In Rose Troche’s powerful, passionately acted film version of A.M. Homes’ 1990 story collection, four suburban families converge after a tragic accident in The Safety of Objects. Glenn Close plays the mother of a musician (Joshua Jackson) who’s now in a coma; Patricia Clarkson is a neighbor who’s endured a nasty divorce; and Dermot Mulroney is a lawyer who becomes unhinged at the local mall after losing a promotion. Yes, the tone — not to mention the lighting — is dark. But flashes of wit lighten up the story. ”God has a wicked sense of humor,” says Close’s character. So does this funny-sad film. EXTRAS It would be interesting to hear from Troche (”Go Fish”) about her writing and directing process, and also from Homes to find out what she thinks of the adaptation — but there isn’t any commentary. Instead, the DVD offers only three trailers (for ”Casa de los Babys” and Showtime’s ”Dead Like Me,” in addition to ”Safety”), and the movie’s English and Spanish subtitles.