Calculating map scale

DerekVince

Hi all

I have a geometry (an Envelope) defined by 2 lat/lon points.  I'm having trouble wrapping my head around the concept of the camera scale (in 2D) needed to exactly encapsulate that envelope.  I know that if I zoom the current view to the envelope then I will get the scale I'm looking for.  However, this also changes the actual view in the scene.  I'm looking to determine the Scale in a way that does not affect the users view.

MapView view= MapView.Active;
await QueuedTask.Run(() =>
{
   // This works, but changes the user's view. Not good!
   view.ZoomTo(envelope);
   Debug.WriteLine("Scale: " + view.Camera.Scale);
});

Is there a way to manually calculate that scale value, or, to determine it somehow without affecting the view for the user?

Thanks

Amadeus111

It is an old post but maybe it would help someone. You might need to insert the last line in another QueuedTask

 

await QueuedTask.Run(() =>
{
   //1st get the current envelope, so you can go back to it later after calc
   Envelope currentExtent = MapView.Active.Extent;
   currentExtGeometry = currentExtent.Clone();
   
   // Get your scale for the envelope
   view.ZoomTo(envelope);
   Debug.WriteLine("Scale: " + view.Camera.Scale);
   
   //Goback to previous extent
   MapView.Active.ZoomTo(currentExtGeometry);
});