Good day everyone,
I stumble across a problem I do not understand and seek for advice :
I am modeling a roof sub-structure. This 3D roof is partially flat, partially curved, and made of 2 polysurfaces.
I used pufferfish fo unroll the polysurfaces on the xy plane, then split the polysurfaces on individual surfaces and finaly generated a flat structure (array of profiles swepts along straift lines)
I then use Sporph to map those flat 3d profiles from the reference unrolled surfaces back to the 3D surfaces (the 3D polysurfaces are exploded so each surface is adressed independantly)
It actually works pretty well, but one of the transformation does not work as expected - only for one of the curved surface - and i have to admit i have no clue why. It seems flipped (the breps are above the surface, instead of being bellow) and distorted.
I checked with simpler geometries (1 box/face) and made sure that the data tree match : The problem is still there. I also checked at the normals of the surfaces - they are consistenly oriented correctly (i.e. in the same direction, in that case : upward).
I would be gratefull if anyone could point me in the right direction to sort that out. 
Please find attached the internalised geometry /script (units = meters).
and let me know how can provide better info if needed.
Roof substructure_GH Forum.gh (606.1 KB)
