future plans for the lcd wired event display

LCD WIRED Future LCD Workshop May 19-22 2003

Joseph Perl 1

Future Plans for the LCD WIRED Event DisplayFuture Plans for the LCD WIRED Event Display

Joseph PerlSLAC Computing Services

[email protected]


Joseph Perl 2

ContentsContents

• The larger context of WIRED• Introduction to HepRep• HepRep Current and Future Architecture• Evolution from JAS 2 + WIRED 1.x to JAS 3 + WIRED 4• Features to come in WIRED 4• Demonstrations

– WIRED HepRep from:• BaBar Offline and Online via Corba• GLAST via XML• Geant4 via XML

– FRED HepRep from:• GLAST via XML• Geant4 via XML


Joseph Perl 3

Larger Context of WIREDLarger Context of WIREDLCD in JAS3

GLAST

BaBar Offline

Geant4Geant4 Web

BaBar OfflineBaBar Online


Joseph Perl 4

Limitations of Early WIRED VersionsLimitations of Early WIRED Versions(from Mark’s talk this morning)(from Mark’s talk this morning)

• One WIRED Plot per Page• No Save and Restore• No Picking Info• No easy way to extend WIRED• Memory Consumption

In response to these same issues in BaBar WIRED, we developed HepRep. This also gave us an entirely experiment independent form of WIRED.


Joseph Perl 5

The Client-Server ParadigmThe Client-Server Paradigm

• Server deals with physics, interaction with reconstruction algorithms, with our data store files etc etc

• Client deals only with graphics representations (that may be augmented with additional information that has meaning for the experiment)

• Client-server does not necessarily imply remote operation. Client and server may be on the same machine or may be on different machines. The client-server separation is in any case a useful construct to cleanly delineate the two parts of the event display solution

• Client and server communicate with an interface; the crucial point is that this interface should be simple, extensible and should accommodate all the needs seen before

• HepRep is such an interface:“A Generic Interface for Component or Client-Server Event Displays” provides for the correct distribution of computing work between the two parts of the system and effectively addresses the many important maintenance issues involved in such a system


Joseph Perl 6

The HepRep interface breaks the dependency between any particular experiment's event display server and any particular event display client.

The HepRep format is independent of any one particular language or protocol. It can be used from C++ or Java and can be shipped as Corba, RMI, XML, C++, Java or JNI for consumption by WIRED, FRED or any other HepRep-enabled event display client.

4/9/2002Joseph Perl HepRep218

*

*

*

**

*

*

1 1

1

1

1

1

1

HepRepInstance

HepRepTypeTree

HepRepInstanceTree

HepRepAttValue

HepRepType

HepRepAttDef

Linked by TypeName

ID: HepRepTreeID ID: HepRepTreeIDTypeTreeID:HRTreeIDInstanceTreeIDs:HRTreeID[]

Name: StringDesc: StringInfoURL: String

TypeName: String

X,Y,Z: Double

Name: StringDesc: StringCategory: StringExtra: String

AttDefName: StringValue: AnyShowLabel: Int

Linked by AttDefName

HepRepPoint

HepRepAction

Name:StringExpression:String

HepRepComments: String[]

HepRep: a Generic Interface Definition for HEP Event Display Representables

+getInstanceTreeTop(InstanceTreeName: String,InstanceTreeVersion: String):HepRepInstanceTree;

+getTypeTree(TypeTreeName: String,TypeTreeVersion: String):TypeTree;

+getInstances(InstanceTreeName: String,InstanceTreeVersion: String,TypeNames: String[]):HepRepInstanceTree;

+getInstancesAfterAction(InstanceTreeName: String,InstanceTreeVersion: String,TypeNames: String[],Actions:HepRepAction[],GetPoints: Boolean,GetDrawAtts: Boolean,GetNonDrawAtts: Boolean,InvertAtts: String[]):HepRepInstanceTree;

+getLayerOrder( ):String[];

+checkForException( ):String;

Comments: String[]HepRep HepRepTreeID

Name:StringVersion:String

Linked by TypeTreeID

1

HepRep

WIRED Client (Java)

Other HepRep Clients

BaBar Server

LCDInterface

GLAST Server

Geant4Server

FRED Client (C++/Ruby)

HepRep PurposeHepRep Purpose


Joseph Perl 7

HepRep is to Event Displays as AIDA is to HepRep is to Event Displays as AIDA is to AnalysisAnalysis

• Both interfaces came out of a desire to cleanly separate the desktop tool from the data source.

• Use well defined interfaces to facilitate a flexible, component architecture.

• Abstract interfaces that can be implemented in a variety of languages.

WIRED

Visualization

HepRep

JAS

Data Analysis

AIDAAbstract InterfacesBaBar, GLAST, LCD, Geant4

IceCube, CLEO


Joseph Perl 8

The “Rep” in HepRep means RepresentablesThe “Rep” in HepRep means Representables

• If one just ships references to the underlying physics objects, there are too many time-consuming callbacks, asking one by one for the points on the tracks, etc. One doesn’t achieve good separation of client-server functionality.

• The design decision behind HepRep is to serve Representables, not Physics Objects.– A Representable is the Essential Spatial Information of a Physics

Object (track, calorimeter hit, etc.) and can be augmented by that object’s Physics Attributes (momentum, energy, etc.).

– Serving Representables keeps the detailed reconstruction code, swimmers and detector models on the server side where they belong. Spatial information is assembled and shipped in an efficient manner, avoiding the overhead of too many individual method calls.

– Rendering decisions are deferred, as much as possible, to the client.


Joseph Perl 9

Example HepRep RepresentableExample HepRep Representable

A precise fitted track could be served as a set of swim step points, each augmented by helix parameters and descriptive information (track number, particle id, etc.). Only in the client is the final decision made whether to Represent this Representable as

•a dotted line,

•or as set of individual swim step momentum vectors,

•or as a set of helix segments.

Physics Object Representable Representation

FittedTrack

Track NumberParticle IDPoints(n)Helix Params(n)

Track Number: 1Particle ID: e-

Pt 1 Params

Pt 2 Params

Pt 3 Params Pt 4

Params

OR

OR

OR…


Joseph Perl 10

Example HepRep Object TreeExample HepRep Object Tree

linked by name to Type Track

linked by name to Type Track

Type Track

Instance of Track

Instance of Track

AttDefs AttVals

TypeTree InstanceTree

HepRep

Type Cluster

AttDefs

AttValsPoints

AttVals

AttValsPoints

AttVals

AttVals

Track 1 Track 2TypeEvent

AttDefs AttVals

Type HitOnTrack

AttDefs AttVals

GLAST Event multiHad/xxx

GLAST Event Types version 1.4

Flexible scheme for incremental download.Client can ask to:•include or exclude Attributes•only get Instances of a given Type•only get Instances that have given Attributes•and other options


Joseph Perl 11

The HepRep InterfaceThe HepRep Interface

*

*

*

**

*

*

1 1

1

1

1

1

1

HepRepInstance

HepRepTypeTree

HepRepInstanceTree

HepRepAttValue

HepRepType

HepRepAttDef

Linked by TypeName

ID: HepRepTreeID ID: HepRepTreeIDTypeTreeID:HRTreeIDInstanceTreeIDs:HRTreeID[]


TypeName: String

X,Y,Z: Double




HepRepPoint

HepRepAction

Name:StringExpression:String

HepRepComments: String[]

+getInstanceTreeTop(InstanceTreeName: String,InstanceTreeVersion: String):HepRepInstanceTree;

+getTypeTree(TypeTreeName: String,TypeTreeVersion: String):TypeTree;

+getInstances(InstanceTreeName: String,InstanceTreeVersion: String,TypeNames: String[]):HepRepInstanceTree;

+getInstancesAfterAction(InstanceTreeName: String,InstanceTreeVersion: String,TypeNames: String[],Actions:HepRepAction[],GetPoints: Boolean,GetDrawAtts: Boolean,GetNonDrawAtts: Boolean,InvertAtts: String[]):HepRepInstanceTree;

+getLayerOrder( ):String[];

+checkForException( ):String;

Comments: String[]HepRep HepRepTreeID

Name:StringVersion:String

Linked by TypeTreeID

1


Joseph Perl 12

HepRep AttributesHepRep Attributes

Any number of Attributes can be hungfrom a Type, Instance or Point.There are four Categories of Attributes:•Draw Attributes (such as thickness, color and what shape to draw from the points) can be modified in the client through a draw attribute editor•Physics Attributes (such as track momentum or hit error) can be used for visibility cuts (client side or server side)•PickAction Attributes define special things to do when the user picks on the Representable (such as remove hit and refit track)•Association Attributes define loose associations between Representables (such as track cluster matching)

*

*1

1

1

HepRepInstance

HepRepType

Linked by TypeName TypeName: String

X,Y,Z: Double

HepRepPoint

**1 1

HepRepAttDef


*


HepRepAttValue




Joseph Perl 13

HepRep Current Use ArchitectureHepRep Current Use Architecture

While all four experiments are now using WIRED, and two can use FRED,they use a variety of HepRep and legacy implementations:• BaBar has a HepRep1 Corba server, dependent on BaBar code.• LCD passes WIRED java objects using a legacy data format (pre-HepRep).• Geant4 has abstract HepRep1 and HepRep2 implementations to XML and Java. • GLAST has an abstract HepRep2 implementation to XML and Corba.

HepRep1HepRep2+legacydata formats

LCD(java)

Javalegacy format

WIRED 3 (Java)

XML

HepRep2FRED(C++/Ruby)

GLAST(c++)

HepRep2

BaBar(c++)

CorbaHepRep1

Geant4(c++)

XMLHepRep1

Corba

RMI

Java

XML

Corba

XML

Corba

LCD Application

GLAST XML/Corba Streamer

BaBar Corba Server

Geant4 XML Streamer / Java Builder HepRep2 Java

XML


Joseph Perl 14

HepRep Near-Term Future ArchitectureHepRep Near-Term Future Architecture

HepRep2

LCD(java)

XML

HepRep2GLAST(c++)

HepRep2

BaBar(c++)

CorbaGeant4(c++)

Corba

RMI

Java

XML

CorbaXML

C++

C++ Shared HepRep Factory

Java

All data sources speak HepRep2 to an abstract HepRep factory (from FreeHEP).By instantiation of one or another concrete implementation of HepRep:• a C++ program can change from creating HepRep in C++ memory• to creating HepRep as an XML streamer (a pure C++ solution with no external library dependencies and no creation of the HepRep in memory)• to creating HepRep as Corba streamer (depends on Corba libraries)• or creating HepRep as Java (via Java Native Interface)

HepRep2CorbaXML

JavaRMI

IceCube(java)

Java Shared HepRep Factory

WIRED 3 (Java)

FRED(C++/Ruby)


Joseph Perl 15

Evolution from JAS 2 + Wired 1.x to JAS 3 + Wired 4

Generic Wired 3.x Application

BaBar Corba HepRep1

Geant4 XML HepRep1&2

GLAST XML HepRep2

LCD Java Not HepRep

JAS 2LCD Wired 1.x JAS plug-in

Up to Last Week

Generic Wired 3.11 Application

BaBar Corba HepRep1


GLAST XML HepRep2

LCD Java Not HepRep

JAS 3LCD Wired 3.11 JAS plug-in

Today

JAS 3

BaBarXML, JNI & Corba HepRep2

Geant4 XML, JNI & Corba HepRep2

GLASTXML, JNI & Corba HepRep2

Generic Wired 4 JAS plug-in

Eventual Goal

LCD Java, XML & RMI HepRep2

Soon

Generic Wired 3.x Application

BaBar Corba HepRep1&2


GLAST XML & Corba

HepRep2

LCD Java HepRep2

JAS 3LCD Wired 3.x JAS plug-inGeneric Wired 3.x

JAS plug-inGeneric Wired 4 JAS plug-in

Got all experiments onto same WIRED base version. Many new features for LCD.

Get all experiments onto HepRep. Allows attribute picking for LCD.

WIRED 4 has HepRep2 as its backbone. Allows us to exploit the full capabilities of HepRep

Babar, Geant4 and GLAST users can switch from WIRED 3 to 4 whenever they choose, since either WIRED can handle HepRep2


Joseph Perl 16

Features to Come in WIRED 4

Because Wired 4 will use HepRep2 as its backbone, many advanced features anticipated in the HepRep2 design will become possible:

•Provide a tabular “text” view of the event, showing all attributes and making all attributes editable.

•Allow easy save and restore of user preferences for attribute settings for any particular HepRep Type.

•Support interactive cuts on attributes.

•Allow graphics objects to be labelled with any one or more of their HepRep attributes (e.g., PT=0.4, PID=electron).

•Use association attributes to do things like: “highlight the calorimetry data associated with the selected track” or color all tracks by particle ID in one view and color them by energy in another view.

Wired will pick up various convenient features from JAS 3:

•Save and restore current configuration such as number, position and orientation of graphics windows.

•All text entered into input areas of dialog boxes becomes part of pull down menu of options for rest of that session and future sessions

JAS 3

BaBarXML, JNI & Corba HepRep2

Geant4 XML, JNI & Corba HepRep2

GLASTXML, JNI & Corba HepRep2

Generic Wired 4 JAS plug-in

Eventual Goal

LCD Java, XML & RMI HepRep2


Joseph Perl 17

DemonstrationsDemonstrations• WIRED

– a HepRep client written in Java based on FreeHEP

• Full-featured• Runs in JAS or as separate app• Demos

– HepRep from BaBar offline and online via Corba

– HepRep from Geant4 and GLAST via XML

– HepRep from Geant4 via JNI

• FRED– a Heprep client written in C++/Ruby

based on the Fox toolkit• Less features than WIRED, but

could be extended• Limited functionality, but does

include scripting• Demo

– HepRep from GLAST and Geant4 via XML


Joseph Perl 18

ReferencesReferences

• HepRep: a generic interface definition for HEP event display representableshttp://heprep.freehep.org

• HepRep Complete Presentation (most complete description of HepRep)http://heprep.freehep.org/heprep2.Complete.ppthttp://heprep.freehep.org/heprep2.Complete.pdf

• Fred: oh no, another event display (a HepRep client)http://www.fisica.uniud.it/~riccardo/research/fred

• WIRED: world wide web interactive remote event display (a HepRep Client)http://www.slac.stanford.edu/BFROOT/www/Computing/Graphics/Wired

• SLAC HepRep WIRED Work Planhttp://www.slac.stanford.edu/~perl/wired

• A Component Approach to HEP Event Displayshttp://www.slac.stanford.edu/~perl/component

• Requirements for a New BaBar Event Display (most parts apply to any exp)http://www-sldnt.slac.stanford.edu/hepvis/paper/paper.asp?id=37

• The FreeHEP Java Libraryhttp://java.freehep.org

http://www.slac.stanford.edu/~perl/wired

future plans for the lcd wired event display

Documents

string desc

string infourl

string checkforexception

string extra

string category

string value

physics object track

underlying physics objects