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Drawing pie shapes

#1

Is there any code available that shows how to programatically create pie shapes?



#2

The startAngle and sweepAngle are in degrees.  The angles are clockwise, 0 degrees being North.  Note the angles cannot go beyond 360 and must be positive values. 
  
   private MultipolygonShape BuildPiePolygon(PointShape centerPointShape, double radius, double startAngle, double sweepAngle) 
         { 
             PolygonShape polygonShape = new PolygonShape(); 
             EllipseShape ellipseShape = new EllipseShape(centerPointShape, radius); 
  
             PointShape pointShape1 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
             pointShape1.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle)); 
             polygonShape.OuterRing.Vertices.Add(new Vertex(ellipseShape.Center)); 
             polygonShape.OuterRing.Vertices.Add(new Vertex(pointShape1)); 
  
            if ((sweepAngle > 90)&&(sweepAngle <=180)) 
             { 
                 PointShape midPointShape1 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape1.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 90)); 
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape1)); 
             } 
            else if ((sweepAngle > 180) && (sweepAngle <= 275)) 
             { 
                 PointShape midPointShape1 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape1.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 90)); 
                 PointShape midPointShape2 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape2.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 180)); 
                  
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape1)); 
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape2)); 
                 
             } 
            else if ((sweepAngle > 275) && (sweepAngle <= 360)) 
             { 
                 PointShape midPointShape1 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape1.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 90)); 
                 PointShape midPointShape2 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape2.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 180)); 
                 PointShape midPointShape3 = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
                 midPointShape3.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + 275)); 
  
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape1)); 
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape2)); 
                 polygonShape.OuterRing.Vertices.Add(new Vertex(midPointShape3)); 
             } 
  
             PointShape pointShapeSweep = new PointShape(ellipseShape.Center.X, ellipseShape.Center.Y); 
             pointShapeSweep.TranslateByDegree(ellipseShape.Width, CorrectAngle(startAngle + sweepAngle)); 
             polygonShape.OuterRing.Vertices.Add(new Vertex(pointShapeSweep)); 
             polygonShape.OuterRing.Vertices.Add(new Vertex(ellipseShape.Center)); 
  
             MultipolygonShape intersectionMultiPolygonShape = ellipseShape.GetIntersection(polygonShape); 
             return intersectionMultiPolygonShape; 
             //return polygonShape; 
          } 
  
         private double CorrectAngle(double angle) 
         { 
             double correctAngle; 
             if (angle > 360) 
                 correctAngle = angle - 360; 
             else 
                 correctAngle = angle; 
             return correctAngle; 
  
         }