  Digital representations targeting design and simulation for Additive
Manufacturing (AM) are addressed from the perspective of Computer Aided
Geometric Design. We discuss the feasibility for multi-material AM for B-rep
based CAD, STL, sculptured triangles as well as trimmed and block-structured
trivariate locally refined spline representations. The trivariate spline
representations support Isogeometric Analysis (IGA), and topology structures
supporting these for CAD, IGA and AM are outlined. The ideas of (Truncated)
Hierarchical B-splines, T-splines and LR B-splines are outlined and the
approaches are compared. An example from the EC H2020 Factories of the Future
Research and Innovation Actions CAxMan illustrates both trimmed and
block-structured spline representations for IGA and AM.
