tréteau à devers
First, here's an example of a purlin rafter on the DP side of the hip rafter rotated into the roof surface and a jack rafter on the rotated side of the hip rafter.
Here's the drawing of how the claw lines on the folding roof surface are developed from the seat lines in plan view and the seat lines on the folding roof surface. There should always be 4 lines that define the claw-miter-bevel angles of the rafters on the roof surface. These four lines represent the center line of the hip rafter, the edge of the hip rafter, the bottom of the hip rafter plane that intersects with the roof surface and the bottom of the jack rafter where it intersects the bottom of the hip rafter.
Here's my first drawing of the Tréteaux Planche 29 with the two legs rotated into the roof surface and the two legs, hip rafters, that are plumb to the ground plane.
Here's an updated version of my drawing. Using the Tréteaux Angles Check I can see that the green footprint prism was not drawn correctly.