D? • • f+c Detail only Zoom O+d

Information Types • • Multi-dimensional: databases, … 1 D: timelines, … 2 D: maps, … 3 D: volumes, … Hierarchies/Trees: directories, … Networks/Graphs: web, … Document collections: digital libraries, …

2 -D • • • Image browsing Maps Photos 2 d funcs A powerpiont slide

2 -D: large spaces • http: //terraserver. homeadvisor. msn. com/image. asp? S=10&T=1&X=2689&Y=20639&Z=17&W=2

Tasks? • • • Search for target Patterns Distance Aesthetics Routefinding

Detail Only • Typical image browser MS Photo. Editor • Typical map browser mapquest. com

Zooming: Pad++ • Infinitely zoomable surface • Layout information in 2 d+scale • Interaction: pan+zoom • Need more info? Just zoom in! • Jazz (Bederson et al. )

Pad++ examples • Authored spaces (user specified layouts) • E. g: filesystem replacement? , presentations, stories • Hi. Note, Kidpad • http: //www. cs. umd. edu/hcil/jazz/play/ • http: //vtopus. cs. vt. edu/~north/infoviz/hinoteapplet. html • Counterpoint: powerpoint with zooming • http: //www. cs. umd. edu/hcil/counterpoint/

Pad++ examples • Automated layouts • E. g: File system, web history

Pad++ examples • In visualization

Space-Scale

Pad++ on edge Info surface • Like ray-tracing zoom window

Semantic Zooming • Zooming in, red object turns to blue label

Good/Bad • Good: • • “step back” to get overview “step forward” for more details Infinite space for more details Visual scale conceptual scale • Bad: • get lost because of no overview • Need work on input device

Overview+Detail Overview: Detail: Square in overview coupled to scroll bars of detail • Zoom factor = 6

Multiple levels = large scale overview intermediate view detail view • Zoom factor = 10*10*10=1000

Multiple Foci

Multiple Overviews • Can have different data types in each view Color slice Ca. T scan

O+D vs Detail-Only • Beard & Walker: 2 D • Chimera: trees • North: 1 D (lists) • Scrollbars are bad!

Intermediate views? • Plaisant, “When an Intermediate view matters” • abhi, sandeep Overview ? Detail view

Translucency • Lieberman, “Macroscope: Powers of Ten Thousand” • anusha, mrinmayee

2 -D + Attributes • Dynamaps: dynamic queries on maps

Assignment • Thurs: 2 -D, focus+context • Robertson, “Document Lens” » priya, parool • Leung, “Bifocal displays” » alex, qiang • Homework #2 due thurs

Next Week • tues: Visual Overview Strategies • Stasko, “Information Mural” » ben, ahmed • Rayson, “Aggregate Towers” » anil, supriya • thurs: Multiple View Strategies • Chi, “Visualization Spreadsheet” » mudita, abhi • North, “Snap-Together Visualization” » varun, kumarl