Sigmar Polke, an artist of infinite, often ravishing pictorial jest, whose sarcastic and vibrant layering of found images and maverick painting processes left an indelible mark on the last four decades of contemporary painting, died Thursday in Cologne, Germany. He was 69.

The cause was complications from cancer, said Gordon VeneKlasen, a partner at the Michael Werner Gallery New York which, along with Galerie Michael Werner in Cologne, has been Mr. Polke’s chief representative for nearly 20 years.

Mr. Polke (pronounced POLL-ka) was nearly as influential as Robert Rauschenberg, Jasper Johns and Andy Warhol, the postwar titans who made his own work possible. And ultimately his influence could even exceed theirs through its sheer diversity, stylistic promiscuity and joyful, ruthless exploitation and expansion of the ways and means of several mediums.

He made prints and sculpture and in his youth, and dabbled memorably in Conceptual and installation art, with potatoes being a favored material. His peregrinations in and around the mediums of drawing and photography were extensive, meriting enormous retrospectives and forming second and third careers.