Union Mode

Union Mode allows you to merge multiple polygons into a single polygon. The original features will be replaced with the resulting union feature.

You can handle Union Mode for all layers on a map like this:

map.gm.enableMode('edit', 'union');
map.gm.disableMode('edit', 'union');
map.gm.toggleMode('edit', 'union');
map.gm.isModeEnabled('edit', 'union');

The following methods are available on map.gm:

Method	Returns	Description
`enableMode('edit', 'union')`	-	Enables global Union Mode.
`disableMode('edit', 'union')`	-	Disables global Union Mode.
`toggleMode('edit', 'union')`	-	Toggles global Union Mode.
`isModeEnabled('edit', 'union')`	`Boolean`	Returns `true` if global Union Mode is enabled. `false` when disabled.

The following events are available on a map instance:

Event	Params	Description	Output
`gm:union`	`event`	Fired during the union operation.	`map`, `originalFeatures`, `feature`
`gm:create`	`event`	Fired during the union operation.	`map`, `feature`, `shape`

The following events are available on a map instance:

Event	Params	Description	Output
`gm:globalunionmodetoggled`	`event`	Fired when Union Mode is toggled.	`enabled`, `map`

You can also listen to specific Union Mode events on the map instance like this:

map.on('gm:globalunionmodetoggled', (event) => {
  console.log(event);
});

Behavior

Union mode operates by:

Union mode supports the following feature types: