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

using System;
using System.Drawing;
using SharpVectors.Polynomials;

namespace SharpVectors.Dom.Svg{
  public abstract class SvgPathSegCurveto : SvgPathSeg
  {
        #region constructors
    protected SvgPathSegCurveto(SvgPathSegType type) : base(type)
    {
    }
        #endregion

        #region abstract properties
    public abstract override PointF AbsXY{get;}
    public abstract PointF CubicX1Y1{get;}
    public abstract PointF CubicX2Y2{get;}
        #endregion

        #region public properties
        public override float Length
        {
            get
            {
                return (float) this.getArcLengthPolynomial().Simpson(0, 1);
            }
        }

    public override float StartAngle
    {
      get
      {
        PointF p1 = PreviousSeg.AbsXY;
        PointF p2 = CubicX1Y1;

        float dx = p2.X - p1.X;
        float dy = p2.Y - p1.Y;
        float a = (float)(Math.Atan2(dy, dx) * 180 / Math.PI);
        a += 270;
        a %= 360;
        return a;
      }
    }

    public override float EndAngle
    {
      get
      {
        PointF p1 = CubicX2Y2;
        PointF p2 = AbsXY;

        float dx = p1.X - p2.X;
        float dy = p1.Y - p2.Y;
        float a = (float)(Math.Atan2(dy, dx) * 180 / Math.PI);
        a += 270;
        a %= 360;
        return a;
      }
    }
        #endregion
      
        protected abstract SqrtPolynomial getArcLengthPolynomial();
  }
}