1. This talk is available on the web at:

http://www.intergalact.com/cscgi/sept99talk/

All software, and more information about CSCGI is available at:

http://www.intergalact.com/cscgi/

2. What is CSCGI?

• CSCGI allows a web browser to access and interact with stand-alone CGI programs without the use of an internet connection or a web server.
  
  CGI dataflow vs. CSCGI dataflow:
  
  
  
  
• Over a network, a web browser can call an external CGI program using internet connection software and a remote web server.
  
  
• On a local system, the web browser can call a CSCGI program directly, without a network, an internet connection, or a remote web server.

• CSCGI links HTML forms and Javascript in a webpage to a Java class interface to a Netscape plugin.
  
  
• The Netscape plugin launches and communicates with an external CGI program.
  
  
• Data returned from the CGI program is used to display a new webpage, or can be sent to Java applets embedded in the page.

3. Forms parser demo.

• HTML forms data are collected and converted to URL encoding by a Javascript function.
  
  
  
  
• Input data, environment variables, and command line are sent to a stand-alone CGI program by a Netscape plugin embedded in the webpage.
  
  
• CSCGI library code in the external program parses the input data and converts names and values back to plaintext.
  
  
• The external CGI program creates an "on-the-fly" HTML page listing all input data.
  
  
• This page is returned to the browser for display.
  
  
  
  

4. 3d surface generation and display applets.

• CSCGI can be used to give Java applets file reading and writing access.
  
  
• Data can be transferred between Java applets and disk files in either text or binary mode.
  
  
• The surface generation applet creates and saves a set of binary surface data, generated by an interactive equation in the applet.
  
  
  
  
• The surface display applet can read a binary data file (in either PC or Mac byte ordering) and display the result as a 3d surface.
  
  
• The resulting 3d surface can be rotated and zoomed in realtime.
  
  
  
  

5. PDS CD-ROM image database search.

• The PDS search system can retrieve spacecraft images from a CD-ROM.
  
  
• This system searches for images within a database contained on the CD-ROM.
  
  
• Images are decompressed from a proprietary format.

Search system files and programs:



Search page:




• The "cdsearch" program creates "on-the-fly" HTML pages showing the results of the search, and creates a directory of JPEG thumbnail images.
  
  
  
  
• The "showimage" program creates a full-size JPEG image from the compressed PDS image file, and allows the brightness and contrast of the resulting image to be changed by the user.
  
  
  
  
  File information page:
  
  
  
  

6. Current Research.

• We are currently working with a group at Harvard University to use CSCGI to create a local CD-ROM database of art history, using existing remote PERL programs.
  
  
• Automatic generation of HTML search pages from a search-layout page and associated CSCGI program (with no end-user programming).
  
  
• Automatic encapsulation of legacy data (e.g. VAX records, PDP diskpacks, magnetic tape) into modern machine-readable format (using HTML META tags or XML) for use with "standard" search engines (again with no end-user programming).
  
  
• Use of Netscape and HTML as a common user interface for accessing heterogenous database structures and data types.

7. Future Uses.

• Migrate existing websites to CD-ROM or hard disk (for running CGI programs when no network is available).
  
  
• Run existing legacy code from a webpage (exploiting Netscape as a GUI).
  
  Example: web interface to NAIF ephemerides generators.
  
  
• Possibilities outside astronomy:
  
  
  • Hyperhelp (similar to MS help facility) with cross-linked references, no network involved.
    
    
  • Library search/query tools for databases on local CD-ROM or hard disk.
    
    
  • Control of 3rd-party "scriptable" programs from a webpage, using additional technology such as AppleScript applets and droplets.