(Portland, OR)  --  A Portland man who's accused of killing his father after eating dinner with his parents is slated to go on trial today.  Eighteen-year-old Jacob James Simon is charged with using two swords, a knife, and a gun to kill 61-year-old Peter Anton Simon in March 2012.  After initially being ruled incompetent to stand trial, the younger Simon was deemed last April to be mentally competent enough to participate in his defense.  The defendant claims he's guilty except for insanity and didn't intend to kill his father.