3D road models are widely used in many computer applications such as racing games and driving simulations. However,
almost all high-fidelity 3D road models were generated manually by professional artists at the expense of intensive labor.
There are very few existing methods for automatically generating 3D high-fidelity road networks, especially for those
existing in the real world. Real road network contains various elements such as road segments, road intersections and
traffic interchanges. Among them, traffic interchanges present the most challenges to model due to their complexity and
the lack of height information (vertical position) of traffic interchanges in existing road GIS data. This paper proposes a
novel approach that can automatically produce 3D high-fidelity road network models, including traffic interchange
models, from real 2D road GIS data that mainly contain road centerline information. The proposed method consists of
several steps. The raw road GIS data are first preprocessed to extract road network topology, merge redundant links, and
classify road types. Then overlapped points in the interchanges are detected and their elevations are determined based on
a set of level estimation rules. Parametric representations of the road centerlines are then generated through link
segmentation and fitting, and they have the advantages of arbitrary levels of detail with reduced memory usage. Finally a
set of civil engineering rules for road design (e.g., cross slope, superelevation) are selected and used to generate realistic
road surfaces. In addition to traffic interchange modeling, the proposed method also applies to other more general road
elements. Preliminary results show that the proposed method is highly effective and useful in many applications.