Continuous purlin


I’m a newbie and was wondering if someone could help me with purlins. Purlins are supposed to be continuous according to IRC. So If you only have a certain length of board that is too short for the roof plane, how do you make the purlin “continuous”?
Also does it matter that the roof changes slope? These photos are of a house still under construction. To me I would say these are definitely NOT continuous, but I didn’t know if changing the angle of supports mattered. Thanks!