This month in London, two men from Texas will look across the room towards one another. The distance between them will only be a few feet, but it will also span generations.The first man, an aging rancher whose face is shadowed by a cowboy hat, looks behind him, uncertainty in his eyes. The second man, unclothed and youthful, wears a mournful expression as he crouches on the floor, held by his male lover, who’s also naked and perched on a bed. Taken together, they’re a portrait of change—in a family, in types of manhood, and in Texas itself. The first a creature of the old ways, the second a symbol of the new, uncertain whether his forefathers have room in their land and in their hearts for…