split comp operation by "planar surfaces"?
Hi All
I posted a Suggestion in the Idea section,
comp operation by "flat island" in CityEngine
but I thought maybe there is a way to do just that already and I haven't thought about it.
If you ppl have some sugestions it would be amazing! And if you like the suggestion please vote for it 
so it maybe gets implemented.
It is a problem I encounter all the times, as I work with imported FBX assets, lots created from curved streets, L, U and O shapes, so very irregular base shapes.
My question:
Is there a way to do a 
comp split that separates objects into "islands", or "flat shells" as long as they are continuous, so if the angle between faces does not exceed a certain amount. Independently from the number of faces this "island" contains.
Take this example, where bot the C faces and A faces are orientated in the same way, let's say parallel to the object front, while the B faces are at 70 degrees .
comp(f) { front= X} would produce a single mesh composed of A and C, thus not creating a flat surface.
comp(f) { front: X} will create 18 separates faces (12 in A plus 6 in B)
I suggest adding a comp(i) operation so that writing
comp(i) { front: X} produces 2 separated meshes, A and C.
I think it could be very useful especially with the buildings created from L, U and O shapes.
There could be an extra parameter defining what is the angle between faces in degree that is the limit to consider a shell "flat", like a threshold parameter. So that if there is an angle of 3 degrees between 2 faces and I type "4" in this parameter, the 2 faces will still be considered as part of the same shell.
ALTERNATIVELY
If this is not possible, is there any method, taking the above example, AFTER doing
comp(f) { front= X}
therefore eliminating surface B, to separate surface A from Surface C without splitting them into 18 microfacets?
UPDATE I see there is a function called geometry.isPlanar, maybe something involving that.. 😕
Thanks!
Ideally it is two different separsed problems:
- separating surfaces into shells accordingly to their normals independently by the number of faces.
- splitting geometries by continuity, like the 2 front faces of a O shaped building (external front and internal front) independently by the number of faces.
Having these two extra operations should cover all situations 
Bump
