database support for temporal 3d data: extending the geotoolkit
DESCRIPTION
Database Support for Temporal 3D Data: Extending the GeoToolKit. Serge Shumilov Jörg Siebeck Institute for Computer Science III University of Bonn Tel. +49 (02 28) 73-45 35 Fax +49 (02 28) 73-43 82 [email protected] [email protected]. - PowerPoint PPT PresentationTRANSCRIPT
© 2001 Institut für Informatik III, Universität Bonn
Database Support for Temporal 3D Data:
Extending the GeoToolKit
Serge Shumilov
Jörg Siebeck
Institute for Computer Science III
University of Bonn
Tel. +49 (02 28) 73-45 35
Fax +49 (02 28) 73-43 82
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 2
Previous Experience: Balanced Restoration of Structural Basin Evolution
Three time steps of the basin modeling in the Lower Rhine Basin: view from the southern part to north-east with the Oligocene bases and the antithetic faults
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 3
Geometry changes...
Example for the change of the geometry:part of the Oligocene of the Lower Rhine Basinabout 6, 9 and 13 million years ago, visualized with GRAPE
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 4
Geometry Approximation as well...
Example for the change of the topology (discretization):part of the Oligocene of the Lower Rhine Basinabout 28 million years ago, visualized with GRAPE
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 5
Localization of changes in topology
time
-20
-10
0
earth surfacefault
changes only in geometry
© 2001 Institut für Informatik III, Universität Bonn
Conceptual Model of 4D Data
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 7
Design Objectives
Allow a smooth animation on time intervals
States in between can be interpolated
Build dynamic data structures
Insert, Delete, Update operations on 4D geometries
Supports geological modelling
Separate meshes and vertices
Build several meshes from one set of vertices
Automatic consistency w.r.t. vertices
Extend 3D data types with time
Coherence
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 8
Extending the 3D Conceptual Model with Time-Moving Vertices-
Time isomorphic to the reals Location and shape of geometries
is a function of time
Vertices move on their trajectories
In our model: Trajectory piecewise linear
Change in direction => Snapshot
Linear interpolation also w.r.t. time
=> const velocity/no acceleration
Change in velocity => Snapshot
)(|)()( vv locdefttlocvtraj )(|)()( vv locdefttlocvtraj
x
y
t3010 2015
interpolated
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 9
Moving Complex Types
Assemble complex geometries from moving vertices Separates meshes from vertices
A moving simplex comprises: References to its moving vertices
Temporal interval of validity
A moving complex comprises: Set of moving simplices
Temporal interval of validity
Integrity constraints!
Moving vertex
Moving vertices span a moving triangle
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 10
Representation of time-dependent simplicial complexes applying key-frame interpolation
t
points
p0
time
pNt0
t1
t2
same datadifferent discretisation
different datasame discretisation
added triangles
remained triangles
interpolated object
( t1 < tx < t2 ) tx
representation of moving 3D points
„post“ t0
deleted triangle
„pre“ t1
„post“ t1
„pre“ t2
...
txinterpolatedvalue
storedvalue
© 2001 Institut für Informatik III, Universität Bonn
Internal Storage Representation
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 12
Why bothering?
Optimum for operations:
Store full extent for each time-step
Results in storing nt * T simplices
Optimal for space only, when discretization changes completely in each time-step
Optimum for storage space:
Store one set of moving simplices only
Time: Retrieving a time-slice results in examining nt * T simplices
Need a good compromise for
compact storage and
fast operations
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 13
Full Extents with Version Management (1)
. . .
full version delta version
. . . . . .
tt0 t1 tm-1 tm tm+1 tn-1 tntm+2
N t
k
tm tn-1tm+1 tm+2
k
tm+3
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 14
Full Extents with Version Management (2)
tt0 t1
. . .
tm-1 tm tm+1 tn-1
full version delta version
. . .
tn
. . .
tm+2
N t
k
tn-1
kN
tm tm+1 tm+2 tm+3
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 15
Comparison
N t
k
tn-1
kN
k
k
Im+1
Dm+1
Im+2
Dm+2
k
(k – kp)N
kp
kp
tm tm+1 tm+2 tm+3
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 16
Implicit Extents Utilizing Neighbour References
Stores only one ‘‘big‘‘ set of moving simplices
no full extents, no deltas
Keeps one entry point into the complex for each time-step
Maintains neighbour references
s
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 17
Using Neighbours for Implicit Time-Steps
t0 1 2
s s ss1 s
5
s4
s3
s1
s2
s3
e:[t0, t2]
s
[0, 2) : s1 [2, tx] : s4[0, 1] : null
(1, tz] : s5 [0, 1) : s2 [1, ty] : s3
Internal Representation of sInternal Representation of s
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 18
Basic Queries on Time-dependent Geometries
Time-step query
Given:
instant t, time-dependent geometry g
Retrieve a (3D) snapshot of a g at t
Time-interval query
Given:
temporal interval i, time-dependent geometry g
Retrieve a series of (3D) snapshots of g valid during i
Insertion/Deletion
Given:
time-dependent simplex s, time-dependent geometry g
Insert s into g / Delete s from g
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 19
Performance comparison (1)
time(s) nt logT(time(s)/N+log(T/N)+N) log(nt)
(time(s)/N+log(T/N)) log(nt)
Time
simplex operations
O(Nnt logT) ( kN + log(T/N), ½kN2 + log(T/N) )
kN + log(T/N)Time
interval query
O(nt logT)( ¼ kN + log(T/N), ½kN + log(T/N) )
½kN + log(T/N)Time
time-step query
(n+T) O(nT)( T(nt/N + k), T(nt/N + ½ kN)
T(nt/N + k)Space
Implicit time-step extents
Referencing
full version
Referencing
previous version
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 20
Performance comparison (2)
periodic changes
homogeneous changes
Referencingfull version
Implicit time-step extents
monotonic changes
Referencingprevious version
© 2001 Institut für Informatik III, Universität Bonn
Evaluation
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 22
Evaluation Application
Sponsor: Deutsche Forschung Gemeinschaft (DFG) Collaborative research program SFB 350 Postgraduate curriculum GRK437 Landform
Project Participants: Workgroup of Prof. Dr. A. Siehl
SFB350 subproject C4
Dept. of Geology, University of Bonn
Workgroup of Prof. Dr. A.B. CremersSFB350 subproject D4, GRK subproject A4Dept. of Computer Science III, University of Bonn
Dataset: Rheinbraun AG
Open pit mine “Bergheim”
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 23
Position of the Bergheim mine within the Lower Rhine Basin
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 24
Open pit mine within the Lower Rhine Basin
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 25
Open pit mine with giant coal excavator no. 288
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 26
Bergheim open pit mine: Position of faults and cross sections
A digitized cross-section of the Mio-Pliozene strata of Bergheim open pit mine. The hatched areamarks the filled-up part of the mine.
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 27
3D model “Bergheim” in GOCAD
0,5 km
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 28
GeoToolKit object model
SpatialObject(SO)
methods:contains(SO):BOOLintersection(SO):SOdistance(SO):REALclone():SO
Space(S)
methods:insert(SO)remove(SO)retrieve(BB):Sadd_index(AM)
AccessMethod(AM)
methods:insert(SO)remove(SO)retrieve(BB):Set<SO>BoundingBox(BB)
methods:contains(BB):BOOLintersection(BB):BB
Tetrahedron
TetraNet
Solid
Box
Triangle
TriangleNet
Surface
Plane
Segment
PolyLine
Curve
Line
PointRep
Group
R*Tree OcTree
User-Defined Access Methods
User-Defined Spatial Objects
AccessMethodClass Hierarchy
SpatialObjectClass Hierarchy
GeoToolKit Kernel
0D 1D 2D 3D
representational data type
inheritance
1:1 relationship
1:n relationship
Point
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 29
Extending GeoToolKit's Class Model
TriangleNet
3D
SpatialObject(SO)
SpatialObjectClass Hierarchy
4D
TriangleNet4D
TriangleNetElement4D
NetManager4D
TNECluster4D
PointManager
PointRep
PointCluster
PointManager4D
PointCluster4D
PointRep4D
time
prev next
under developmentrepresentational data type
inheritance 1:1 relationship 1:n relationshipattribute
NetManager
TriangleNetElement
TNECluster
Geometry Managenemt
Topology Managenemt
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 30
Database model of the Lower Rhine Basin
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 31
GeoStore
GeoToolKit
Adapter
GeoClient
Communication Infrastructure
GOCAD
VRML
Bus
3D/4D Database
Platform-independentExtensible Client-Integrator
DistributedGeoscientificTools andApplications
Communication Infrastructure
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 32
CORBA-based integrated architecture
GeoStore
transient mediator
CORBA-based communication bus
Geo-Applications
JavaClient
GeoToolKit
persistentobject
XDA Adapter
„proxy“objekt GOCAD
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 33
Application
GeoStore
Remote access to spatial data
GOCADJava-Client
3D modeling and visualization tools
Database exploration and
querying interface VRML
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 34
Special-purpose Java-Client
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 35
Visualization of the 4D model in VRML browser
t = 0
t = -10
t = -30
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 36
Conclusion and Future Work
Conclusions
Need for spatio-temporal database types
Conceptual model of spatio-temporal data adequate for our applications
Solutions to storage problem provide compromise between time/space
Based on version management
Based on implicit time-step extents
Applications
Future Work Extend conceptual model: operations on spatio-temporal types Information infrastructure New applications (kinematics of landform)
© 2001 Serge Shumilov & Jörg Siebeck Database Support for Temporal 3D Data 37
Contact information
Department of Computer Science III,University of Bonn, Germany
http://www.geo.cs.uni-bonn.de/
GeoToolKit
http://www.geo.cs.uni-bonn.de/software/geotoolkit
XDA
http://www.geo.cs.uni-bonn.de/software/xda