The Buffer command creates a user specifiable buffer around the selected geometries. If the buffers around 2 distinct polygons overlap then only 1 polygon will be created. It is possible to create a buffer around a point or a line in which case a polygon will be created. When you select the Buffer command you will be asked to enter the size of the buffer in metres. It is valid to enter a negative buffer value.
How to use the Buffer tool
To explain how to use this tool we will be using prepared records:
- Rectangle (polygon)
- Square (polygon)
- Straight Line (line)
- Trapezium (polygon)
- Point (point)
We can add a buffer to any type of records (points, lines, polygons). In this example we will set a 2 kilometres buffer to a trapezium(number 4). Firstly, we need to select the trapezium. To do that we’ll use the Mark & Move tool.
Please pick the Mark & Move tool and click on the desired record.
Inspection mark will appear in that spot and all information about the record will be displayed in the Inspector panel. Now we are ready to start the editing process. Please click the Edit record button.
Clicking the Edit record button will change the selected record colour. It means that the record is currently in the Edit mode.
You can also select a record that you want to edit by using the Inspect tool. On the Inspected record list you can choose from which layer you want to edit a record in selected location. Then you can click Edit button to enter the Edit mode.
On the Key panel (left side) you can always check which layer is currently edited. Under the layer title you will see information “Currently edited layer”.
Records which are in Edit mode can be modified by all tools from the Modify Selected Geometries group. Because we want to set a buffer for the record we will pick a Buffer tool.
In the Buffer properties window you can set the buffer radius and pick one of the Unit type. In this example we will set a 2 kilometres buffer for selected trapezium. To confirm our settings we have to click OK button.
Now we will see a preview of the new (increased by buffer) geometry. Please click Save button to keep the new polygon or Cancel to dismiss all changes.
This is how the final geometry will look:
