source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/PointMarkers/CenteredTextMarker.cs @ 13792

using System.Threading;
using System.Windows;
using System.Windows.Media;

namespace Microsoft.Research.DynamicDataDisplay.PointMarkers
{
  /// <summary>Renders specified text near the point</summary>
  public class CenteredTextMarker : PointMarker
  {
    public string Text
    {
      get { return (string)GetValue(TextProperty); }
      set { SetValue(TextProperty, value); }
    }

    public static readonly DependencyProperty TextProperty =
      DependencyProperty.Register(
        "Text",
        typeof(string),
        typeof(CenteredTextMarker),
        new FrameworkPropertyMetadata(""));

    public override void Render(DrawingContext dc, Point screenPoint)
    {
      FormattedText textToDraw = new FormattedText(Text, Thread.CurrentThread.CurrentCulture,
         FlowDirection.LeftToRight, new Typeface("Arial"), 12, Brushes.Black);

      double width = textToDraw.Width;
      double height = textToDraw.Height;

      const double verticalShift = -20; // px

      Rect bounds = RectExtensions.FromCenterSize(new Point(screenPoint.X, screenPoint.Y + verticalShift - height / 2),
        new Size(width, height));

      Point loc = bounds.Location;
      bounds = CoordinateUtilities.RectZoom(bounds, 1.05, 1.15);

      dc.DrawLine(new Pen(Brushes.Black, 1), Point.Add(screenPoint, new Vector(0, verticalShift)), screenPoint);
      dc.DrawRectangle(Brushes.White, new Pen(Brushes.Black, 1), bounds);
      dc.DrawText(textToDraw, loc);
    }
  }
}