private async Task <ArcGIS.Core.Geometry.GeometryEngine.ProximityResult> ComputeDistanceToGeometryAsync(MapPoint clickPoint, FeatureLayer targetLayer, int hitNumber, double searchDistance)
{
FeatureClass featureClass = await targetLayer.GetTableAsync() as FeatureClass;
Geometry searchBuffer = null;
List <Geometry> geometryList = new List <Geometry>();
double closestDistance = double.MaxValue;
ArcGIS.Core.Geometry.GeometryEngine.ProximityResult clickResult = null;
MapPoint closestPoint = null;
bool foundFeatureAndComputedDistance = false;
await QueuingTaskFactory.StartNew(() =>
{
var classDefinition = featureClass.Definition as FeatureClassDefinition;
searchBuffer = GeometryEngine.Project(GeometryEngine.Buffer(clickPoint, searchDistance), classDefinition.SpatialReference);
SpatialQueryFilter spatialFilter = new SpatialQueryFilter()
{
FilterGeometry = searchBuffer,
SpatialRelationship = SpatialRelationship.EnvelopeIntersects
};
RowCursor featureCursor = featureClass.Search(spatialFilter, false);
while (featureCursor.MoveNext())
{
var feature = featureCursor.Current as Feature;
geometryList.Add(feature.Shape);
}
clickPoint = GeometryEngine.Project(clickPoint, classDefinition.SpatialReference) as MapPoint;
foreach (var geometry in geometryList)
{
var geoResult = GeometryEngine.NearestBoundaryPoint(geometry, clickPoint, searchDistance);
if (geoResult.Distance < closestDistance)
{
closestDistance = geoResult.Distance;
clickResult = geoResult;
foundFeatureAndComputedDistance = true;
}
}
});
if (foundFeatureAndComputedDistance)
{
DockPane dockPane = FrameworkApplication.FindDockPane("GeometrySamples_ClosestGeometryPane");
if (dockPane == null)
{
return(new ArcGIS.Core.Geometry.GeometryEngine.ProximityResult());
}
DistancePaneViewModel cgVM = dockPane as DistancePaneViewModel;
cgVM.DistanceDisplayUnit = _linearDisplayUnit;
cgVM.ClickResult = clickResult;
}
return(clickResult);
}