source: branches/HeuristicLab.Problems.GrammaticalOptimization/SharpVectorModel/Paths/SvgPathSegLineto.cs @ 13005

using System;
using System.Text;

namespace SharpVectors.Dom.Svg
{
  public abstract class SvgPathSegLineto : SvgPathSeg
  {
    protected SvgPathSegLineto(SvgPathSegType type) : base(type)
    {
    }

    public abstract override SvgPointF AbsXY{get;}

    private SvgPointF getPrevPoint()
    {
      SvgPathSeg prevSeg = PreviousSeg;
      SvgPointF prevPoint;
      if(prevSeg == null)
      {
        prevPoint = new SvgPointF(0,0);
      }
      else
      {
        prevPoint = prevSeg.AbsXY;
      }
      return prevPoint;
    }

    public override double StartAngle
    {
      get
      {
        SvgPointF prevPoint = getPrevPoint();
        SvgPointF curPoint = AbsXY;

        double dx = curPoint.X - prevPoint.X;
        double dy = curPoint.Y - prevPoint.Y;

        double a = (Math.Atan2(dy, dx) * 180 / Math.PI);
        a += 270;
        a %= 360;
        return a;
      }
    }

    public override double EndAngle
    {
      get
      {
        double a = StartAngle;
        a += 180;
        a %= 360;
        return a;
      }
    }

    public override double Length
    {
      get
      {
        SvgPointF prevPoint = getPrevPoint();
        SvgPointF thisPoint = AbsXY;

        double dx = thisPoint.X - prevPoint.X;
        double dy = thisPoint.Y - prevPoint.Y;

        return Math.Sqrt(dx*dx+dy*dy);
      }
    }
  }
}