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Lock length when drawing line

#1

 Hi,


  In winformsMap.TrackOverlay when drawing a line,  after set first point I would like


  to lock the line length ( with a length input by user in a textBox)  and at mouseMoved only change the angle, keeping the same


line length for any position from mouse.


 


 Is there some example for this.


 


Thanks. 



#2

Hi Alex,


Here is the sample code:



    public class MyTrackInteractiveOverlay : TrackInteractiveOverlay
    {
        public double lineLength;
        private PointShape point = new PointShape(0, 0);
        private InMemoryFeatureLayer internalFeatureLayer;

        public MyTrackInteractiveOverlay()
            : base()
        {
            internalFeatureLayer = TrackShapeLayer.CloneDeep() as InMemoryFeatureLayer;
        }

        protected override InteractiveResult MouseMoveCore(InteractionArguments interactionArguments)
        {
            point.X = interactionArguments.WorldX;
            point.Y = interactionArguments.WorldY;

            InteractiveResult result = base.MouseMoveCore(interactionArguments);

            if (TrackShapeLayer.InternalFeatures.Count > 0)
            {
                LineShape line = TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1].GetShape() as LineShape;

                double currentLineLength = Math.Sqrt((point.X - line.Vertices[0].X) * (point.X - line.Vertices[0].X) + (point.Y - line.Vertices[0].Y) * (point.Y - line.Vertices[0].Y));
                double newY = (point.Y - line.Vertices[0].Y) * 50 / currentLineLength + line.Vertices[0].Y;
                double newX = (point.X - line.Vertices[0].X) * 50 / currentLineLength + line.Vertices[0].X;

                line.Vertices[1] = new Vertex(newX, newY);
                TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1].WellKnownBinary = line.GetWellKnownBinary();
            }
            return result;
        }

        public override bool IsEmpty
        {
            get
            {
                if (internalFeatureLayer.InternalFeatures.Count == 0 && TrackShapeLayer.InternalFeatures.Count == 0)
                {
                    return true;
                }
                return false;
            }
        }

        protected override InteractiveResult MouseDoubleClickCore(InteractionArguments interactionArguments)
        {
            InteractiveResult result = base.MouseDoubleClickCore(interactionArguments);
            if (TrackShapeLayer.InternalFeatures.Count > 0)
            {
                LineShape line = TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1].GetShape() as LineShape;

                double currentLineLength = Math.Sqrt((point.X - line.Vertices[0].X) * (point.X - line.Vertices[0].X) + (point.Y - line.Vertices[0].Y) * (point.Y - line.Vertices[0].Y));
                double newY = (point.Y - line.Vertices[0].Y) * 50 / currentLineLength + line.Vertices[0].Y;
                double newX = (point.X - line.Vertices[0].X) * 50 / currentLineLength + line.Vertices[0].X;

                line.Vertices[1] = new Vertex(newX, newY);
                TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1].WellKnownBinary = line.GetWellKnownBinary();
            }
            internalFeatureLayer.InternalFeatures.Add(TrackShapeLayer.InternalFeatures[0]);
            TrackShapeLayer.InternalFeatures.Clear();

            return result;
        }

        protected override void DrawCore(GeoCanvas canvas)
        {
            internalFeatureLayer.Open();
            internalFeatureLayer.Draw(canvas, new Collection<SimpleCandidate>());
            base.DrawCore(canvas);
        }
    }


    winformsMap1.TrackOverlay = new MyTrackInteractiveOverlay() { lineLength = 50 };


Hope it helps,


Edgar



#3

 Hi Edgar,


 
Thanks for the sample code.
 
I did a sample with the code (based at DynamicTrackShapes), 
but I could not get the example to work, probably I did some mistake.
 
At your code the lineLength variable is never used, then I  change it to currentLineLength
which is used in MouseMoveCore and MouseDoubleClickCore, is this correct ?
 
I attached my sample project.
 
Thanks in advanced.
 

DynamicTrackShapes_SAMPLE.zip (434 KB)

#4

I’m sorry Alex, I hard-coded the lockLength to 50 forcefully when I’m testing, please roll back to my code and replace the 50 with the field lineLength and everything will be OK. 
  
 Regards, 
 Edgar

#5

 


 Hi Edgar,
 
 Thanks a lot, now it's working.
 
 But it only works with Development Build ( I'm using 6.0.192 ) with Stable/Production Build it's not worked.
 
 
Thanks,
Alexandre

#6

Alex, 



The type of "Feature" in production build is still struct, so you just need to change that two lines of code


TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1].WellKnownBinary = line.GetWellKnownBinary();

to


TrackShapeLayer.InternalFeatures[TrackShapeLayer.InternalFeatures.Count - 1] = new Feature(line.GetWellKnownBinary());

and it will work. 



Regards, 

Edgar



#7

 


 Thanks Edgar,


 


  Now also works in the production version.  


 


 



#8

Glad to hear it works, please let us know if you have any questions. 
  
 Regards, 
 Edgar