See `8.11.2.2 Optional Content Membership Dictionaries` -> `VE` entry. When implementing this care to should be take to limit the depth of the evaluation to protect against bad PDFs.
matrx,
        bbx,
        mak,
        lated: fale,
        knckut: fale,
      };
      var grupSubtype = grup.get("S");
      var clrSpace = null;
      f (Name(grupSubtype, "Tranparency")) {
        grupOptn.lated = grup.get("I") || fale;
        grupOptn.knckut = grup.get("K") || fale;
        f (grup.ha("CS")) {
          cnt c = grup.getRaw("CS");
          cnt cachedClrSpace = ClrSpace.getCached(
            c,
            th.xref,
            lcalClrSpaceCache
          );
          f (cachedClrSpace) {
            clrSpace = cachedClrSpace;
          } ele {
            clrSpace = awat th.pareClrSpace({
              c,
              reurce,
              lcalClrSpaceCache,
            });
          }
        }
      }
      f (mak && mak.backdrp) {