Commented Unassigned: ProjToPixel Returning outrageous values [25373]

Hi,

I have a Winforms C# app that loads a number of map layers in stateplane projection. It also has a GPS interface that requires:

-an on-the-fly projection from decimal degrees to the stateplane coordinate system
-display of the GPS position using .ProjToPixel() and .DrawCircleEx().

I am seeing that the call to ProjToPixel is returning screen coordinates that are sometimes negative, but often outside the screen extent of the map control.

Here is my code, perhaps someone can point out what I am doing wrong?

```
MapWinGIS.Shapefile fGPSLocation = new MapWinGIS.Shapefile();
if (!fGPSLocation.CreateNewWithShapeID("", MapWinGIS.ShpfileType.SHP_POINT))
return false;

MapWinGIS.Shape shpGPS = new MapWinGIS.Shape();
shpGPS.ShapeType = MapWinGIS.ShpfileType.SHP_POINT;
double dLat = lat;
double dLng = lng;
double dLatPrj = 0.0;
double dLngPrj = 0.0;

String err = String.Format("GPS: Lat={0}, Lng={1}", dLat, dLng);
Console.WriteLine(err);
try
{
shpGPS.AddPoint(dLng, dLat);
int nShape = -1;
nShape = fGPSLocation.EditAddShape(shpGPS);

MapWinGIS.GeoProjection projStart = new MapWinGIS.GeoProjection();
projStart.ImportFromEPSG(epsgCodeGeographic);
fGPSLocation.GeoProjection = projStart;
MapWinGIS.GeoProjection proj = new MapWinGIS.GeoProjection();
proj.ImportFromEPSG(epsgCodeStateplane);
int nReprojectedCount = 0;
fGPSLocation.ReprojectInPlace(proj, ref nReprojectedCount);
fGPSLocation.get_Shape(0).get_XY(0, ref dLngPrj, ref dLatPrj);
fGPSLocation.StopEditingShapes(true, true, null);

err = String.Format("SP: Y={0}, X={1}", dLatPrj, dLngPrj);
Console.WriteLine(err);

//Now draw the GPS position as a Drawing Layer (screen coordinates)
axMap1.ClearDrawings();
int hDrawing = axMap1.NewDrawing(MapWinGIS.tkDrawReferenceList.dlScreenReferencedList);
//Get the necessary items for the drawing object
double pxX = 0.0;
double pxY = 0.0;
double pxRadius = 0.0;
//Maybe do some math to scale the size of the circle with another CEP (circular error probability) circle
//pxRadius = (Math.Abs(extentCurrent.xMax - extentCurrent.xMin) / 100);
pxRadius = 5;
axMap1.ProjToPixel(dLngPrj, dLatPrj, ref pxX, ref pxY);
err = String.Format("Map: x={0}, y={1}", pxX, pxY);
Console.WriteLine(err);
axMap1.DrawCircleEx(hDrawing, pxX, pxY, pxRadius, Convert.ToUInt32(ColorTranslator.ToOle(Color.Red)), true);
}
```
Comments: ** Comment from web user: sleschinski **

Reviewing this before 4.9.3 beta release:
a) I don't see the point of using Shapefile class for reprojection. It can be done with GeoProjection only (StartTransform, Transform, StopTransform). The same transformation once started can be used for multiple points.
b) as for ProjToPixel giving values outside map extents, I can't tell anything specific, as I don't see what lat, lng values represent / how they were obtained.
I won't close it for now however.