Layered manufacturing (LM) is emerging as a new technology that enables fabrication of three dimensional heterogeneous objects (such as Multi-materials and Functionally Gradient Materials). The steps for fabricating heterogeneous objects include model representation and material process planning. This paper introduces a method for processing the material information. It includes pre-processing (discretization), orientation (build direction selection), and adaptive slicing of heterogeneous objects. The discretization process converts all material information inside a heterogeneous object to material features like geometric features, thus it makes it possible to determine build direction by estimating build time based on geometric features and material features. It also allows adaptive slicing of heterogeneous objects to minimize surface finish and material resolution error. In addition, tool path planning can be simplified to fill pattern generation. Examples are shown.