David W. Walker Ian J. Grimstead Cardiff School of Computer Science david@cs.cf.ac.uk

2. David W. WalkerIan J. GrimsteadCardiff School of Computer Sciencedavid@cs.cf.ac.uk RAVE:Resource-AwareVisualization Environment

3. Presentation Structure • Data Visualization: Pros and Cons • A Solution: The RAVE project • Demonstration of RAVE • How RAVE works • Future Work • Conclusion

4. ...or too little Too much info... Data Visualization:Simulations • Test theories without physically building • Cheaper to construct new tests • Can run for long periods without human intervention • Simulations produce lots of information • But - hard to understand...

5. Image courtesy of IBM Research Generated with IBM Open Visualization Data Explorer Data Visualization:Comprehension • Solution–graphical visualization of data • View a model of the data, not the data • Massachusetts Bay • Colours, contours,... • Easier to comprehend • Data is now interactive

6. Data Visualization:Machine Dependence • System is often single platform • Microsoft vs. UNIX vs. Apple Mac vs. ... • Handheld vs. workstation vs. ... • Need to buy more copies of the system!

7. Data Visualization:Multiple Users • Hard to collaborate with other users • Usually – must all crowd around one machine • Unless a large display is available • One person “driving” – others are passive • System is not assisting with collaboration

8. Data Visualization:Specialist Equipment • May require specialist computer • Capable of displaying complex data • Prohibitively expensive to own • User may need to move to machine • Problem if only one machine • Overloaded – too slow to be usable • All displays are in use • What if it breaks?

9. Data Visualization:Summary • Pros: • Can comprehend much more information • Data is now interactive • Cons: • Restricted to specific machine/platform • May require specialist computer • Hard for users to collaborate

10. A Solution:The RAVE Project • RAVE supports: • Various types of machine/display • Immersadesk → workstation → PDA • Multiple machines/resources • Resource-aware: network, machine load • Multiple users • Resource sharing • Collaboration • RAVE is now demonstrated...

11. Demonstration(via Screenshots) • Recorded demo – screen shots • Resources: • Windows laptop (thin & active clients, Java) • Remote Linux/Solaris/IRIX servers • Data servers + Render servers • PDA (thin client, C++/QTopia) • Used: • WeSC UDDI server • WeSC Service-Orientated Grid

12. Run UDDI Manager

13. Create Data Service

14. Active Client Can now interact with scene Select interaction Drag mouse/stylus to activate interaction (move/rotate/etc)

15. Create Render Service

16. Thin Client

17. Tiled Rendering

18. The RAVE Project:How it Works • Each RAVE component now examined: • Data Distribution – Data Server • Displaying the Data – Active Client • Lightweight clients – Render Server, Thin Client • Service Discovery • Tiled rendering with Active Client • Remote (dynamic) data feed

19. Internet or remote machine RAVE Client RAVE Client RAVE Client Visualization Data Data to be visualised Data Server Data Distribution • First component: Data Server • Acts as a distribution point & interpreter • Understands many types of data • Uses Java3D+Xj3D as importer

20. Visual drawn on local machine Visualization Data Data Server Isosurface of MRI from Large Geometric Models Archive (~850kpoly, 3 nodes, 19.8Mb raw data) Bootstrap DS→AC: 12.4s Note: Windows XP Diffusion Tensor Imaging, SHEFC Brain Imaging Research Centre for Scotland, Martin Connell and Mark Bastin (~950kpoly, 2200 nodes, 29.8Mb raw data) Bootstrap DS→AC: 20.9s Geology dataset (10 minute ETOPO from National Geophysical Data Center (~4.6Mpoly, 3 nodes, 109.6Mb raw data) Bootstrap DS→AC: 48.3s Displaying the Data • Second component: Active RAVE Client • “Active” – facilities to draw on its own • Accepts feed from Data Server • Presents images of data to user Active RAVE Client

21. Lightweight Clients Visual drawn off-screen (hidden) Visual Interaction Visualization Data Render Server Thin Client Data Server MolScript VRML of 1PRC molecule (Research Collaboratory for Structural Bioinformatics – Protein Data Bank) (~546kpoly, 29,000 nodes, 23.2Mb raw data) 96.5s DS→RS (# nodes) 3.2fps @ 400x400 (11Mbit shared wireless) Isosurface of MRI scan Large Geometric Models Archive (~850kpoly, 3 nodes, 3.2fps @ 400x400 11Mbit wireless) • Third component: the Render Server • Drawn visual sent to Thin RAVE Clients • “Thin”-insufficient power/resources to draw data

22. Performance / Issues • Performance with Java3D • NVidia Quadro FX 700 off-screen rendering • ~37 Mpoly/sec with DTI dataset (~950kp) • ~0.8 Mpoly/sec with galleon (~5.5kp) • Needs high polygon scenes • Waits too long before buffer flip? • Issues with Java3D • Tricky to release memory • Had to be brave and produce IA64 build • Off-screen rendering requires on-screen window (IRIX)

23. Service Discovery • Servers are “advertised” on the network • Using standardised methods • UDDI, Grid/Web Services • We can reuse the work of other people • UDDI4J, Apache Axis, Globus • Human user can see list of servers • Select most appropriate one • Consider speed, memory, bandwidth... • May already have your required data on it • Or automatically select with a heuristic

24. UDDI Server Search for RS Drawn Visual Render Server Render Server Available RS Drawn Visual Tiled Rendering • If your machine can nearly cope: • Request assistance from a Render Service • Automatically select RS with heuristic • Locally render subset (tile) of data • Remainder rendered by Render Server Visualization Data Active Client Data Server

25. Remote, Dynamic Data • Independent simulation can supply Data Server • Simulation code instrumented • Transmits scene creation to Data Server • Subsequent updates also sent • Data Server reflects updates • Multiple clients can view live simulation

26. Connection to AccessGrid RAVE can supply AccessGrid • Render Server supplies H.261 video feed • Wide-area distribution of visualization • Interact with existing clients.

27. AccessGrid and RAVE

28. Summary • Data Server reads data and distributes • Active Client renders locally • Thin Client renders via Render Server • Active Client may request assistance • All resources shared where possible • Uses Java to support (most) platforms

29. Current & Future Work • Data Server stream actions to disk (done) • Asynchronous collaboration through playback • Automated migration of services • Implementation of failsafe • Collaboration support • Gesticulation, data mark-up • Further resource-awareness • Image compression, data down-sampling • Further investigation of work distribution • Scene graph distribution

30. Conclusion • Visualization – great! • But requires specialist hardware or software • Often not designed for multiple users • Solution - “RAVE” • Utilise any available machines/resources • Collaborative – work from your desk • Further information: • http://www.wesc.ac.uk/projectsite/rave/

31. Acknowledgements • Project funding: UK DTI & SGI • Diffuse Tensor Imaging dataset: • Martin Connell and Mark Bastin, SHEFC Brain Imaging Research Centre for Scotland • Molecule geometry: • Research Collaboratory for Structural Bioinformatics Protein Data Bank, using MolScript • Skeletal hand: • Large Geometric Models Archive, Georgia Institute of Technology • ETOPO dataset: • National Geophysical Data Center (NGDC)