CONE TREES: ANIMATED 3D VISUALIZATIONS
OF HIERARCHICAL INFORMATION
George
G. Robertson,
Jock
Xerox
Palo
3333
D.
A4ctckinlay,
Alto
Research
Coyote
Palo
Alto,
415-494-4755,
Hill
CA
ancl Stuart
Road
94304
rol)ertso]l.j)a,rc@
xerox.
colll
ABSTRACT
ing technologies
inlation
cognition”
tasks,
technologies
information
can
iion
offer
3D visualization
potential
solutions
when
the
structure
ized.
We
describe
iion techniques,
visualizing
erarchy
of
screen
whole
structure.
sonle
of the
tual
the
Tree,
enable
cognitive
be
gous
to Scientific
SenlNet
visual-
load
is used
for
The
The
hi-
ploitation
effective
visualization
to the
these
when
be visualized
an-
“large
scale
structure
thus
Information
techniques
interactive
these
the
ancl
of the
exploitecl.
We
V2suakzation,
analo-
Visualization.
[2-?]system
is an
early
of 3D visualization
use of
The
of the
l;llolvledge
structures
and
(,o shift
~esult,s
human
percep-
understanding
tended
in SenlNet
\Yt=re oftjeu
to be cluttered,
the
exanlple
of’ the
of infornlation
visualized
bases,
is used
In this
visual output strategies,
inierjace
metaphors,
graphic presentahlethods:
analysis of contions, screen layout. Analysis
Domain
Specific
Designs:
tenis of particular
domains.
inforntaiion
retrieval.
User-Interface
Design
Issues:
paper,
were
the
mostly
largr
graphs,
cognitive
!vas still
ex-
structut’es,
arl]itfrary
and
structure
structures
archies
are
quite
tures
to
Visualization
allows
of intellectually
exploiting
tion
the
and
hunlan
in the
we
deal
with
Infornlation
access
infortnation
spaces,
is there
and
how
systeill,
an
lnanagenlent
because
the
at
the
various
parts
3D
The
lask
of
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using
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Permission
to
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title
of the
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copying
Machinery.
and/or
01991
without
fse
of
exists
Our
infor-
tures,
and its date
is by permission
To copy
otherwise,
of this
specific
permission.
ACM 0-89791-383-3/91
of the Association
or to republish,
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aid
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for
advantage,
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publication
cases,
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recognition
volume
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and
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sense
set of problenls
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utility
than
ubiquitous,
exploit.
It, does so by
cognitive
A sinlilar
world,
to
collections,
to stinlulate
data.
information
mation
scientists
data
perceptual
visualization
of patterns
the
large
almost
be transforxnecl
hanced.
on visualizing
rather
applications,
so the
Scientific
we focus
nmtion
ferent
INTRODUCTION
in
especially
to
system,
KEYWORDS:
out
and
solutions
Visualtza-
which
aninlation
potential
call
structures.
to nlaxilnize
and
Interactive
user’s
can
for 3D visualization
ofler
especially
Information
Cone
in 3D
aninla-
problenl,
information
space
interactive
information
of these
called
is presented
to this
the
one
hierarchical
available
and
Card
(lenter
The task of managing
and accessing large information
Enwrging
spaces is a problem in large scale cognition.
for
K.
fralll
is
.4rc/)21ect7~7e[ 10],
asynchronolls
animation.
navigation[7,
for
F\YOL’li
6] and
1t
in-
object
manipulation[7],
Interucttue
visualizers,
and
3D
Objects
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for
for
building
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to
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information
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to learn
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substructure
The
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display
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or
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familiar
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systems
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in the
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supports
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or~-
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tions
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path,
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to be willing
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CONE TREES: BASIC APPROACH
laid out uniformly
Cone Trees are hierarchies
dimensions.
is presented
by fold-
are visualized
a malleable
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three
structures,
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Figure
1: Aspect
Ratio
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and
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3D Trees.
the
aspect
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that
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independent
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on the
displayed
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number
of levels
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USER PERCEPTIONS
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nocle
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to help
continue
statts,
subliminally.
191
the
target
earlier,
rooted
by highgrasped
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ill another
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parameters
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in [6] are med
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change
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to
techniques
described
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erty sheet.
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techniques
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it easier
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interest
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of trees,
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of interest
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to highlight
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viewer.
closer,
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perception
ber
tion
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of
of the
relationships
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tures
of
view
a degree
view
and simulated
a fisheye
effectiveness
view[4]
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on
and grow
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perspective
describe
of the
mentioned,
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3D
fisheye
is brighter,
selection
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to
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cause of coloring
reported
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a fisheye
having
as in
already
enhance
example,
provides
without
function,
effects
completely.
rotations
properties
the tree,
to perceptual
more
structure
making
of nodes,
(until
is reached).
In addition
the
MANIPULATION,
look
structure
it
helps
addition,
be pe~formed
allow
number
(about
it
provicle
we describe
and
of levels
brings
In
technique
perceptual
also
It
life,
This
GARDENING,
0,00
by ex-
to
into
into
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load
system.
information
which
effect,
information
insights
structures.
40.00
the
continuous
gains
perceptuzd
of cognitive
perceptual
ancl
understand
COIMTW:
reduction
human
interface
tasks
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indicator
and
visible.
whose
size indicates
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5 shows
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node
of the
the
node
a red
score.
file
name.
with
the
highest
for
reassimilate
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formation
chy.
are numerous
Trees.
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EXAMPLES
structures
We
have
that
large
can take
developed
use to illustrate
with
three
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hierarchical
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techniques.
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phy.
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Since
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time
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of facts
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a database
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of autobiographies.
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Human
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D.
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animation
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the
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