Drawing showing the plane that defines the lower claw angle on the rotated hip rafter.
Drawing showing the hip rafter head cut unfolded. It also shows the 2 parallelogram planes that represent the head cut on the hip rafter. To layout the head cut on the timber you need 4 different angles and 1 dimension. The 2 upper claw angles that form one of the parallelogram cutting planes and the 2 lower claw angles of the rotated hip rafter that form the other parallelogram cutting plane. It's important to remember that the cutting planes are always parallelograms. Once you layout 2 of the angles of the parallelogram then the other 2 sides of the parallelogram are automatically developed by using the same 2 angles.
Drawing showing the geometry for the 2 upper claw angles and the 2 lower claw angles.
Drawing showing the intersection of the DP Lines.