How to Unproject and Reproject Vertices of a Polygon in openlayers with Google maps

Question

I wanting to reproject the vertices of my polygon. I have been able to achieve this for the bounds but having a bit of trouble with the vertices.

           function onFeatureModified(event) {
           var bounds = event.feature.geometry.getBounds();
           var answer = "bottom: " + bounds.bottom + "\n";
           answer += "left: " + bounds.left + "\n";
           answer += "right: " + bounds.right + "\n";
           answer += "top: " + bounds.top + "\n";
           alert(answer);

           var mapProjv =  map.getProjectionObject();
           var epsg4326v = new OpenLayers.Projection("EPSG:4326");
       var verticesNative = event.features[0].geometry.getVertices();
       var verticesLatLon = verticesNative.transform( mapProjv , epsg4326v  );
       var vertices = verticesNative;
           alert(verticesNative);
           }

Below code that works:

           var vertices = event.features[0].geometry.getVertices();
           alert(vertices);

Answer 1

getVertices() method returns an array of OpenLayers.Geometry.Point objects, so you can't call transform() method on it. What you should do instead is to loop through array and call transform() on each object like that:

var vertices = event.features[0].geometry.getVertices();
var transformedVertices = [];
for(var i=0; i < vertices.length; i++){
    transformedVertices.push(vertices[i].transform(
        new OpenLayers.Projection("EPSG:900913"),
        new OpenLayers.Projection("EPSG:4326")
    ));
}

//create new feature with transformed vertices