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Showing posts from March, 2026

048] How to Partially Correct DEM Elevation in Global Mapper Using Terrain Paint

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Modify specific regions of your DEM using intuitive brush tools and feature-based selection. In this tutorial, we explore the Terrain Painting tool in Global Mapper, which allows for localized elevation edits. Unlike global corrections, this workflow enables you to smooth, raise, lower, or fix elevations for specific sites, such as construction platforms or road beds, while blending them naturally into the surrounding terrain using feathering techniques. In our last session, we covered how to correct an entire DEM layer. Today, we will learn how to modify only a specific area of your DEM data. Opening the Terrain Paint Tool in Global Mapper With your DEM data open: img 1 : Enable Terrain Painting icon in Global Mapper toolbar Click the Enable Terrain Painting menu. The Terrain Paint Options window will appear. img 2 : Terrain Paint Options window interface Terrain Paint Options Breakdown ...

047] How to Correct DEM Elevation Values in Global Mapper (Scale, Offset & Power)

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Adjust Digital Elevation Model (DEM) values using mathematical formulas to emphasize terrain features or normalize data. Although DEM elevation correction is not commonly required, it can be useful when you need to exaggerate terrain differences for visualization or design purposes. especially when maximizing elevation differences in flat contours for design purposes. This tutorial covers how to modify an entire layer using Scale Factors, Offsets, and Elevation Power, as well as how to manage valid elevation ranges and invalid data replacement. While it doesn't happen often, there are rare cases where you need to correct the elevation of DEM (Digital Elevation Model) data. This technique is especially useful when flat terrain appears visually weak and you want to emphasize elevation differences in maps or 3D terrain models. In Global Mapper, there are methods to correct DEM data by either adjusting the entire layer...

045] How to Create Shortest Path Lines from Points to Lines (Chainage Tool)

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Learn how to generate the shortest connecting segments between points and lines while automatically calculating chainage distances. This tutorial explores the "Chainage - Connect Selected Points to Selected Lines" feature in Global Mapper. We cover the initial setup, attribute configurations such as offsets and start points, and the process of displaying results using custom labels for technical documentation. Creating Shortest Path Lines Between Points and Lines This function can be used to measure how far a specific point is from a river or road in a straight line, to determine the distance of an intersection from the start or end of a road, or to identify the best location when branching water and sewage pipelines. Let's get started. First, draw some points and lines on your screen. img 1 : Initial points and lines drawn in Global Mapper Running the Cha...

046] How to Create Parallel Offset Lines in Global Mapper

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Learn how to generate multiple parallel offset lines from selected vector features at precise intervals. This tutorial demonstrates the dedicated parallel line creation tool in Global Mapper. We move beyond the old workaround of converting buffers to lines and explore the settings for spacing, directional orientation, and non-overlapping geometry to streamline your GIS drafting workflow. In this tutorial, we will learn how to create precise parallel offset lines in Global Mapper using the built-in Advanced Feature Creation tool. Previously, this specific feature was not available in Global Mapper. In the past, we had to draw buffer lines and then convert those buffers back into line features to achieve a similar result. Let’s get started. Creating Parallel Offset Lines in Global Mapper First, draw a line on the screen and select it. img 2 : Right-click menu showing Advanced Feature Creation Options R...

[052] How to Use Formula Calculation in Global Mapper Attribute Setup

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Automating attribute transformation using mathematical and string functions to prepare data for 3D modeling. This tutorial explains how to use the "Use Formula Calculation" feature within Global Mapper's Attribute Calculation Setup. We focus on a real-world scenario where elevation data is trapped inside a text string (e.g., "FH:118") and must be extracted and converted into a numeric attribute for accurate 3D simulations. Why Attribute Transformation Matters in 3D Simulation For 3D simulations, you need to create 3D data by applying a planned elevation to each parcel. However, in actual CAD drawings you receive, the parcels and the planned elevations are often placed on separate layers. Of course, if there are only one or two, you could manually enter the elevation value for each parcel, but if there are hundreds of parcels, the story changes. Take a look at the data below. img 1 : Global...

051] How to Automatically Detect Site Boundaries in Global Mapper Path Profiles Using ChatGPT

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Use exported coordinate data to automatically detect project site ranges in terrain profiles. This tutorial demonstrates how to leverage raw X, Y coordinate data from Global Mapper CSV exports to help ChatGPT automatically identify and highlight project site boundaries on a cross-section graph, eliminating the need for manual range input. Continuing from the last session, I had more conversations with ChatGPT. It really feels like talking to a human. The Problem with Manual Site Range Input In the previous post, I manually designated the "site" area. In other words: img 1 : Intersection of the profile line and the project site boundary in Global Mapper As shown in the image above, I manually identified the range where the cross-section line intersects with the project site boundary and input that range when ChatGPT generated the graph. Using CSV Coordinate Data for Automation However, look...

050] How to Create Advanced Terrain Profiles from Global Mapper Using ChatGPT

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Export raw elevation data from Global Mapper to CSV and use ChatGPT to generate professional, high-fidelity terrain cross-sections. This tutorial demonstrates how to overcome the visual limitations of built-in GIS profile tools. By leveraging AI-driven Python scripting, you can create custom-shaded site areas, highlight steep slopes, and add precise leader-line annotations to your terrain analysis reports. Exporting Path Profile Data from Global Mapper Today, I’d like to share an experimental workflow for improving terrain profile visualization in Global Mapper. First, please run Global Mapper. img 1 : DEM created in Global Mapper with a line segment added for profile analysis With the DEM created, add a line segment. Now, let's extract the terrain profile. img 2 : Accessing Path Profile through the Analysis/Measurement menu After selecting the line segment, right-click and select Anal...