006] Global Mapper - Creating Buffer Lines (Create Buffer)
Today, we will learn how to draw Buffer Lines, which create a specific distance range based on points, lines, or areas (polygons).
"Before we begin, if you missed the previous session, check it out here:"
005] Global Mapper - Viewshed Analysis
▲ Learn how to perform professional Buffer Analysis in Global Mapper!
1. Preparing Your Workspace
We will continue using the workspace from our previous session. First, let's clean up some unnecessary layers.
Selecting 'Line' and 'Viewshed Analysis' layers in the Control Center]
Select the 'Line' and 'Viewshed Analysis' layers in the
Control Center while holding the Ctrl key. Both
layers will be selected.
Click the Close Layer (X icon) at the top right of the
Control Center to delete them. (Alternatively, you can press the
Delete key after selection.)
Your screen should now look like this, with the elevation data ready for the next steps.
2. Loading Satellite Imagery (Review)
Before drawing buffer lines, let's review how to load online data. We will fetch a satellite image that matches the size of our current terrain.
Click the Connect to Online Data icon on the toolbar.
When the Online Data window opens:
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Navigate to IMAGERY -> World Imagery.
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Click Draw Box to specify the download area.
When the 'Drag a Box to Select Export Bounds' window appears, draw a rectangle over the desired area and click OK.
Back in the main window, click Connect.
Now, the 'World Imagery' layer is added to the Control Center, and the satellite image is displayed on the main screen.
3. Drawing a Polygon Feature
Next, let's draw a polygon to serve as the base for our buffer.
Right-click on the main screen.
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Go to Create Area/Polygon Features -> Area -> Create New Area Feature.
The mouse cursor will change.
Draw a rough polygon as shown in the image below. Click points 1 through 7 with the left mouse button, and then right-click at the final point to complete the shape.
The Modify Feature Info window will pop up once the polygon is closed. Under the Feature Layer field, type "Area Boundary" (or your preferred name) and click OK.
The 'Area Boundary' layer is added, and your polygon is now visible on the main screen.
4. Creating Buffer Zones
Now, let's add the buffer lines. Select the polygon you just drew, right-click, and navigate to Create Area/Polygon Features -> BUFFER.
The Buffer Area Creation Setup window will appear.
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Feature Layer: Enter "Buffer Zone" for the new layer name.
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Number of Buffer Zones for Each Feature: Enter 4.
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Buffer Distance: Enter 500 and set the unit to meters.
This setting means we will create 4 buffer lines at 500m intervals. Click OK when finished.
The 'Buffer Zone' layer is created, and the buffer lines are drawn on the main screen.
5. Adjusting Transparency and Style
In newer versions of Global Mapper, created polygons are often filled with a solid color by default, which can obscure the underlying layers. Let's make the buffer lines transparent and change their style so the satellite image is visible.
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In the Control Center, select the 'Buffer Zone' layer.
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Right-click and select Options (or double-click the layer).
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When the Vector Options window opens, go to the Area Styles tab.
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Select Use Same Style for All Features and click Select Style.
In the Select Area Style window:
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Fill Pattern: Select No Fill (this removes the solid color).
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Border Style: Select Dot (this changes the line to a dotted style).
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Color: Click the color button and choose Yellow (for high visibility).
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Width: Set to 3 pixels.
Click OK on all windows to apply the changes.
As you can see, the buffer lines are now beautifully drawn over the satellite imagery!
Conclusion
This guide covers the most basic method of creating buffers. The Buffer Area Creation Setup window offers many other options for advanced spatial analysis.
That's it for today!
"In the next session, we'll dive deeper into more advanced features. Stay tuned!"
007] Global Mapper - Viewshed Analysis Including Buildings (Obstructions from Vector Data)
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