How should a museum mark the occasion when it’s about to shut its doors for renovation? The Art Gallery of Ontario thinks it knows: “Leading with an elite squad of eight paintball marks-people, the Argentinean-born artist [Fabian Marcaccio] is coating part of the east and west walls of the AGO’s George Weston Hall tonight for 30 minutes starting at 9:15 p.m. with an impressionistic palette of blues, whites and magentas. The instant painting ends at 9:45 p.m. But it will still be drying and fading when the space closes permanently to make way for architect Frank Gehry’s massive reconstruction of the entire gallery.” The public is invited, and the whole gooey spectacle will be accompanied by an original score for trumpets and percussion.