/// <summary>
/// 绘制相关的文字信息
/// </summary>
/// <param name="dc"></param>
/// <param name="startToLine"></param>
private void SeText(DrawingContext dc, Line2D startToLine)
{
string text = ((int)Math.Round(startToLine.Length)).ToString();
Vector2D middle = startToLine.MiddlePoint;
Vector2D dir = startToLine.Direction;
var rad = dir.AngleFrom(Vector2D.BasisX);
var angle = Extension.RadToDeg(rad);
if (angle > 90 && angle < 270)
{
angle = angle + 180;
}
var md = KernelProperty.MMToPix(middle);
RotateTransform rt = new RotateTransform();
rt.Angle = angle;
rt.CenterX = md.X;
rt.CenterY = md.Y;
dc.PushTransform(rt);
FormattedText ft = new FormattedText(text, new System.Globalization.CultureInfo(0x0804, false), System.Windows.FlowDirection.LeftToRight, new Typeface("微软雅黑"), 14, Brushes.Blue);
dc.DrawText(ft, md);
dc.Pop();
}
/// <summary>
/// 刷新当前图形元素
/// </summary>
public override void Update()
{
DrawingContext dc = this.RenderOpen();
Pen.Freeze(); //冻结画笔，这样能加快绘图速度
this.DashStyle = new System.Windows.Media.DashStyle(new double[] { 5, 5 }, 10);
this.PenColor = Colors.DeepSkyBlue;
this.Pen.EndLineCap = PenLineCap.Triangle;
ArcSegment arc = new ArcSegment();
arc.IsLargeArc = true;
if (start.AngleFrom(end) >= Math.PI)
{
arc.IsLargeArc = false;
}
else
{
arc.IsLargeArc = true;
}
arc.RotationAngle = 0;
arc.Size = new System.Windows.Size(100, 100);
arc.Point = KernelProperty.MMToPix(this.end);
PathGeometry paths = new PathGeometry();
paths.FillRule = FillRule.EvenOdd;
PathFigureCollection pfc = new PathFigureCollection();
PathFigure pf = new PathFigure();
pfc.Add(pf);
pf.StartPoint = KernelProperty.MMToPix(this.start);
pf.Segments.Add(arc);
paths.Figures = pfc;
dc.DrawGeometry(Brush, Pen, paths);
SeText(dc, Line2D.Create(start, end));
dc.Close();
}