Terrain Generation Using GSI Tiles

When generating a new terrain in UC-win/Road, it is possible to use the GSI tiles published by the GSI. Users can import the GSI tiles of any area on map together with a set of aerial photographs and map images to construct a VR space. Since the terrain generated from the GSI tiles has the information of plane rectangular coordinates and longitude and latitude, materials can be placed and generated at the correct location even when other GIS data is loaded on the terrain.

In addition to the GSI tiles, a lot of topographical information such as SRTM is available as open data. By reading elevation data file formats represented by GeoTIFF, it is possible to generate the topography of any location in the world, including Japan.

Import 3D City Models

■Import PLATEAU open data models

By using 3D models such as "3DBD Viewer^*1" published by The National Institute of Advanced Industrial Science and Technology and "PLATEAU^*2" published by the Ministry of Land, Infrastructure, Transport and Tourism (MLIT), it is possible to reproduce urban landscapes as a single model. Buildings, terrain, plantings, and roadside facilities are compiled as 3D models by area, which can be loaded into UC-win/Road via general-purpose 3D model formats such as FBX. In PLATEAU, more and more building models of major cities in Japan are being available, and they are published with not only building shapes but also various attribute information such as the number of floors and the use of buildings. UC-win/Road will soon be able to import the building models including attribute information from PLATEAU.

■Import Zenrin 3D Map Data

In addition to open data, 3D city models provided by paid services can also be used in the same way. The "Zenrin 3D Map Data Online Service" by ZENRIN CO., LTD. provides 3D models that include not only buildings but also all the elements that make up the urban landscape, such as roads, road signs, power poles, and roadside trees. By specifying a variety of formats such as FBX, 3DS, etc., it is possible to download a vast range of model data and load it into UC-win/Road.

For the city models in PLATEAU and Zenrin 3D map data, the 3D models themselves have the coordinate values of the world geodetic system based on the plane rectangular coordinates, so after placing the model in UC-win/Road, setting the input value of X-Y coordinates (global coordinates) to 0,0 will place the model in the correct position in space.

However, open data does not always have accurate coordinate information. In this case, you can check the origin position of the 3D model on the FBX model editing screen, and then adjust the position by comparing with the coordinates and longitude and latitude of the origin position using the GSI's map information. If you do not require much accuracy, you can also adjust the position according to the aerial photograph.

Create Roads Using OpenStreetMap

OpenStreetMap allows you to download the geographic information on the map as open data and automatically generate road alignments by reading the downloaded osm file. If the topography of the data you are creating is generated based on accurate coordinate information such as the GSI 50m mesh topography or GSI tiles, it will be generated at the correct position without adjusting the coordinates.

Road alignments can be converted to LandXML format as well as being generated directly, so that linear information can be read by setting offsets even for terrain that does not have precise coordinates.

Create Building Using OpenStreetMap and Shape Files

Building information from OpenStreetMap can be read in UC-win/Road by using the "Download Features" function in the "Zone Editing" to generate a wide range of building shapes automatically. The area of creation can be specified freely in the UC-win/Road space. No troublesome operations are required since the building height information is also reflected.

In addition, the names of major buildings are automatically entered. Unlike 3D city models such as PLATEAU, the buildings themselves are generated in a single color, but you can select individual buildings and apply textures to them. Compared to placing buildings from RoadDB, the impact on performance is minimal even when generating buildings in a wide range thanks to their simple shape.

Even in areas where no building information is provided in OpenStreetMap, buildings can be generated and imported in UC-win/Road using the Fundamental Geospatial Data, by converting the building external shape information via the Fundamental Geospatial Data viewer into the Shape file format. When generating buildings from Shape file, uniform texture can be applied to the sides and top in the setting.

Merge Terrains Using Shape and IFC Files

As well as generating buildings, you can export the topographic information from the Fundamental Geospatial Data to a Shape file and combine it with the terrain you have already created. For example, if you want to improve the accuracy of part of a 50m mesh topography, you can convert the required area to a 10m or 5m mesh topography provided by the Fundamental Geospatial Data. IFC files can also be used in the same way, and the topography used in the design can be reflected.

Import Point Cloud Data

By importing point cloud data measured by MMS or 3D laser scanners, it is possible to create landscape representations and road structures based on point clouds, and it is also possible to convert point clouds into terrain patches to reproduce the undulations of the ground surface in detail. The point cloud can be in any general-purpose format, such as asc, csv, dat, or las, and color information of the point cloud data can also be imported. Even if the data does not have color information, it can be colored later using aerial photographs. Recently, more and more municipalities are publishing point cloud data files of their region as open data. For example, on "MLIT's Data Platform*3" and "Shizuoka Point Cloud Database*4", you can view and download a variety of point cloud data such as roads and facilities and use those data in UC-win/Road.

Fig.7 Input of road alignment based on point cloud

licenseCC BY 4.0　from Shizuoka Point Cloud Database　termshttps://pointcloud.pref.shizuoka.jp/terms

^*1　3DDB Viewer　https://www.airc.aist.go.jp/gsrt/3ddb-viewer.html

^*2　PLATEAU　https://www.mlit.go.jp/plateau/

^*3　MLIT Data Platform　https://www.mlit-data.jp/platform/

^*4　Shizuoka Point Cloud Database　https://pointcloud.pref.shizuoka.jp/