These are not the pictures that explain the conditions. You need to be standing as high as the deck when taking the pictures and a bit more to the right, so that he roof parts can be seen. You probably need to stand on a step ladder or find another way to take a picture from higher up.

But from what I can see, I suspect you will not be able to make a gable roof as it looks like you're experimenting with, on account of it squeezing roof drainage to a very narrow channel which, of course, would cause water problems with the roof, especially if you are in an area that freezes.