That’s very easy via code but I guess that this “option” is a no-no for you. So you should wait for some other good Samaritan to solve that one (the LBS part, that is) via native GH components.
BUT … the fabric concept is wrong since it yields a shading shape that (a) covers a very small percentage of the footprint (so what’s the purpose of doing it?) PLUS (b) is “linear” in U (or V). In order to achieve a real-life tensile membrane like this one you should use the one point up the next down rule otherwise you would apply colossal forces to stabilize the membrane with absolutely no reason. This would affect the sizes of the LBS members/nodes/anchor plates etc etc. Solving (“relaxing”) a similar properly anchored up-down membrane is done via (a) a well defined mesh (b) a Physics Engine (i.e. Kangaroo2 [ the best GH add-on by 1M miles] available for GH by a certain Daniel P). Get the thing and try to get familiar with what it does - there’s some simple tensile mebrane examples available as well in the demos included.
BTW: In membranes and K2 ALWAYS separate the clothed edges from the naked ones and apply different spring values - as we do in real-life membrane designs. Google: tensile membrane anchor plates images … and study various contemporary proper anchoring plate designs > see the 2 mysterious cables going “along” the perimeter from plate to plate ?.
BTW: Not 100% the same with your goal … but since it’s a kind of “linear” solution is more or less 100% the same with regard the up-down anchoring policy:
Before Kangaroo2 (mesh is flat to the ground, all cables [and other things] waiting for the salvation):