| Abstract [eng] |
Terrain rendering is used in geodesy, geographic information systems, computer games and other fields. Usually measured terrain data isn’t sufficiently precise, and if used for rendering, the result looks unnatural. This paper analyzes three main topographic data sources of planet Earth, that are publicly available: GTOP30, ASTER GDEM and SRTM. It compares the most often used methods for terrain data: bilinear, bicubic, inverse distance weighted and natural neighbor interpolation. To monitor SRTM data interactively an ArcGrid Viewer tool was created. It can be used to see terrain files in ArcGrid format. To study interpolation methods, a separate GeoSG tool was created. It can display several terrains at once and interpolate terrain data using bilinear, bicubic, inverse distance weighted and natural neighbor methods. This tool is used to evaluate interpolation methods. Results showed, that the best method for interpolation is the bicubic interpolation method, the worst – inverse distance weighted interpolation method. |
