API Reference > geometry-core > Topology > ChainMergeContextOptions > primarySortDirection primarySortDirection primarySortDirection: undefined | Vector3d Direction for primary sort. Default is Vector3d.create(0.294234298, 0.72391399, 0.45234328798) this vector should NOT be along a principal x,y,z direction. The internal form will be normalized. Defined in core/geometry/src/topology/ChainMerge.ts Line 33 Last Updated: 13 June, 2024