1. Computer Supported Collaborative Visualization C S C V Sun-In Lin lsi@cs.nchu.edu.tw

3.  Traditional Scientific-Visualization software can only help one man visualize some data on his desktop. Scientific Visualization

4.  Collaboratively Visualizing data set on a desktop at different LOCATIONS, even at different TIME -- CSV. Collaborative Scientific Visualization

5.  WCV: Collaborative visualization system using web-styled user interface.  WCV extended from Computer Supported Co- operative Work (CSCW). Web-Based Collaborative Visualization

7.  Developing a collaborative visualization system enabling to support both “synchronous” and “asynchronous” operations. ※ System Design Goal (1) ※

8.  Shared-Screen ： Remote Display (X-Window)  Shared-Image: Sending Rendered Images (centralized Approach)  Shared-Control: Sending Control Parameters (Distributed Approach)  Sharing viewpoint 、 camera 、 visualization attributions 、 collaboration contents, etc. ※ System Design Goal (2) ※

9.  Requiring a cross-platform system supporting various operating systems for several hardware platforms. ※ System Design Goal (3) ※

11.  Member Service: Member Server and Member Client.  CV Service: CV Server and CV Client.  Advantages: two services are with independency.  Adopting Visualization Toolkits (VTK) ※ System Architecture (1) ※

12.  Dual servers with three execution modes. ※ System Architecture (2) ※

13.  Double View-Windows: Global and Local View. ※ System Architecture (3) ※

15.  Member Server Side. ※ System Architecture (4): Member Server ※

16.  Member Client Side. ※ System Architecture (5): Member Client ※

17.  CV Server Side. ※ System Architecture (6) ※

18.  CV Client Side. ※ System Architecture (7) ※

19.  Security Issues. ※ System Architecture (8) ※

20.  Qualification Table Maintenance. ※ System Architecture (9) ※

21.  Global Execution Architecture: an overview. ※ System Architecture (10) ※

23.  Global execution procedure: an overview.

24. ※ Development Components ※

25. ※ Implementing NPR Function (1) ※

26.  Critical techniques ※ NPR Functions (2) ※

27. ※ Model Editing ※

28. ※ Converting Scripts to C Source ※

30.  1. Network Transmission Speed  2. Numbers of Collaborative Member  3. Collaborative Model Complexity  4. Hard Disk Access Speed in the CV Server  5. Processing Speed in the CV Client  6. Collaborative Operations

32. Test Scene

33. Test Environment

34. Network Traffic

35. Timing for 200 Operations in Seconds

36. ※ Bottleneck of Real Time Collaboration ※  Network Transmission Speed  Collaboration is proceeded by sending the control parameters with small amounts of data, being independent on the network transmission speed.  Hardware in the Client Side  Complex models require high-performance hardware in the client side to reach real time collaboration.  System Bottleneck  System bottleneck is at the speed of hardware capability in the client side, not depending on network transmission speed.

42. An Example for NPR Rendering

45.  Collaborative Model-Editing.  More NPR Rendering.  Further Performance Analysis.  Security Improvement.  System Maintenance. ※ Future Work (1) ※

46. ※ Future Work (2) ※

47. T D C S V S Thanks! Q & A