Creating Mesh Buffer Features in Global Mapper Pro
As the prevalence of 3D data expands, GIS professionals find themselves needing to create 3D features to better model and visualize new projects and plans in 3D. In the latest edition of Global Mapper Pro, version 23.1, the ability to generate volumetric mesh buffers provides an easy way to create new three-dimensional features in a workspace.
Like traditional, two-dimensional buffers, the creation of volumetric buffer features is based on existing vector points, lines, and polygons. These generated 3D features are vector meshes that can be visualized and used in Global Mapper or exported to any supported format to share with colleagues or clients.
The creation of mesh buffers of various types can be used to plan the implementation of utility infrastructure or the scope of new construction projects. In this example, a new housing development is being planned, and mesh buffers are used to represent and model buried utility lines or water mains, hydrant effective areas, and approximate building sizes.
Three-dimensional pipe features can be created from existing lines to model a myriad of infrastructure components, including buried utility lines and water or sewer mains. Beginning with a set of simple lines representing the path of the buried utilities, elevations are added and updated based on the loaded digital elevation model to provide three-dimensional line features as the basis for the mesh buffer creation.
After selecting the vector line features, the creation of pipe mesh buffers is initiated using the Volumetric Features option found in the digitizer menu. In the buffer creation dialog box, a radius is entered, the color and transparency of the mesh are set, and the created features appear in a new layer in Global Mapper. In the top-down view, the mesh buffers appear as a wireframe, representing their three-dimensional structure. In the 3D Viewer, these features appear semi-transparent and follow the elevations specified by the original vector line features.
Created only from point features, spherical mesh buffers use the selected point as the center of the sphere. Useful for modeling an impact area or effective radius, this type of mesh buffer is used in the development model to show the effective range of each fire hydrant.
Using the digitizer to select the point features that represent the proposed hydrant locations, spherical mesh buffers are created based on an entered radius, and the option to clip or crop the generated buffers below the terrain is enabled since the hydrant reach does not extend below ground.
Cylindrical mesh buffers can be generated in Global Mapper Pro from any vector feature type: points, lines, or areas. Similar to traditional vector buffers, these features add a distance to the edge of the selected feature. However, in the case of cylindrical buffers, the resulting area is extruded to a specified height in the form of a 3D mesh.
In the housing development plan, area features have been created for the building plots. The vector areas representing the plots work well to describe the layout in a top-down view, but when viewing this data in Global Mapper’s 3D Viewer, cylindrical buffers can be used to visualize the approximate space each house might occupy.
Selecting the two-dimensional polygons, cylindrical buffers with a distance of 5 meters and a height of 30 meters are created in Global Mapper. From the top-down view, the created mesh buffers appear as traditional two-dimensional buffer features, but when opened in the 3D viewer, they show the maximum 3D coverage of a house structure in this development.