Can a structural ridge beam be used in a hip roof design?
This is the typical structure of a hip-roof:



As you can see, the ridge board, or ridge beam, is holding up the "jack rafters" at the top of the incline.

Arguably the 4 diagonal boards - the hip rafters - are holding up the ridge board on their own, but simply for load bearing purposes, place supports under the ends of the ridge board (and possibly one in the middle depending on length) because structurally speaking, the diagonal supports are in a weaker configuration than vertical ones.