Navigation device, method of predicting a visibility of a triangular face in an electronic map view

A navigation device (1) for a vehicle (8) comprises a database (2a, 2b) storing, for a plurality of tiles of a tiling, at least one triangulated irregular network, TIN, defining a three-dimensional surface, and, for a plurality of triangular faces of the at least one TIN, control information defining a nested bounding sphere for the respective triangular faces. The navigation device (1) comprises further a processor (3) coupled to said database (2a, 2b), configured to calculate a screen-space error for the plurality of triangular faces based on the respective control information (16) and based on at least one of the following: a viewing angle of an electronic map view, a virtual camera position of the electronic map view. The processor is configured to predict whether a triangular face is visible in the electronic map view based on the calculated screen-space error.