Research On Technology Of Loading Automatically Adaptive Cartographic Symbols

The automatic adaptation of cartographic symbol is an important aspect of interaction between spatial information. The automatic adaptation of cartographic symbol can be divided into interactive adaptation between users and computers and automatic adaptation for the screen. The automatic adaptation of cartographic symbol can be applied to resources of oil and gas, traffic, educational, agricultural and forestry geographic information system and so forth. It is hotspot and difficulty in the research of map cartography. Based on the major project of Ministry of land and resources “Supporting information system for integration and management of oil and gas resources data”(project number 2009GYXQ24-01), which is carried out by China University of Geosciences( Beijing), this paper combines the thematic application of cartography for resources of oil & gas, and automatic adaption for the requirements of users and then discusses the theories and the realization of automatic adaptation of cartographic symbols.“The rapid mapping system for exploration and exploitation of oil & gas” is a subsystem of “The supporting information system for integration and management of oil and gas resources data”. The functions of the subsystem contains three aspects:Producing hanging charts for type of petroleum and natural gas resources; Producing atlas of national registration status of exploration and mining area of oil & natural gas,and the atlas comprise three kinds of basin, provinces and companies. In addition,counting spatial information and attribute information of oil and gas resources is also another function of the subsystem. “The rapid mapping system for exploration and exploitation of oil & gas” is an important embodiment of thematic mapping application for oil and gas resources, and it involves generating spatial data of map,configuration of map symbol, editing map, decoration of map, and query and counting of spatial data attribute data, etc.Loading automatically adaptive cartographic symbols for the resources of petroleum and natural gas is a vital functional module in the process of generating thethematic maps of oil & gas resources. The automatically loading of symbols involves two aspects which are adaptive loading of geometric cartographic symbols and adaptive loading of cartographic annotation symbols.1) Loading geometric map symbols, which is the adaptive collocation of point, line and polygon symbols including symbol size is in accordance with the map scale,loading range of symbols is adaptive to the map layout, color rendering is in accordance with the oil and gas industry standards and so on.2) Adaptive configuration of map annotation symbols, involving the positions for labels of point features are adaptive to the needs of human visual sense; positions for annotations of linear elements and areal features are adaptive to the range of these relevant elements; The three types of annotation in the respect of color rendering is to automatically achieve the users’ needs, as well as these three kinds of note distribution is to avoid confliction, so as to adaptively choose the best configuration location.This thesis does research on automatic adaptation of cartographic symbol, and realizes the transformation from the theoretic models of research on automatic adaptation of cartographic symbols to practice. It is an important embodiment of the interaction between geographic information in the field of resources of oil and natural gas.