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editormaydefinerotationinradianswithanangle-axisVector4.However,theusermay
notknow
whatanyofthosewordsmean,andtheysimplythinkofrotationasbeingbetween0and
360degrees,onthex-,y-,andz-axes.
Foreachuserobject,wetakenoteofhowtheuserperceivesthemby
makingalistofattributesandactions:theattributesoftheobject,andtheactionsthatyou
performwiththeobject.Ifthediscussionabouttheuserobjectsturnstofeaturesrequests,
steertheconversationbacktowhattheuser’sgoalsare,andhowtheycanbetranslated
intoattributesandactions.
Oncewehaveperformedacontextualanalysiswithafewusers,we
canstarttoidentifythemostcommonattributesandactionsrequested
bymostusers.Thiswillhelpustofocusontherightfeaturesusedbythemajorityof
users.
Forexample,ifweworkedwithausertocreateauserobjectforapointlight,theresults
mightlooklikeFigure4.19.Thisuser’smentalmodelofapointlightisthatithasthe
attributesofcolor,intensity,andrange.TheyalsoconsiderthecolorasbeingsetasHSV
(hue,saturation,andvalue),theintensityasanumber(where100isequalto100percent
intensity),andtherangeismeasuredinmeters.
Object
Attributes
Actions
Pointlight
Color(HSV)
Movelight
Intensity(100=100%)
Changethecolor
Range(inmeters)
Settheintensity
Setrange
Enableordisable
FIGURE4.19Exampleofauserobjectforapointlight.
*TwopopularoptionsareOptimalSort(http://www.optimalworkshop.com/
optimalsort.htm)andWebsort(http://dirtarchitecture.wordpress.com/websort/).These
servicesalsoprovideanautomatedanalysissuchasmostcommongroupings,trends,and
soon.
Analysis◾65