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Digital information technology has made human beings move into a mixed space where virtuality and reality are integrated. Maps, that have always been used as the abstraction and interpretation of the real world and assist us to cognize the real world, are facing new challenges. Under the new digital and communication situations, maps need to incorporated digital virtual spaces and analyze the impacts brought by virtuality and reality, nihility and existence and the interpromotion of void and solid. Game maps are suitable carrier in this paper to analyze and discover the relations between the virtuality and the reality. Game map has seven elements including the time, the place, the personage, the object, the event, the phenomenon and the scenario to describe the world. This paper analyzes their virtual and real characteristics, explores the relationships and the interactions between virtual world construction and the reality, and discusses their feedback to the real world. This research can enrich the theoretical system of cartography and facilitate planning a smarter and more pleasant society for us. [ABSTRACT FROM AUTHOR]

Objects: Micro landform is an important basis for safe operation of transmission lines engineering, the risk division of lines icing and the calculation of energy consumption during the construction period of transmission lines. As the national grid extends and voltage levels increases, there are a lot of transmission lines passing through the micro landform area and damaged seriously. The traditional macro geomorphologic map can not show the micro landform characteristics accurately. It is subjective and costly for identifying micro landform by experts on the spot base on aerial photography and satellite images. Furthermore, it is difficult to meet actual engineering requirements. The automatic extraction micro landform of transmission lines is not only a requirement for digital transmission lines landform analysis precisely, but also a prerequisite and guarantee for the construction of power grid projects under complex landform conditions. Methods: According to the classification system of micro landform in the specifications, the micro landform types of transmission lines were investigated and five micro landform types including yakou, mountain, uplift, canyon and vapor were proposed. The micro landform type with yakou, mountain, uplift, canyon focuses on regional terrain complexity and relief, as while vapour landform focuses on the causes of the disaster. A decision-making scheme was proposed by terrain position index, slope, relative elevation and water distance, and a method of transmission line micro landform extraction based on grid digital elevation model(DEM) was constructed. About the vapor landform, the water distribution data were applied to the experimental area, the water area units were divided, and water body distance was calculated by grid statistics.Results: 9 transmission lines DEM data of a power grid company during 2012—2018 were used for extraction experiment. The micro landform type of yakou, mountain, uplift, canyon and vapor was extracted effectively, the position and tendency of the micro landform could be discriminated by the extraction results, and the statistical parameters of each transmission lines micro landform in the experimental area were obtained. A comparative analysis of disaster data form the influence of micro landform was added. It was found that the proportion of typical micro landform area where the disaster occurred was over 90%, much higher than the proportion of micro landform in the non-disaster area.Conclusions: The topographic position index, slope, relative elevation and water body distance were adopted to describe the five typical micro landform characteristics of the transmission line with digital terrain analysis technology and the existing transmission line micro landform classification system. Mined the micro landform information, a micro landform extraction method of grid DEM for transmission line was established. Compared with the traditional manual sketching method, it is simple and efficient, and the boundary contour of the extraction results was obvious, which could provide basic support for transmission line construction. [ABSTRACT FROM AUTHOR]