Top New Features in Global Mapper v24.1
The newest “dot release” of Global Mapper contains new tools, additional functionality for existing features, and hot off-the-press bug fixes. The standard version of Global Mapper 24.1 brings a highly requested ability to create Relative Elevation Models, commonly used to highlight terrain variation in otherwise flat regions such as riverbeds, the ability to add 2D, 3D, or perpendicular perspective Inset Maps in the Map Layout Editor, expanded raster resampling methods.
Other minor updates include: the renaming of the Control Center’s right-click menu item from Edit Attributes to Layer Attributes in order to better fit its functionality, the addition of Fathoms as a Supported Depth Unit for terrain layers (1 fm = 6 feet), and the ability to crop off one or both ends of a line feature.
Here are three of the top new features in Global Mapper v24.1 standard. This blog is part two of two. Here is part one, where we cover the new features in the Pro version.
Adding to Global Mapper’s extensive terrain analysis tools, Relative Elevation Models can now be created with the new Create Relative Elevation Grid tool. Sometimes called River Elevation Models, they are used to highlight terrain variation relative to a line feature, such as near a river, or highway. These models help to visualize aspects of the terrain that may otherwise be hard to identify in imagery or a digital terrain model (DTM) by looking at local changes in elevation rather than comparing elevation to sea level.
Relative Elevation Models or REMs are created based on sampled elevation points along a linear feature (such as a river) in order to highlight the changes within the feature and/or the feature and the surrounding terrain. In the images below, compare a standard digital elevation model (Left) to a river elevation model (Right) of the same area. We know that rivers flow downhill, so a REM removes that trend from the data. They are useful for measuring the change in elevation as compared to the river, instead of comparing it to sea level.
Inset Maps can be added to maps in order to add a spatial reference or more information to the data displayed in the main map. You’ve likely seen them before as smaller, zoomed out, maps in the corner that help describe where in the world the main map is focused on. Global Mapper has taken this a step further in the Map Layout Editor. Inset maps can be created from the normal 2D viewer, and also from the 3D view or the Path Profile viewer.
Inset Map Elements in Global Mapper are static, not dynamic. Once they have been created in the Map layout Editor, they will not change when you change the original data. This means you don’t have to worry about accidentally altering the map while exploring the data. To update the map, right-click and find the Refresh checkbox in the Inset Maps’s Properties.
3D view inset maps will inherit the current perspective in the viewer when the inset map is created. This displays any vector or raster data that have elevation values. The options are as limitless as the 3D viewer itself. You can drape an image over an elevation layer to show what the land looks like, or add additional vector information to help the reader understand what’s important in the map.
This also applies to the path profile inset maps. Keep an eye on the scale of the path profile window itself (the height and width of the window). These changes affect the scale of the graph and how smooshed the data display appears to be in the tool, and that will be reflected in the inset map.
Adding to an existing feature, v24.1 includes a variety of new resampling methods for raster data including directional gradients, edge detection, and more. Found in Raster Options of both imagery and terrain data, these filters can be applied to a layer to highlight patterns or improve the display. This is a simplified version of a more powerful tool available in Global Mapper Pro, Apply Convolution Filter.
In the image below, compare an image with the Sobel Horizontal resampling method against the original. This filter uses weighted kernels to highlight horizontal patterns in the image. A kernel is a pattern of weighted values and zeros to ignore certain values in the kernel helps to emphasize patterns, depending on what cells are emphasized and by how much. See how the horizontal mountain features in the terrain and the river are more strongly displayed. Other filters in the tool can highlight patterns in specific cardinal directions, or sharpen the image to highlight small features.