Merge

This tool will execute merge command. Merging is the process of combining a group of polygons into the smallest number of polygon that represent the same topological area. In other words if two polygons that touch or overlap are merged a single polygon will be created that covers the same area.

How to use the Merge tool

To explain how to use this tool we will be using prepared records:

1. Rectangle (polygon)
2. Square (polygon)
3. Straight Line (line)
4. Trapezium (polygon)
5. Point (point)

Firstly, we need to move one of them so it will overlap with other geometry. To do that we’ll use the Shift tool. For a full Shift tool usage guide please visit: Shift

This is how the example records will look:

In this example we will use Merge tool to merge Rectangle (number 1) with Square (number 2). We need to select one of them. To do that we’ll use the Mark & Move tool.

Please pick the Mark & Move tool and click on one of the merged records.

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.

Records which are in Edit mode can be modified by all tools from the Modify Selected Geometries group. Before we will be able to merge both geometries we need to mark the 2nd geometry (Square). To do so, we will use the Clone tool.

Please pick the Clone tool and click on the other geometry.

Inspection mark will appear in that spot and all information about the other record will be displayed in the Inspector panel. There is one main difference in the Inspector panel. The Edit record button has been replaced by a Clone record button.

Please click the Clone record button to mark the second geometry.

Now both geometries are in Edit mode. As you can see, the Merge tool become available.

Our next step is clicking the Mark & Move button (its necessary to reset the right panel). Now please click Merge button.

Both geometries will change their colour to dark blue. It means that these two geometries will be merged. Please click Save button ('Edited record' tab) to keep the new polygon or Cancel to dismiss all changes.

The Merge operation is completed. This is how the effect looks (in this example):

As you can see inspecting the merged geometry will display 2 records. The first record is a new geometry created from the 2 previously separated records. The second one (Square) is the old cloned record which remained unchanged.

The second record (Square) can be deleted now. You can do this by clicking the delete button on the right panel (while inspecting the cloned geometry). This is how final version of merged geometry will look after deleting the old geometry: