protected virtual SnapInfo ComputeSnappedLocation(GeoMouseArgs e, Coordinate coordinate)
{
SnapInfo snapInfo = null;
if (coordinate == null)
{
return(snapInfo);
}
snapInfo = ComputeSnappedLocation(e);
if (snapInfo == null)
{
return(snapInfo);
}
coordinate.X = snapInfo.Coordinate.X;
coordinate.Y = snapInfo.Coordinate.Y;
coordinate.Z = snapInfo.Coordinate.Z;
coordinate.M = snapInfo.Coordinate.M;
return(snapInfo);
}
/// <summary>
/// Computes a snapped coordinate. If the mouse is near a snappable object, the output
/// location of the mouse will be the coordinates of the object rather than the actual
/// mouse coords.
/// </summary>
/// <param name="e">The event args.</param>
/// <returns>SnapInfo</returns>
protected virtual SnapInfo ComputeSnappedLocation(GeoMouseArgs e)
{
SnapInfo snapInfo = null;
if (SnapLayers == null || e == null || Map == null || SnapMode == SnapMode.None)
{
return(snapInfo);
}
Rectangle mouseRect = new Rectangle(e.X - SnapTol, e.Y - SnapTol, SnapTol * 2, SnapTol * 2);
Extent extent = Map.PixelToProj(mouseRect);
if (extent == null)
{
return(snapInfo);
}
if (SnapMode == SnapMode.None)
{
return(snapInfo);
}
Tuple <IFeature, Coordinate> tuple = null;
SnapMode snapMode = SnapMode.None;
if ((SnapMode & SnapMode.Point) > 0)
{
foreach (IFeatureLayer layer in SnapLayers.Where(_ => _.Snappable && _.IsVisible))
{
tuple = ComputSnapPointModeFeature(layer, extent);
if (tuple != null)
{
snapMode = SnapMode.Point;
goto Success;
}
}
}
if ((SnapMode & SnapMode.End) > 0)
{
foreach (IFeatureLayer layer in SnapLayers.Where(_ => _.Snappable && _.IsVisible))
{
tuple = ComputSnapEndModeFeature(layer, extent);
if (tuple != null)
{
snapMode = SnapMode.End;
goto Success;
}
}
}
if ((SnapMode & SnapMode.Vertex) > 0)
{
foreach (IFeatureLayer layer in SnapLayers.Where(_ => _.Snappable && _.IsVisible))
{
tuple = ComputSnapVertexModeFeature(layer, extent);
if (tuple != null)
{
snapMode = SnapMode.Vertex;
goto Success;
}
}
}
if ((SnapMode & SnapMode.Edege) > 0)
{
foreach (IFeatureLayer layer in SnapLayers.Where(_ => _.Snappable && _.IsVisible))
{
tuple = ComputSnapEdegeModeFeature(layer, extent, e.GeographicLocation);
if (tuple != null)
{
snapMode = SnapMode.Edege;
goto Success;
}
}
}
Success:
if (tuple != null)
{
snapInfo = new SnapInfo()
{
Feature = tuple.Item1,
Coordinate = tuple.Item2,
SnapMode = snapMode
};
}
return(snapInfo);
}
