IDV Development Status Report

Don Murray
May 13, 2003

This report updates the status of Unidata's IDV development efforts reported at the last Policy Committee meeting.

Objectives

The long-term objectives of Unidata's MetApps Development Initiative are:

Deliver turn-key platform-independent applications for the analysis and visualization of meteorological data. These applications must provide and extend the most important capabilities of currently-available applications such as GEMPAK, GARP, and McIDAS. Use of these applications should require no knowledge of Java or component architectures.
Deliver easily installed executables, user documentation, and test cases for the turn-key applications.
Identify or create a component-oriented framework that supports construction of custom applications from components used to build the turn-key applications. This framework should be useful to create new combinations of components that provide subsets of the capabilities of the turn-key applications, connect them in unanticipated ways, or provide tailored mini-applications for embedding in educational materials. Use of these components may require knowledge of component architectures or Java.
Deliver full source code, class documentation, and test cases for the MetApps components.
Enlist other developers in enhancing components and developing new components for the framework by providing an archive, mailing list, developers' forums, documentation, web site, and support for the components.

To accomplish these long-term goals, short-term objectives include the delivery of incremental releases involving users, incorporating feedback, refining the development process, and enhancing the software with each release.

Progress to Date

Development of the Integrated Data Viewer (IDV) is underway to meet the goals listed above. The IDV reference application embodies goals #1 and #2 listed above. This application is being used to develop and test the framework listed in goals #3 and #4 above. A developer's manual is in progress to satisfy goal #5.

In more detail, recent accomplishments include:

Since the last report, 2 additional beta releases (beta5 and beta6) of the IDV have been made. Each update has included new features as well as bug fixes. The final, non-beta release of IDV 1.0 is scheduled for mid-June in time for the Unidata summer workshop. The IDV can be downloaded at http://www.unidata.ucar.edu/software/idv/. Features added since the beta3 release include:
- New data/display selection widget. This is the most significant User Interface change. The DataSelection widget replaces the old DataSources tree widget. It allows easier selection of datasources and displays from within one widget.
- Reworked netCDF grid reading code. This will allow us to handle more types of grids, including AWIPS netCDF files.
- Wind profiler time/height displays
- Isosurfaces colored by another parameter (e.g. windspeed colored by geopotential altitude)
- A more robust color table editor
- Users can now interactively select which display types they wish to use in the application through the User Preferences editor.
- Various and sundry bug fixes, including:
  - winds in station model plots don't drift
  - maps now display correctly on global grids

As a follow-up to the Unidata/ATD collaboration on using IDV in the field during the IHOP project, discussions are underway to determine how the IDV might be used in a future field project to access field data in the classroom. See Dave Carlson's report for more information.

Collaboration has continued with DLESE on the continued development of the Visual Geophysical Exploration Environment (VGEE) using the IDV framework. This provides us with another way to test and improve the framework for people creating custom applications. Rajul Pandya, is the main contact for this effort. VGEE curriculum materials are now indexed in DLESE. These include links for launching pre-configured versions of the VGEE/IDV pertinent to the learning activity. Dan Bramer (UIUC) will be visiting the UPC in late May to work with the IDV developers on connecting the VGEE concept models to the data available through the IDV.

The IDV and THREDDS development groups have been working to define the needs of IDV as a THREDDS client. This effort includes developing THREDDS capability servers which can be queried for effective access to data and to provide user interface (UI) definitions based on XML. IDV can now access data from other, non-Unidata THREDDS catalogs (e.g., CDC)

At the last User Committee meeting and in subsequent e-mail discussions, it was decided that an IDV Steering Committee should be formed to guide future development efforts. The goals of this committee are:
- prioritize the development efforts based on the percieved needs of the Unidata community and other interested parties and input from the IDV developers on feasibility and cost.
- sets list of large focused development efforts on the range of 3-6 months. These would include:
  - types of data to support
  - new types of displays to implement
  - new means of use (publishing, collaboration)
  - organizational collaborations
  - educational content
- test implementations and provide feedback. Releases to the committee will occur on a 1-2 month time frame.
This group will report to the Unidata User's Committee just as the MetApps Task Force that proceeded it.

Current development beyond what's listed above for the full 1.0 release includes:

Enhancement of support for Level II Archive Format in the IDV.

Continued improvements in the profiler displays (decluttering, labelling). Use of THREDDS middleware (DQC) to select the data.

Improvements in station model plotting and station location plotting including use of fonts, decluttering and better symbol handling.

Use THREDDS capability server work to develop a cohesive framework for accessing local and remote datasets. This includes the ability to save off time relative (i.e. latest data instead of absolute times) pointers to datasets.