gtk:cell-renderer-render (renderer cr widget background area flags)

renderer -- a gtk:cell-renderer object
cr -- a cairo:context-t instance with the context to draw to
widget -- a gtk:widget object owning the window
background -- a gdk:rectangle instance with entire cell area including tree expanders and maybe padding on the sides
area -- a gdk:rectangle instance with the area normally rendered by a cell renderer
flags -- a gtk:cell-renderer-state value that affect rendering

Invokes the virtual render function of the cell renderer. The passed-in rectangles are areas in cr. Most renderers will draw within area. The xalign, yalign, xpad, and ypad properties of the cell renderer should be honored with respect to area. The background argument includes the blank space around the cell, and also the area containing the tree expander. So the background rectangles for all cells tile to cover the entire window.