R

reference count

A counter associated with an object that keeps track of the number of references to the object. When the reference count goes to zero, the memory manager removes the object. Every GObject instance has a reference count.

renderer

An object that displays a cell in a tree view. A renderer is active over an entire column in the view; a column may have more than one renderer.

RGBA

Red/Green/Blue/Alpha. The normal format for a color value of a monitor pixel with transparency.

row reference

A permanent marker on a node in a tree model; row references are the tree equivalent of text buffer marks .