How draw a circle arc into a srcreendisplay

[eddixoncastillo]

What's wrog with this code?.....
IPoint from = arcPoints["from"] as IPoint;
IPoint to = arcPoints["to"] as IPoint;
IPoint thru = arcPoints["thru"] as IPoint;
ICircularArc circularArcThreePoint = new CircularArcClass();
IConstructCircularArc construtionCircularArc = circularArcThreePoint as IConstructCircularArc;
construtionCircularArc.ConstructThreePoints(from, thru, to, true);
IScreenDisplay screenDisplay = m_mapControl.ActiveView.ScreenDisplay;
ESRI.ArcGIS.Display.ISimpleFillSymbol simpleFillSymbol = new ESRI.ArcGIS.Display.SimpleFillSymbolClass();
ESRI.ArcGIS.Display.ISymbol symbol = simpleFillSymbol as ESRI.ArcGIS.Display.ISymbol;
ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberPolygonClass();
screenDisplay.StartDrawing(screenDisplay.hDC, (System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache);
ISegment pSeg;
ISegmentCollection polyline;
pSeg = circularArcThreePoint as ISegment;
polyline = new PolylineClass();
polyline.AddSegment(pSeg);
screenDisplay.DrawPolyline(polyline as IGeometry);
screenDisplay.FinishDrawing();

A try draw an arc circle, and then store in a new feature, but throw the following exception:
COMException was unhandled by user code

[DubravkoAntonic]

You need to specify screenDisplay.SetSymbol before Draw method.
But you didn't specified your symbol line and color.
Here is DrawPolyline snippet from help ISymbol Desktop SDK

IScreenDisplay screenDisplay = activeView.ScreenDisplay;     // Constant   
screenDisplay.StartDrawing(screenDisplay.hDC,
(System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache); // Explicit Cast
ESRI.ArcGIS.Display.IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
rgbColor.Red = 255;    
ESRI.ArcGIS.Display.IColor color = rgbColor; 
// Implicit Cast   
ESRI.ArcGIS.Display.ISimpleLineSymbol simpleLineSymbol = new ESRI.ArcGIS.Display.SimpleLineSymbolClass();   simpleLineSymbol.Color = color;    
ESRI.ArcGIS.Display.ISymbol symbol = (ESRI.ArcGIS.Display.ISymbol)simpleLineSymbol;
// Explicit Cast   
ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberLineClass();
ESRI.ArcGIS.Geometry.IGeometry geometry = rubberBand.TrackNew(screenDisplay, symbol);
screenDisplay.SetSymbol(symbol);
screenDisplay.DrawPolyline(geometry);   
screenDisplay.FinishDrawing(); 

Hope it helps

[eddixoncastillo]

don't work !!!!
Especifically i have to draw circles ( or arc circles)...

here my code:

IScreenDisplay screenDisplay = activeView.ScreenDisplay;
screenDisplay.StartDrawing(screenDisplay.hDC, (System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache);
ESRI.ArcGIS.Display.IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
rgbColor.Red = 255;
ESRI.ArcGIS.Display.IColor color = rgbColor; // Implicit Cast
ESRI.ArcGIS.Display.ISimpleLineSymbol simpleLineSymbol = new ESRI.ArcGIS.Display.SimpleLineSymbolClass();
simpleLineSymbol.Color = color;
ESRI.ArcGIS.Display.ISymbol symbol = (ESRI.ArcGIS.Display.ISymbol)simpleLineSymbol; 
ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberCircleClass();
IGeometry circulo1;
circulo1 = rubberBand.TrackNew(screenDisplay, symbol);
screenDisplay.SetSymbol(symbol);
screenDisplay.DrawPolygon(circulo1);
screenDisplay.FinishDrawing();

[DubravkoAntonic]

Yes it works:), I tried it and it does draw. Put the code in the event OmMouseDown and it will draw rubberband segments on each mouseDown

I wrote this one and it also works in  the same OnMouseDown. Just uncomment DrawPolyline or DrawPolygon and change something to get what you need.

public void DrawSomethingElse(IPoint pPoint)
        {[INDENT]             try
            {[INDENT]                 IPoint a = new PointClass();
                IPoint b = new PointClass();
                a.PutCoords(pPoint.X + 100, pPoint.Y + 100);
                b.PutCoords(pPoint.X - 100, pPoint.Y + 100);

                IScreenDisplay screenDisplay = Extension.ActiveView.ScreenDisplay;     // Constant  
                screenDisplay.StartDrawing(screenDisplay.hDC,
                (System.Int16)ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache); // Explicit Cast
                IRgbColor rgbColor = new ESRI.ArcGIS.Display.RgbColorClass();
                rgbColor.Red = 255;
                IColor color = rgbColor;

                ISimpleLineSymbol simpleLineSymbol = new SimpleLineSymbolClass();
                simpleLineSymbol.Color = color;
                simpleLineSymbol.Width = 3;

                ISimpleMarkerSymbol simpleMarkerSymbol = new SimpleMarkerSymbolClass();
                simpleMarkerSymbol.Color = color;


                ISimpleFillSymbol simpleFillSymbol = new SimpleFillSymbolClass();
                simpleFillSymbol.Color = color;

                ICircularArc circularArcThreePoint = new CircularArcClass();
                IConstructCircularArc construtionCircularArc = circularArcThreePoint as IConstructCircularArc;
                construtionCircularArc.ConstructThreePoints(a, pPoint, b, true);


                object missing = Type.Missing;
                ISymbol symbol = (ESRI.ArcGIS.Display.ISymbol)simpleMarkerSymbol;

                // point
                screenDisplay.SetSymbol(symbol);
                screenDisplay.DrawPoint(a);
                screenDisplay.DrawPoint(b);
                screenDisplay.DrawPoint(pPoint);

                // polygon
                ISegment pSegment = circularArcThreePoint as ISegment;
                ISegmentCollection pSegColl = new PolygonClass();
                pSegColl.AddSegment(pSegment, ref missing, ref missing);
                IGeometry pGeometry = pSegColl as IGeometry;               
                symbol = (ESRI.ArcGIS.Display.ISymbol)simpleFillSymbol;
                screenDisplay.SetSymbol(symbol);
                //screenDisplay.DrawPolygon(pGeometry);

                // poyline
                ISegment pLineSegment = circularArcThreePoint as ISegment;
                ISegmentCollection pLineSegColl = new PolylineClass();
                pLineSegColl.AddSegment(pLineSegment, ref missing, ref missing);
                IGeometry pPolylineGeometry = pLineSegColl as IGeometry;               
                symbol = (ESRI.ArcGIS.Display.ISymbol)simpleLineSymbol;
                screenDisplay.SetSymbol(symbol);
                //screenDisplay.DrawPolyline(pPolylineGeometry);

                screenDisplay.FinishDrawing();
[/INDENT]}
            catch (Exception ex)
            {[INDENT]                 MessageBox.Show(ex.Message);
[/INDENT]}
[/INDENT]}

Hope this will be helpful

regards Dubravko Antoni�?

[eddixoncastillo]

Thank you!!!! It's usefulll