Snapping in the Editing functionality

Question

Hi,

While editing features in the Web map viewer, is it possible to snap to edges, vertices and nodes of the edited layer? Also, extrude and reduce the polygon by a specified value? This is an absolute must-have for the client, so any help will be much appreciated.

Thanks
Jolly

JenniferNery · Answer

You can also update graphic Geometry in code-behind without using the Editor.
For example:
private void GraphicsLayer_MouseLeftButtonDown(object sender, GraphicMouseButtonEventArgs e)
{
 Polyline polyline = e.Graphic.Geometry as Polyline;
 Envelope current = polyline.Extent;
 Envelope expand = current.Expand(10);
 Polyline scaled = new Polyline();
 double sx = current.Width > 0 ? expand.Width / current.Width : 1d;
 double sy = current.Height > 0 ? expand.Height / current.Height : 1d;
 foreach (var path in polyline.Paths)
 {
  PointCollection pts = new PointCollection();
  foreach (var p in path)
   pts.Add(new MapPoint((p.X - current.XMin) * sx + expand.XMin, (p.Y - current.YMin) * sy + expand.YMin));
  scaled.Paths.Add(pts);
 }
 e.Graphic.Geometry = scaled;
}

JollyJacob · Answer

Thanks for your reply Jennifer. In the Municipality for which we are doing this project, they sometimes need to extend / contract plot geometry and they want to be able to do so using a user-defined value rather than an arbitary click-and-drag of the mouse extension. If we can't do that using the SL API that pretty much rules out SL and we might have to try this in Javascript instead.

JenniferNery · Answer

Oh you mean scale the geometry? Scale and Rotate is new to v2.2. You can join our beta community to test it out and see if this is something you can use for your application.

However, the Editor.EditVertices with ScaleEnabled=True, does not include a programmatic way of doing something like "ScaleX by some x amount and ScaleY by some y amount" as you suggested.