Research Of Implemental Methods On Three Dimensional Terrain Modeling

With social process, scientific development and eslation of economy, epoch of information has bee taking it's stride to us The human being has been living on global and reacting with surface global everywhere.For example, engineers explore and design surface of terrain and ruct building, geologists research ruction of terrain and ecogeologists are eager to research global state and the process of the earth material's generationing, while the workers measuring explore variety of terrain profile and describe shape of the earth with a mass of means.Although fields of research are different, aspects of research are various, all work is to be hope to display real terrain's image with convenient and accurate means.Digital elevation model is applied widely in geological information sysytem.lt is, for example, important data model; and it is also basic data matching with cruise flight vehicle's.ln the matching process of cruise fling vehicle's terrain, the height of flight vehicle continuely measures value of relative height of the flight vehicle with the ground . the data is inputed as Cull the observation in the filter, and it is compared standard digitial elevation modeling installed beforehand in the flight vehicle model with state equation of the flight vehicle equation to estimate current space position of the flight vehicle. What type is Choosed to match with it , so that the flight obtains more information and causes smallest different meaning by far; and it is the so-called choice question of match terrain.The DEM employed broadly; and numeral the earth, the digital city and the digital area and so on , the work as well as the virtual reality on three dimensional visible all needs the high accuracy stucture of the DEM.Presently, geographic information system basing on the really three dimension realization still has the technical difficulties which are not yet solved. In the first place, gathering on spatial three dimensional data , which is expensive on cost, is big and on space data quantity , is various type, is complex on sturcture; among situs relations of spot , line , surface and...