MANILA, Philippines–Sleep-deprived, Filipino-American filmmaker Ramona Diaz’s mind was swirling with all sorts of “compelling” images: African-American girls dancing and chanting “Pen-pen de Sarapen.” An American school principal and janitress swaying to “Pinoy Ako [I’m Filipino],” the theme of the ABS-CBN reality show “Pinoy Big Brother.” And her film’s Caucasian cinematographer insisting on changing his citizenship to Filipino.