1. high-density cursor helps users keep track of fast-moving mouse cursors
patrick baudisch
edward cutrell, george robertson
microsoft research
visualization and interaction research

2. contents problem users lose track of cursor
high-density cursor is not a mouse trail
related work
design and more design
user study hd-cursor makes users faster
conclusions

3. goals
with today’s large screens and multimon users lose track of the cursor
high-density cursor solves this problem by filling in additional cursor images
high-density cursor makes users faster while having virtually no side-effects
general insight: display frame rate is not a hard limit

4. large screens and multimon
information mural [Guimbretière, Winograd]
on large screens optical flow helps navigation [Tan 2001]
large screens help productivity tasks [Czerwinski 2003]
focus-plus-context screens faster than overviews [Baudisch 2001]
multi-monitor setups: access palette windows in Photoshop, CAD… [Grudin 2001]
No Multimon
30%
Plan to Use
Multimon
38%
Use Multimon
32%
[Jon Peddie Research Dec, 2002 N=6652]

5. challenge: keeping the mouse working
longer distances à higher mouse acceleration
temporal aliasing: 500 pixels jumps
lack of visual continuity à users lose track of the cursor

6. the problem will get worse
“yes, but won’t faster computers make this problem go away?”
à NO: cursor update is limited by screen refresh rate
screen refresh rate has actually decreased (LCDs)
larger screens + lower refresh rate à status quo
future: even larger screens à problem will get worse

7. demo… inserts cursor image between actual cursor positions
previous cursor position
inserts cursor image between actual cursor positions
 the mouse cursor appear more continuous
current cursor position
fill-in cursors current frame
fill-in cursors previous frame
mouse
motion

8. this is not the mouse trail
 video
the windows mouse trail…
makes mouse trail last longer
drawback: cursor images lag behind
...is not high-density cursor
hd cursor makes mouse trail denser
lag-free: mouse stops => cursor stops

9. benefits 1. mouse cursor appear more continuous
previous cursor position
current cursor position
mouse
motion
fill-in cursors current frame
mouse
motion
fill-in cursors previous frame
1. mouse cursor appear more continuous
à easier to track the cursor
2. higher “visual weight”
à easier to re-acquire the cursor

10. related work acquiring distant targets
move cursor with eye gaze (Sibert and Jacob, 2000), Magic pointing (Zhai et al., 1999)
flick snaps cursor to target (Dulberg et al. (1999)
sticky icons capture cursor (Swaminathan and Sato, 1997)
throwing gets across long distances (Geißler, 1998)
expanding targets save space on screen (McGuffin and Balakrishnan, 2002)
drag-and-pop (baudisch et al 2003)
enhance detectability of the mouse cursor
<ctrl> for radar animation (Microsoft, Steve Bathiche)
cursor growth (Kensington Mouseworks 2001)
mouse trail for slow response LCDs (e.g. MS Windows)
liveCursor points in the direction of its motion (Ben Bederson)
motion blur and temporal supersampling
reduce temporal aliasing, such as stroboscope, e.g. wheel spokes
rendering a scene multiple times (Dachille and Kaufman, 2000)
improve the perceived responsiveness of graphics apps (Conner and Holden, 1997)
help users anticipate motion (Chang, 1993; Thomas & Calder, 2001)

11. design

12. design goals
for users who track the cursor enhance the predictability of the cursor path
enhanced trail density/continuous blur
smooth interpolation of the cursor path
preservation of trail density as a cue for cursor speed.
for users who reacquire the cursor increase the detectability of the cursor (visual weight)
enhanced trail density
enhanced cursor opacity
and cursor scaling.
preserve responsiveness

13. designs alternatives reference: exponential acceleration a b c d e f gh
frame
acceleration
reference: exponential acceleration

14. designs alternatives motion blur with higher weight a b c d e f g h
frame
acceleration
motion blur with higher weight

15. designs alternatives temporal super-sampling vs. motion blurc d
chose discreet version
1. latest cursor position is always shown blur-free and in full opacity
2. appearance that users are familiar with today
3. computationally less expensive e f g h
frame
acceleration
temporal super-sampling vs. motion blur

16. designs alternatives density = detectability vs. intrusiveness a b c df c h g
frame
acceleration
density = detectability vs. intrusiveness

17. designs alternatives a b d e f c h g
frame
acceleration
distance between cursor images as cue for mouse speed

18. designs alternatives smooth interpolation a b c d e f g h frame
acceleration
smooth interpolation

19. transfer function distance between cursor images
hd cursor has no effect
transfer function (configurable)
cursor trail provides no speed cues
onset threshold
(configurable)
mouse speed

20. designs alternatives optional cursor growth a b c d e f g h frame
acceleration
optional cursor growth

21. bezier interpolation cursor position 1. linear interpolation
2. attraction point
3. interpolate
cursor position
1. linear interpolation

22. user study

23. pre-study goal: define interfaces for user study
participants: 14 coworkers
informal procedure
try out high-density cursor
try out different settings (density, onset…)
choose “favorite” setting
resulting interface parameters
12-17 pixels/frame vs. 35 pixels/frame
distance = sqrt(n)
cursor growth on or off

24. user study hypotheses high-density cursor faster
interfaces: control vs. high-density cursor (conservative, tripleDensity, plusScaling)
fitts’ law task
triple-mon: button located at 5” to 40” distance
participants: 7 external participants, 5 coworkers
hypotheses
high-density cursor faster
the greater the distance the greater the effect
tripleDensity and plusScaling faster than conservative

25. time % relative to regular cursor
results
regular mouse cursor 90 92 94 96 98
100
102
short distance
speedup up to 7%
conservative
+ scale
+3-dense
time % relative to regular cursor
high-density cursors
125
250
500
750
1000
target distance (mm)

26. subjective satisfaction
Condition
Liked Most
Liked Least
control 7
HD_conservative 2 3
HD_tripleDensity
HD_plusScaling 6
most participants did not notice that cursor was different! “did that condition use a different mouse acceleration?”…

27. goals revisited - conclusions
with today’s large screens and multimon users lose track of the cursor
high-density cursor solves this problem by filling in additional cursor images
high-density cursor makes users faster while having virtually no side-effects
general insight: display frame rate is not a hard limit

28. thank you! try it out: Google high-density cursor
more about motion blur and animation drag-and-pop talk tomorrow 4:30pm
thanks to: eric horvitz, dan robbins brian meyers, pravin santiago steve bathiche, colin anthony john pruitt, mary czerwinski greg smith, and desney tan
paid advertisement

29. (a) mouse trail t
mouse
motion
(b) high-density cursor t
mouse
motion