Editing difficult geometries

The majority of the time editing geometries in Alloy can be done within the Alloy interface. On a rare occasion an individual feature’s geometry will need to be digitised using specific curves, snapped to other features (held elsewhere) or require other manipulation.

Alloy and QGIS work well together.

In QGIS open a blank map (in EPSG:3857).

In Alloy select your item, navigate to geometry, click on the mini map and copy the GeoJson text on the right-hand side. (tip: click in the box and press Ctrl A then Ctrl C)

Back to QGIS click edit, paste feature as temporary scratch layer.

The shape of the Alloy item will be displayed as a feature in QGIS. All the tools and features can be used on the feature.

After your edits select your item in QGIS open the Python Console and enter the below command.

iface.activeLayer().selectedFeatures()[0].geometry().asJson()

Copy the response between the ‘’. In Alloy clear the geometry then click edit and paste the data.

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Alloy_QGIS

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