long line in GtkTextBuffer

[Nick Watts <fatalglory gmail com>]

I'm writing an application which largely consists of a text editor based 
around the Gtk multiline text widgets. My problem is that when I use 
gtk_text_buffer_set_text() to set the text in the widget, I have display 
issues with large lines.

I would probably never have realised except that I tried to open a very 
complex svg file made with inkscape in my editor and it opened fine 
but when the text was rendered, the really long line (one extremely complex 
path element generated with the trace bitmap function) was simply invisible 
and the whole application started moving at a snails pace. It's a fairly 
fast computer so I don't think resources are the issue (the whole svg file 
is only 12Kb). Anyone have any ideas?