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MapUtil.ToWorldCoordinate get Decimal Degrees

#1

Is there a way to always get Decimal Degrees with MapUtil.ToWorldCoordinate?
When map Units are set to decimal degree SRID 4326 I can get decimal degrees from this function as desired.
But when in mercator projection SRID 3395 in Meter, I always get meter values from this function. But they do not appear to be Northing, Easting Values, so I am not sure how to convert to Degrees.
To make my solution work I either need an option for decimal degrees always from this function or a way to use mercator with Degrees and not meters which does not appear to be a valid choice with Proj.

I tried to use Proj convert string as per: https://proj.org/operations/conversions/unitconvert.html
But it does not seem to be supported with the wrapped version of the library in thinkGeo dependencies.

#2

Thanks Chris,
You can use the projection converter to convert it to 4326.

ProjectionConverter projectionConverter = new ProjectionConverter(3395, 4326);
projectionConverter.Open();
PointShape newCenterPoint = projectionConverter.ConvertToInternalProjection(centerPoint) as PointShape;

Thanks

Frank

#3

I tried the code snippet you sent, but I got the following exception:
“latitude or longitude exceeded limits”
My map is in Meters (Mercator). Here is the rest of my code in this section:
Point currentPoint = e.GetPosition(GlobalObjects.Instance.Map);
PointShape worldPoint = MapUtil.ToWorldCoordinate(GlobalObjects.Instance.Map.CurrentExtent, (float)currentPoint.X, (float)currentPoint.Y, (float)GlobalObjects.Instance.xMap.ActualWidth, (float)GlobalObjects.Instance.Map.ActualHeight);

Here is an example value of my centerPoint that fails conversion.
{-2490404.26965435,-1591905.47432807,0}

#4

Nevermind, I needed to use .ConvertToExternalProjection.
Now it works fine, thanks.

#5

Thanks Chris,
Good to know it works. Let us know if you have any more question.

Thanks

Frank