Point offset about Chinese style pavilion

hello,I want make a Chinese style pavilion(p.1) in grasshopper and now I faced so much problem, can anyone help me I want create retangles like p.3 the retangle need slope.

六角涼亭.gh (13.7 KB)

One way of creating the rafters: 六角涼亭_ME.gh (22.5 KB)
Using control points for retrieving the corner points results in seven points (duplicate point), instead use discontinuity.