Study on Key Techniques for Multi-scale Expression of Laneway Traverse Data in MGIS

The multi-scale expression of enormously complicated laneway data requires differentiation of both contents and the way the contents are expressed. To accomplish multi-scale expression laneway data must support multi-scale transformation and have consistent topological relationships. Although the laneway data generated by traverse surveying is non-scale data it is still impossible to construct a multi-scale spatial database directly from it. In this paper an algorithm is presented to first calculate the laneway mid-line to support multi-scale transformation; then to express topological relationships arising from the data structure; and, finally, a laneway spatial database is built and multi-scale expression is achieved using components GIS-SuperMap Objects. The research result is of great significance for improving the efficiency of laneway data storage and updating, for ensuring consistency of laneway data expression and for extending the potential value of a mine spatial database.