“…Subsequently, the 2D PFEM has been extended to 3D PFEM [15,16]. 3D PFEM have been developed and implemented in various methods and fields, such as variable-element topology finite element method (VETFEM) [17], computer graphics [18][19][20], nonlinear continuum mechanics [21], electromagnetic simulations [22], boundary-element-based finite element methods (BEM-based FEM) [23,24], flow simulations, material design, and fracture [25].…”