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

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

#if TEST
using NUnit.Framework;
#endif

namespace SharpVectors.Dom.Svg{
  /// <summary>
  /// The SvgPathSegCurvetoQuadraticSmoothRel interface corresponds to an "relative smooth quadratic curveto" (t) path data command. 
  /// </summary>
  public class SvgPathSegCurvetoQuadraticSmoothRel : SvgPathSegCurvetoQuadratic, ISvgPathSegCurvetoQuadraticSmoothRel
  {
        #region constructors
    internal SvgPathSegCurvetoQuadraticSmoothRel(float x, float y) : base(SvgPathSegType.CurveToQuadraticSmoothRel)
    {
      this.x = x;
      this.y = y;
    }
        #endregion

        #region implementation of SvgpathSegCurvetoQuadraticSmoothRel
    private float x;
    /// <summary>
    /// The absolute X coordinate for the end point of this path segment. 
    /// </summary>
    public float X
    {
      get{return x;}
      set{x = value;}
    }

    private float y;
    /// <summary>
    /// The absolute Y coordinate for the end point of this path segment. 
    /// </summary>
    public float Y
    {
      get{return y;}
      set{y = value;}
    }
        #endregion

        #region public methods
    public override PointF QuadraticX1Y1
    {
      get
      {
        SvgPathSeg prevSeg = PreviousSeg;
        if(prevSeg == null || !(prevSeg is SvgPathSegCurvetoQuadratic))
        {
          return prevSeg.AbsXY;
        }
        else
        {
          PointF prevXY = prevSeg.AbsXY;
          PointF prevX1Y1 = ((SvgPathSegCurvetoQuadratic)prevSeg).QuadraticX1Y1;

          return new PointF(2 * prevXY.X - prevX1Y1.X, 2 * prevXY.Y - prevX1Y1.Y);
        }
      }
    }

    public override PointF AbsXY
    {
      get
      {
        SvgPathSeg prevSeg = PreviousSeg;
        PointF prevPoint;
        if(prevSeg == null) prevPoint = new PointF(0,0);
        else prevPoint = prevSeg.AbsXY;

        return new PointF(prevPoint.X + X, prevPoint.Y + Y);
      }
    }

    public override PointF CubicX1Y1
    {
      get
      {
        PointF prevPoint = PreviousSeg.AbsXY;
        PointF x1y1 = QuadraticX1Y1;

        float x1 = prevPoint.X + (x1y1.X - prevPoint.X) * 2/3;
        float y1 = prevPoint.Y + (x1y1.Y - prevPoint.Y) * 2/3;
      
        return new PointF(x1, y1);
      }
    }

    public override PointF CubicX2Y2
    {
      get
      {
        PointF xy = AbsXY;
        PointF x1y1 = QuadraticX1Y1;
        float x2 = x1y1.X + (xy.X - x1y1.X) / 3;
        float y2 = x1y1.Y + (xy.Y - x1y1.Y) / 3;

        return new PointF(x2, y2);
      }
    }

    public override string PathText
    {
      get
      {
        StringBuilder sb = new StringBuilder();
        sb.Append(PathSegTypeAsLetter);
        sb.Append(X);
        sb.Append(",");
        sb.Append(Y);

        return sb.ToString();
      }
    }
        #endregion

        #region unit tests
        #if TEST
        [TestFixture]
        public class QuadraticSmoothRelTests : QuadraticTests
        {
            public override SvgPathSegList makeSegments()
            {
                return new SvgPathSegList("M-180,10 Q-80,-80 10,10 t190,0", false);
            }

            public override SvgPathSegCurvetoQuadratic getTestSegment()
            {
                return (SvgPathSegCurvetoQuadratic) segments[2];
            }
        }
        #endif
        #endregion
  }
}