#4 Portal never appears

On Debian unstable, building the source tarball results
in a TranscendApp that seems to work correctly
throughout the first level (and any later level that is
on-started by altering the command line arguments), but
no portal ever appears to the next level. Adding some
debugging output seems to show that the portal becomes
theoretically shown when I destroy the major
anti-glyph, but its radius is always zero and I can't
see it in the display.