### **MeshDual** * * * * * **Description**： This component computes the dual graph of a mesh. **Input**： Mesh: Input a mesh. withBoundary: Whether you want to create a dual graph with boundary or not. **Output**： Polyline: Return a polyline list as a dual graph. Ngon: Return a ngon list as a dual graph. **Algorithm Details**： Sometimes, we use it for designing building's curtain walls. The edge count of a polygon depends on its center point, which is a vertex from your original mesh. For example, if that vertex's valence is 6 (means this vertex is shared by 6 triangles) , you will get a hexagon though MeshDual. So, if you have a uniform triangular mesh (Every vertex valence is close to 6), you will get many hexagon polylines via this algorithm. However, if you input a quadrilateral mesh, you will get a new set of quadrilateral polylines, which are generated by interconnecting the center points of original quadrilateral mesh faces.