A Hierachical Seamless Model of Spatial Data Based on QTM
Xuesheng Zhao · Journal of China University of Mining and Technology · 2008
A hierarchical seamless model for representing the global multi-resolution spatial data based on a quaternary triangular mesh(QTM) was constructed.The continuous quaternary code was used as index of QTMs and a transformation algorithm from quaternary code to longitude-latitude coordinates was developed based on its encoding rules.A vertex extension method of eliminating the cracks caused by different subdivisions was presented on the basis of not destroying the hierarchical characteristic of QTMs.The experiments and analysis are carried out with Wsiearth.tif image data in ArcGIS and GTOPO30 DEM data.The results show that the cracks in multi-resolution spatial data expression have been eliminated efficiently while the whole structure characteristic of QTM is maintained completely.