1. Chep06 1 High End Visualization with Scalable Display System By Dinesh M. Sarode, S.K.Bose, P.S.Dhekne, Venkata P.P.K Computer Division, BARC, Mumbai

2. Chep06 2 Introduction Shortcomings of present graphics systems Limited Resolution of display device Rendering Power Visualization and understanding multi terabyte scientific data Interactivity

3. Chep06 3 Cluster based visualization Why ? Current high end visualization hardware is expensive No flexibility No commodity building block Need redesign in order to keep track with faster semiconductor technology

4. Chep06 4 System Architecture A Cluster of PCs PC graphics accelerator cards LCD displays Network

5. Chep06 5 Scalable Display System at BARC Rendering Cluster 1 Master Client 16 Graphics Servers 1.7 Ghz P-IV Processors, 512 MB RAM per PC 64 MB 3Dlabs Oxygen GVX1 Pro AGP card Fast & Gigabit Ethernet Interconnection High Resolution Display Tiled 4x4 LCD panels 5120x 4096 total resolution

6. Chep06 6 Architecture Problems Cluster of PC No shared memory pool Independent graphics accelerator cards Genlock Swap lock Data lock Tiling Multiple monitors seams between monitors

7. Chep06 7 The Software Environment Client / Server Single instance of application Higher network bandwidth Synchronized program execution Multiple instances of the application Less network bandwidth

8. Chep06 8 System Software Chromium Framework for distributed rendering Client/Server approach Run existing OpenGL applications DMX (Distributed Multihead X) Distributes X window sessions across the nodes of scalable display system Run X11 applications

9. Chep06 9 Rendering Pipeline Geometry Database Geometry Transformation Rasterization Image Transformation, clipping, Lighting etc Scan-conversion, shading, visibility Per Vertex Per Pixel

10. Chep06 10 Distributed Rendering [Molnar et al. 1994] Sort-First Sort-Middle Sort-Last G R G R G R Display Database Traversal Preprocessing 3D Primitives Database Traversal Preprocessing G R G R G R Display Rendered Pixels Database Traversal Preprocessing G R G R G R Display 2D Primitives

11. Chep06 11 Sort-First configuration Tile 1 Tile 2 Tile 16 NETWORKNETWORK Crserver RenderSPU Graphics Card Server 1 Crappfacker XlibTilesortSPU Graphics Card Client... Crserver RenderSPU Server 2 Graphics Card Crserver RenderSPU Server 16 Graphics Card Packed OpenGL Commands mothership

12. Chep06 12 A view … Graphics Servers User Graphics Data 1 2 5 6 9 10 13 14 4 3 8 7 12 11 16 15 12 11 2 3 4 5 6 8 7 9 10 13 14 15 16 1

13. Chep06 13 DMX Proxy X Server X Application Back-end X server Display1 DMX Console Display2 Back-end X server Display3Display4 Back-end X server

14. Chep06 14 Graphical Control Panel Login/Logout X windows on all tiles Manage the cluster Reboot / shutdown nodes Display power management Display system information Interface for running scripts across cluster

15. Chep06 15 Applications : AnuVi Scalar Plot Vector Plot

16. Chep06 16 AnuVi Isosurfaces Ray casting Simultaneous display of multiple datasets

17. Chep06 17 Visualization of Tsunami simulation data

18. Chep06 18 CollabCAD

19. Chep06 19 Tiled MPEG/AVI movie player

20. Chep06 20 Tiled Image Viewer

21. Chep06 21 Conclusion Scalable display system with PC cluster is reasonable alternative to High-end multiprocessor, multi-pipe systems Low cost & technology tracking Deep & rich visual experience Adaptable to variety of applications & usable under various computing and display configurations

22. Chep06 22 Thanks