   Nevermind I trashed my code
  So I'm making a quad-tree. So essentially I am flattening the Camera Frustum(to the X/Z axis), and testing to see if it holds a bunch of squares or intersects them. The faster the routine the better. If it helps at all my square is a true square(equal length and width).edit:It's recently come to my attention that a trapezoid is just one truncated triangle. Thanks IRC haha. So now I just need to figure out how to test is a square is in a triangle.[Edited by - Cakey on June 22, 2009 5:22:54 PM]
  Is it going to be significantly slow to test every single point? With a method such as:private bool isPointInTriangle(Vector2 Point, Vector2 A, Vector2 B, Vector2 C){float Orientation1 =   Orientation(A, B, Point),Orientation2 = Orientation(B, C, Point),Orientation3 = Orientation(C, A, Point);if(Orientation1 == Orientation2 && Orientation2 == Orientation3){return true;}else{return false;}}private int Orientation(Vector2 Begin, Vector2 End, Vector2 Point){//Linear determinantfloat Orin = (End.X - Begin.X) * (Point.Y - Begin.Y) - (Point.X - Begin.X) * (End.Y - Begin.Y);if (Orin > 0.0){return 1;}  //Orientation to the rightelse if (Orin < 0.0) {return  -1;} //Orientation to the leftelse{return 0;}   //Orientation is middle bound}(Also I dunno if that code is right I have yet to test it)   