Summary
In ArcGIS Pro, buffer polygons can be created using the Buffer tool to generate an area of effect surrounding a point feature for analysis. However, the Buffer tool creates an additional polygon feature layer on the map. In a scenario where additional features are not required, the ring symbology can be used to create an area of effect surrounding a point feature. This article describes the workflow to symbolize point features with two rings. The symbology emulates the effect of the Buffer tool while maintaining a single point feature layer on the map.
Procedure
- Change the project’s units to millimeter in ArcGIS Pro.
- In ArcGIS Pro, navigate to Project and click Options.
- In the Options window, click Units.
- Select and expand 2D Symbol Display Units.
- Check the Millimeter option. Click OK.
- Create the first ring symbology surrounding the point features.
- In the Contents pane, double-click the symbol of the layer to expand the Symbology pane.
- In the Symbology pane, under Properties, click Layers .
- Under Layers, expand Appearance.
- Under Appearance, click Form and select the filled circle.
- Click the Shape fill symbol drop-down button, under Polygon symbols, select Outline only (0.1 pt).
- Select an outline color and set an appropriate value for Outline width. This workflow uses 0.25mm as an example.
- In the Symbology pane, click the Menu icon and click Allow symbol property connections.
- Under Appearance > Size, click the No attribute mapping defined icon .
- In the Set Attribute Mapping window, click the Set an expression icon to expand the Expression Builder pane.
- In the Expression Builder pane, in the Expression text box, enter the following expression. In this example, the circle size used is 500,000 mm. Click OK.
<circle size in mm> / $view.scale * 2.83465
- Create a duplicate of the ring symbology created in Step 2 and resize it.
- In the Symbology pane, under Properties, click the Structure icon .
- Under Layers, click the Duplicate layer icon to duplicate the symbol layer.
- In the Symbology pane, under Properties, click Layers.
- Change the duplicated layer’s size expression. Repeat steps 2(i) and 2(j).
- In the Expression Builder pane, in the Expression text box, enter the following expression. In this example, the circle size used is 1,000,000 mm. Click OK.
1000000 / $view.scale * 2.83465
- In the Symbology pane, click Apply.
The following image shows the two rings created on each point feature.