desktop geographical information system

QGIS aims to be an easy to use GIS, providing common functions and features. The initial goal was to provide a GIS data viewer, but now it also permits to edit, create and analyze lots of spatial datas. QGIS supports a number of raster and vector data formats, with new support easily added using the plugin architecture. Supported formats are : - spatially-enabled PostgreSQL tables using PostGIS. - most vector formats supported by the OGR library, including ESRI shapefiles, MapInfo, SDTS and GML. - raster formats supported by the GDAL library, such as digital elevation models, aerial photography or landsat imagery. - online spatial data served as OGC-compliant WMS or WFS.

mesh data abstration library

Mesh Data Abstraction Library (MDAL) is a C++ library for handling unstructured mesh data released with MIT license. It provides a single data model for multiple supported data formats. MDAL is used by QGIS for data access for mesh layers.

geospatial routing extension for PostgreSQL

pgRouting extends the PostGIS / PostgreSQL geospatial database to provide geospatial routing functionality.

Advantages of the database routing approach are:

• Data and attributes can be modified by many clients, like QGIS and uDig through JDBC, ODBC, or directly using Pl/pgSQL. The clients can either be PCs or mobile devices.
• Data changes can be reflected instantaneously through the routing engine. There is no need for precalculation.
• The "cost" parameter can be dynamically calculated through SQL and its value can come from multiple fields or tables.