SvgPathSegLineto.cs :  » GUI » SharpVectorGraphics » SharpVectors » Dom » Svg » C# / CSharp Open Source

using System;
using System.Drawing;
using System.Text;

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

    public abstract override PointF AbsXY{get;}

    private PointF getPrevPoint()
    {
      SvgPathSeg prevSeg = PreviousSeg;
      PointF prevPoint;
      if(prevSeg == null)
      {
        prevPoint = new PointF(0,0);
      }
      else
      {
        prevPoint = prevSeg.AbsXY;
      }
      return prevPoint;
    }
    public override float StartAngle
    {
      get
      {
        PointF prevPoint = getPrevPoint();
        PointF curPoint = AbsXY;

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

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

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

    public override float Length
    {
      get
      {
        PointF prevPoint = getPrevPoint();
        PointF thisPoint = AbsXY;

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

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