Find central ploygon

Hi Ricky,

Our team worked on it but is having a hard time getting it to work. Do you have sample code for Bing Maps?

We do not need the exact center of the polygon, but approximately near the center.

Thanks!

If not already, I'd start by converting your data to GeoJSON using the GeoJSON module, or ahead of time. This will make a lot of open source libraries easy to use and make a migration to Azure Maps in the future easier.

The solutions I provided in the sample here https://rbrundritt.azurewebsites.net/Demos/AzureMaps/PolygonCollectionCenter/index.html are based on GeoJSON, and simply put the results on Azure Maps. So reusing the main solution should be as easy as converting the your data to GeoJSON, then converting the resulting GeoJSON back to Bing Maps shapes. Start off by loading the required libraries if you are using one of the Turf or polylabel solutions. You can download a browser friendly version of polylabel here: Download polylabel for the browser here: https://github.com/mapbox/polylabel/files/6552548/polylabel.zip

Here is a Bing Maps version of the code sample: https://rbrundritt.azurewebsites.net/Demos/BingMaps/PolygonCollectionCenter/

Hi Ricky,

Thank you for your response, and sorry to bother you again.

As we read data using the API and plot it on the map, the polygon collection in the format shown below, which we cannot convert into GeoJSON.

Is there a way to find the center from the polygon collection.

Thanks

Since you are starting with Bing Maps shapes, you can still convert them to GeoJSON. The GeoJSON write method is meant to convert a single shape. So you can loop through your data to create a feature collection. If you want to be able to get the original polygon after all the calculations, you can capture the ID of the polygon when converting that to GeoJSON, then use that later to look up the polygon you want. Here is a code sample:

var shapes = layer.getPrimitives();

Microsoft.Maps.loadModule('Microsoft.Maps.GeoJson', function () {

	//Create a feature collection.
	var featureCollection = {
		type: 'FeatureCollection',
		features: []
	};
	
	//Loop through shapes 
	for(var i = 0; i < shapes.length; i++){
		//Create a GeoJSON feature from the geometry.
		featureCollection.features.push({
			type: 'Feature',
			
			//Convert the shape to a GeoJSON geometry.
			geometry: Microsoft.Maps.GeoJson.write(shapes[i]),
		
			//Capture the id of the shape.
			id: shapes[i].id,
			
			properties: {}
		});	
	}

	//TODO: Add your logic to get central polygon...
	var centerPolygon = featureCollection.features[0]; //Just grabbing the first one for testing.
			
	//Look up the original shape.
	var centralShape;
	
	for(var i = 0; i < shapes.length; i++){
		if(shapes[i].id === centerPolygon.id){
			centralShape = shapes[i];
			break;
		}
	}
	
	//Do something with the original shape.
	
});