The UDIG GISPlatform is built around the concept of plug-ins to the base Eclipse Rich Client Platform. Several other well-known eclipse plug-ins are used, such as the Eclipse Modeling Framework (EMF) and the Graphic Modeling Framework (GEF).

It is useful to consider the UDIG application as a series of Tiers each with different responsibilities and capabilities.

If you are new to Eclipse RCP development it is helpful to go through the tutorials included with Eclipse prior to working with uDig.

GIS Toolkits

Tier 0: The Toolkits used, such as GeoTools and GeoAPI, provide useful abstractions (such as Features) and data connectivity. These libraries are all gathered into a single plug-in (net.refractions.udig.libs plugin) so they may share a classloader.

GIS Platform

Tier 1: Catalog Services provide a common API for data access and may serve as foundation for different GIS applications

GIS Application

Tier 2: Project services opperates as a UDIG application providing Maps and Printing under user control

Visualization and Interaction

Tier 3: Rendering and Tool services allow control of display and screen interaction.