How is display of images prevented on text-only frames?

[joakim]

I cant seem to figure it out.

My concrete problem is that I wind up here, term.c 1563:

void
produce_glyphs (struct it *it)
{
  /* If a hook is installed, let it do the work.  */

  /* Nothing but characters are supported on terminal frames.  */
  eassert (it->what == IT_CHARACTER
           || it->what == IT_COMPOSITION
           || it->what == IT_STRETCH
           || it->what == IT_GLYPHLESS);

... with a xwidget, and then the assert gets upset.

Images doesnt seem to wind up here though.

-- 
Joakim Verona