“Painting 2012” is a stunning reminder of the central place photography holds in Gerhard Richter’s oeuvre, even with regard to his abstract paintings. Here, he used a digital process to transpose a painting from 1990 into a series of unique photo images of thousands of narrow, variegated horizontal bands. A large plate-glass sculpture in the back gallery fractures the stripes as one circulates the space, enhancing the dizzying installation.