curl and libcurl is a tool for transferring files using URL syntax. It supports HTTP, HTTPS, FTP, FTPS, SCP, SFTP, TFTP, DICT, TELNET, LDAP, POP3, IMAP, SMTP, RTSP, RTMP, and FILE, as well as HTTP-post, HTTP-put, cookies, FTP upload, resumed transfers, passwords, port numbers, SSL certificates, Kerberos, and proxies. It is powered by libcurl, the client-side URL transfer library. There are bindings to libcurl for about 40 languages and environments.
The Geospatial Data Abstraction Library (GDAL) is a unifying C/C++ API for accessing raster geospatial data, and currently includes formats like GeoTIFF, Erdas Imagine, Arc/Info Binary, CEOS, DTED, GXF, and SDTS. It is intended to provide efficient access, suitable for use in viewer applications, and also attempts to preserve coordinate systems and metadata. Python, C, and C++ interfaces are available.
libgeotiff is a library (normally built on top of libtiff) for reading and writing coordinate system information from/to GeoTIFF files. It includes CSV files for expanding projected coordinate system codes into full projections definitions and examples of transforming the definitions into a form that can be used with the PROJ.4 projections library. It also includes the sample applications listgeo (for dumping GeoTIFF information in readable form) and geotifcp (for applying geotiff tags to an existing TIFF or GeoTIFF file).
MapServer is a CGI based Web mapping application development tool. It processes user defined configuration files and templates to allow for a wide variety of applications to be developed, including interactive mapping, and spatial query definition and processing. It supports several data formats. Key features include scale dependent map rendering, automatic scalebar and legend building, feature labeling with collision avoidance, logical and thematic classifications, and on-the-fly projection of raster and vector data. The application can also access other WMS servers as a cascading map server.
Poedit is a gettext translation (.po file) editor for Unix, Windows, and OS X. It aims to provide translators with a simple, easy to use user interface with all the essential tools such as spellchecker or translation memory. It can also be used to manage translations for small projects.
PROJ.4 is a cartographic projections and datum shifting library written in C. It includes support for many (100+) projections, including Transverse Mercator and Lambert Conformal Conic. Included is a command line program for reprojecting points. It was originally written by Gerald Evenden of the USGS, and is in active use in various commercial and freeware software.
WideStudio is a multi-platform integrated development environment for building windowed event-driven applications. It uses its own independent class libraries. Automatic source code generation is provided by the application builder, which also provides project management and automatic makefile generation. WideStudio can be used to develop applications on Linux, Solaris, and Windows.