internal override UIElement CreateAnnotation()
{
if (AnnotationElement != null && AnnotationElement.Children.Count == 0)
{
LineCanvas = new Canvas();
if (IsWithCap)
{
shape = new Path();
arrowLine = new ArrowLine();
}
else
{
shape = new Line();
}
shape.Tag = this;
if (ShowLine)
{
if (CanResize)
{
AddThumb();
}
LineCanvas.Children.Add(TextElement);
LineCanvas.Children.Add(shape);
}
SetBindings();
AnnotationElement.Children.Add(LineCanvas);
}
return(AnnotationElement);
}
/// <summary>
/// Calculates the arrow points.
/// </summary>
/// <param name="pathfigure">The Path Figure</param>
/// <param name="point1">The First Point</param>
/// <param name="point2">The Second Point</param>
/// <returns>Returns the <see cref="PathFigure"/> for the arrow.</returns>
private PathFigure CalculateArrow(PathFigure pathfigure, Point point1, Point point2)
{
Matrix matx = new Matrix();
// To made the matx as identity matrix
matx.M11 = 1;
matx.M22 = 1;
// Find the width and height
Point vectPoint = new Point(point1.X - point2.X, point1.Y - point2.Y);
// To find the vector normalization for the width and height , arrow length
vectPoint = ArrowLine.FindNormalization(vectPoint, arrowLength);
PolyLineSegment polyseg = pathfigure.Segments[0] as PolyLineSegment;
polyseg.Points.Clear();
// Rotation matrix calculation and start point calculation of the arrow
var angleRadians = (2 * Math.PI * (arrowAngle / 2)) / 360;
var sine = Math.Sin(angleRadians);
var cosine = Math.Cos(angleRadians);
var matrix = new Matrix(cosine, sine, -sine, cosine, 0, 0);
matx = ArrowLine.MultiplyMatrixes(matx, matrix);
Point tempPoint = ArrowLine.MultiplyMatrixVector(vectPoint, matx);
pathfigure.StartPoint = new Point(point2.X + tempPoint.X, point2.Y + tempPoint.Y);
polyseg.Points.Add(point2);
// Rotation matrix calculation and end point calculation of the arrow
angleRadians = (2 * Math.PI * -arrowAngle) / 360;
sine = Math.Sin(angleRadians);
cosine = Math.Cos(angleRadians);
matrix = new Matrix(cosine, sine, -sine, cosine, 0, 0);
matx = ArrowLine.MultiplyMatrixes(matx, matrix);
tempPoint = ArrowLine.MultiplyMatrixVector(vectPoint, matx);
polyseg.Points.Add(new Point(point2.X + tempPoint.X, point2.Y + tempPoint.Y));
pathfigure.IsClosed = true;
return(pathfigure);
}
