This tool gives a possibility of joining, splitting and merging polygons. There are three options (ways) that could be used to draw the lines: Joining, Splitting and Merging.
Please note: You can use two ways of drawing a line. One by placing nodes on the map with the left mouse button at specified location and another one which allows you to draw a line by holding a ‘Shift’ keyboard button. |
Joining is used to connect a piece of one polygon to another with one action.
In order for this method to take place, the line has to start and end at polygon that will be extended, while marking the area that should be cut out from diminished polygon.
The The following example shows how the part from Walpole (purple) joins the Ethorne (beige) polygon. The line starts from Elthorne polygon, marks the part of Walpole polygon that should be cut out and then goes back to Ethorne polygon.
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| Joining – drawing | Joining – result |
Splitting gives a possibility to divide a polygon into two parts.
The dividing line must pass through the given polygon and must go beyond its borders. The beginning and the end of the line lies outside the boundaries of the divided polygon. This method will take place, when the line passes through 3 polygons (areas), see Fig. 3
The following example shows how the Walpole polygon is divided into two parts. The drawing starts from Elthorne polygon, then goes through Walpole and finishes on Northfield polygon.
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| Splitting – drawing | Splitting – result |
Merging is used to connect two polygons into one.
This method will be activated by drawing single line through boundary of two polygons. It doesn't matter from which polygon the line starts, in both cases the smaller polygon will be connected to a larger one. The following example shows how the Elthorne Walpole polygon could be connected to larger Northfield polygon.Elthorne polygon.
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| Merging – drawing | Merging – result |
In order to roll the changes back, please use the following options:
- ‘Revert’ tool that is rolling back all the made changes in the current map.
- ‘Undo’ tool is used to return the state of the map before the last change.
In the unlikely event of reshaping a ward in a way that it now overlaps the neighbouring local authority, you can use the Trim function to automatically dispose of the unwanted overlap.
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| Trim - before | Trim - result |
