Ginga is written so that most of the functionality of the program is achieved through the use of plugins. This modular approach allows a large degree of flexibility and customization, as well as making overall design and maintenance of the program simpler.

Plugins are divided into two types: global and local. A global plugin has a single instance shared by all channels, while a local plugin creates a unique instance for each channel. If you switch channels, a global plugin will respond to the change by updating itself, while a local plugin will remain unchanged if the channel is switched, because its operation is specific to a given channel. (Ginga’s concept of channels is discussed in Channels.)

This chapter describes the set of plugins that come with Ginga. Those interested in writing their own custom plugins should refer to Writing a Global Plugin or Anatomy of a Local Ginga Plugin.

Global plugins

Local plugins

An operation is the activation of a local plugin to perform some function. The plugin manager toolbar at the bottom of the center pane is the graphical way to start an operation.