OctObject Structure
struct octObject {
octObjectType type;
octId objectId;
union {
struct octFacet facet;
struct octInstance instance;
struct octProp prop;
struct octTerm term;
struct octNet net;
struct octBox box;
struct octPolygon polygon;
struct octCircle circle;
struct octPath path;
struct octLabel label;
struct octBag bag;
struct octLayer layer;
struct octPoint point;
struct octEdge Edge;
struct octChangeList changeList;
struct octChangeRecord changeRecord;
} contents;