This paper introduces a new method that uses slice geometry to compute the Global Visibility Map (GVM). Global Visibility Mapping is a fundamentally important process that extracts geometric information about an object which can be used to solve hard problems; for example, the setup and process planning in CNC machining. In this work, we present a method for creating the GVM from slice data of polyhedron models, and then show how it can help determine around which axis of rotation a part can be machined. There have been various methods of calculating the GVM to date, tracing back to the well-known seminal methods that use Gaussian Mapping. Compared to the considerable amount of work in this field, the proposed method has an advantage of starting from feature-free models, like STL files. Also, it has solutions of adjustable resolution. Moreover, since it is built upon slicing the model, the method is embarrassingly parallelizable in nature, thus suitable for high performance computing. Using the GVM obtained by this method, we generate an axis of rotation map to facilitate the setup planning for 4-axis CNC milling machines as one implementation example.