E.S.O.V. Case study
Dvolution Case Study for the European Space Agency
Earth Swath & Orbit Visualisation
The European Space Agency (E.S.A.) Envisat-1 is an advanced polar orbiting Earth observation satellite that provides measurements of the atmosphere, ocean, land, and ice. It is expected to be in orbit for at least five years. E.S.O.V. is a software package that provides the user with the means to visualize where each instrument on the satellite will be effective on its orbit of the Earth.
The European Space Agency approached us to deploy our expertise in cross platform development to the huge amount of legacy code that constituted the ESOV product. In order to create a single source base it was necessary to restructure large portions of the code for efficiency and update it for C++.
The challenge in enabling a single source code base regardless of platform was to remove all of the platform specific references to libraries that are not common. To do this we created mapping classes that reflect the Microsoft Foundation Classes and the Motif Toolkit for UNIX and LINUX based Operating systems for each of the graphical components used in the Application.
Using the Java API as a loose model for the graphics we devised a set of drawing routines that allowed us to make use of the same graphics calls to draw the Earth in its various projections and all of the satellite and plotting details. This generic library allows all of the graphics calls to work regardless of operating system platform.
After the initial ‘port’ to windows we were contracted to begin adding new features to the base product and also to enhance the existing mechanisms. New features included PDF generation, visualisation projection for the recently launched Artemis satellite, new outputs for satellite and instrument visibility on the Earth’s surface as well as significant interface enhancements. We also created a “plug-in” mechanism to allow other satellites to be added to the system as and when required by the creation of a simple configuration file. This allowed E.S.A. to use the product with their Cryosat and SMOS satellite projects.
