Creating Mesh Features in Global Mapper Pro
Containing a robust toolset for 3D data viewing and editing, Global Mapper Pro also provides tools for users to generate 3D mesh features. Whether the starting point is a set of drone-collected images, point cloud data, an elevation model, or vector data, Global Mapper Pro can be used to create a complex vector mesh representing the area of interest. Once generated, mesh features can be visualized in Global Mapper’s 3D viewer, used to generate fly-through recordings, and exported to any supported format for sharing with colleagues or clients.
The Pixels to Points tool, available in Global Mapper Pro, creates 3D data from sets of drone or UAV collected images. Using the structure from motion analysis process, the Pixels to Points tool is able to turn sets of overlapping images into a complete and textured 3D mesh. The mesh features generated with this tool are textured with the drone-collected images to create a realistic model of the captured study area.
Using control points to boost positional accuracy of the generated data, Pixels to Points can be used by anyone with Global Mapper Pro to generate an ortho-image, point cloud, and 3D mesh from a set of geotagged images.
Global Mapper Pro contains a suite of tools specifically designed for point cloud editing and analysis. Alongside tools for rectification, filtering, and point classification, options to create a 3D mesh from a set of selected points and extract classified buildings as mesh features are found. Any point cloud, photogrammetric or lidar, can be used with these mesh creation methods, and the selection and filtering tools in Global Mapper Pro make it easy to select the specific set of points that will be used to generate the mesh.
Using only the selected points to create a detailed feature, the 3D mesh is textured with the RGB color values associated with the selected points. Like any 3D mesh, this created vector can be viewed in the top-down and 3D Viewers and exported to share.
While individual buildings can be created as 3D mesh features using the create a mesh from selected features option, the Lidar Feature Extraction tool provides an easier to use solution. Beginning with a classified point cloud, building features can be automatically extracted as 3D mesh models, or vector area features, for viewing, export, and analysis.
A digital elevation model is pixel-based 3D data that shows the topography of the desired area. With a simple data type conversion in Global Mapper Pro, raster elevation data can be vectorized as a 3D mesh. Accessed from the Layer menu, an option to Create Mesh from Terrain/Imagery creates a mesh feature from the desired terrain layers. Texture from a raster image layer can be applied to the 3D mesh in the creation process by electing to use an image and elevation model layer.
Since this created mesh is derived from an array of 3D pixels, the wireframe structure, able to be viewed in the top-down or 3D Viewer, is uniform. Options in the 3D mesh creation process can be applied to simplify the feature by a percent of the full-resolution size. A simplified mesh will retain the shape of the source data, but with fewer triangular faces it will create a smaller output file when exported to share.
While vector features in Global Mapper can carry feature elevations or per-vertex elevations making them 3D, an option to generate 3D mesh buffers can be found in the Digitizer tool. Like traditional buffers, 3D mesh buffers are created by adding a distance to a selected point, line, or area feature. With options to create cylindrical mesh buffers, spherical buffers, and pipe buffers depending on the vector feature types selected, points, lines, and areas can be enhanced with these volumetric features.
Assigned a buffer distance and other necessary parameters when created, volumetric mesh buffers are shown with a single color at a user-set level of opacity. Able to be viewed in the top-down and 3D views of Global Mapper Pro, mesh buffers prove to be a useful tool for feature visualization and analysis. More information on the different types of mesh buffers available in Global Mapper Pro can be found in this blog.
In addition to deriving 3D meshes from loaded terrain, point cloud, and vector data, Global Mapper can load and display mesh features. A particular use for this ability is the option to assign any point type a specific 3D mesh that will be used for the display in the 3D Viewer. Accessed through Global Mapper’s Configuration > Styles settings, point styles can be altered, and a 3D model can be chosen for 3D point display. Choosing from a library of built-in mesh models or uploading a custom 3D model, this use of 3D mesh objects enhances the visibility and meaning of point features when incorporated into fly-through recordings with other 3D data.
After creating any number of 3D mesh features in Global Mapper Pro, these layers can be exported to a variety of supported formats. Common in engineering disciplines are CAD formats like DXF and DWG that will preserve the shape of the mesh, but some other popular formats include 3DS, FBX, and OBJ. Of course, any data including 3D meshes can be exported to Global Mapper Package format for later use in the program or to share with other Global Mapper users.
Other methods to share created mesh features and any 3D data from Global Mapper include the creation of a visual fly-through video recording with the 3D Viewer or an export to 3D PDF.