internal CalculatedArcValues GetCalculatedArcValues()
{
CalculatedArcValues calcVal = new CalculatedArcValues();
/*
* This algorithm is taken from the Batik source. All cudos to the Batik crew.
*/
PointF startPoint = PreviousSeg.AbsXY;
PointF endPoint = AbsXY;
float x0 = startPoint.X;
float y0 = startPoint.Y;
float x = endPoint.X;
float y = endPoint.Y;
// Compute the half distance between the current and the final point
double dx2 = (x0 - x) / 2.0;
double dy2 = (y0 - y) / 2.0;
// Convert angle from degrees to radians
double radAngle = Angle * Math.PI / 180;
double cosAngle = Math.Cos(radAngle);
double sinAngle = Math.Sin(radAngle);
//
// Step 1 : Compute (x1, y1)
//
double x1 = (cosAngle * dx2 + sinAngle * dy2);
double y1 = (-sinAngle * dx2 + cosAngle * dy2);
// Ensure radii are large enough
double rx = Math.Abs(R1);
double ry = Math.Abs(R2);
double Prx = rx * rx;
double Pry = ry * ry;
double Px1 = x1 * x1;
double Py1 = y1 * y1;
// check that radii are large enough
double radiiCheck = Px1/Prx + Py1/Pry;
if (radiiCheck > 1)
{
rx = Math.Sqrt(radiiCheck) * rx;
ry = Math.Sqrt(radiiCheck) * ry;
Prx = rx * rx;
Pry = ry * ry;
}
//
// Step 2 : Compute (cx1, cy1)
//
double sign = (LargeArcFlag == SweepFlag) ? -1 : 1;
double sq = ((Prx*Pry)-(Prx*Py1)-(Pry*Px1)) / ((Prx*Py1)+(Pry*Px1));
sq = (sq < 0) ? 0 : sq;
double coef = (sign * Math.Sqrt(sq));
double cx1 = coef * ((rx * y1) / ry);
double cy1 = coef * -((ry * x1) / rx);
//
// Step 3 : Compute (cx, cy) from (cx1, cy1)
//
double sx2 = (x0 + x) / 2.0;
double sy2 = (y0 + y) / 2.0;
double cx = sx2 + (cosAngle * cx1 - sinAngle * cy1);
double cy = sy2 + (sinAngle * cx1 + cosAngle * cy1);
//
// Step 4 : Compute the angleStart (angle1) and the angleExtent (dangle)
//
double ux = (x1 - cx1); // rx;
double uy = (y1 - cy1); // ry;
double vx = (-x1 - cx1); // rx;
double vy = (-y1 - cy1); // ry;
double p, n;
// Compute the angle start
n = Math.Sqrt((ux * ux) + (uy * uy));
p = ux; // (1 * ux) + (0 * uy)
sign = (uy < 0) ? -1d : 1d;
double angleStart = sign * Math.Acos(p / n);
angleStart = angleStart * 180 / Math.PI;
// Compute the angle extent
n = Math.Sqrt((ux * ux + uy * uy) * (vx * vx + vy * vy));
p = ux * vx + uy * vy;
sign = (ux * vy - uy * vx < 0) ? -1d : 1d;
double angleExtent = sign * Math.Acos(p / n);
angleExtent = angleExtent * 180 / Math.PI;
if(!sweepFlag && angleExtent > 0)
{
angleExtent -= 360f;
}
else if (sweepFlag && angleExtent < 0)
{
angleExtent += 360f;
}
angleExtent %= 360f;
angleStart %= 360f;
calcVal.CorrRx = (float)rx;
calcVal.CorrRy = (float)ry;
calcVal.Cx = (float)cx;
calcVal.Cy = (float)cy;
calcVal.AngleStart = (float)angleStart;
calcVal.AngleExtent = (float)angleExtent;
return calcVal;
}
internal CalculatedArcValues GetCalculatedArcValues()
{
CalculatedArcValues calcVal = new CalculatedArcValues();
/*
* This algorithm is taken from the Batik source. All cudos to the Batik crew.
*/
PointF startPoint = PreviousSeg.AbsXY;
PointF endPoint = AbsXY;
float x0 = startPoint.X;
float y0 = startPoint.Y;
float x = endPoint.X;
float y = endPoint.Y;
// Compute the half distance between the current and the final point
double dx2 = (x0 - x) / 2.0;
double dy2 = (y0 - y) / 2.0;
// Convert angle from degrees to radians
double radAngle = Angle * Math.PI / 180;
double cosAngle = Math.Cos(radAngle);
double sinAngle = Math.Sin(radAngle);
//
// Step 1 : Compute (x1, y1)
//
double x1 = (cosAngle * dx2 + sinAngle * dy2);
double y1 = (-sinAngle * dx2 + cosAngle * dy2);
// Ensure radii are large enough
double rx = Math.Abs(R1);
double ry = Math.Abs(R2);
double Prx = rx * rx;
double Pry = ry * ry;
double Px1 = x1 * x1;
double Py1 = y1 * y1;
// check that radii are large enough
double radiiCheck = Px1 / Prx + Py1 / Pry;
if (radiiCheck > 1)
{
rx = Math.Sqrt(radiiCheck) * rx;
ry = Math.Sqrt(radiiCheck) * ry;
Prx = rx * rx;
Pry = ry * ry;
}
//
// Step 2 : Compute (cx1, cy1)
//
double sign = (LargeArcFlag == SweepFlag) ? -1 : 1;
double sq = ((Prx * Pry) - (Prx * Py1) - (Pry * Px1)) / ((Prx * Py1) + (Pry * Px1));
sq = (sq < 0) ? 0 : sq;
double coef = (sign * Math.Sqrt(sq));
double cx1 = coef * ((rx * y1) / ry);
double cy1 = coef * -((ry * x1) / rx);
//
// Step 3 : Compute (cx, cy) from (cx1, cy1)
//
double sx2 = (x0 + x) / 2.0;
double sy2 = (y0 + y) / 2.0;
double cx = sx2 + (cosAngle * cx1 - sinAngle * cy1);
double cy = sy2 + (sinAngle * cx1 + cosAngle * cy1);
//
// Step 4 : Compute the angleStart (angle1) and the angleExtent (dangle)
//
double ux = (x1 - cx1); // rx;
double uy = (y1 - cy1); // ry;
double vx = (-x1 - cx1); // rx;
double vy = (-y1 - cy1); // ry;
double p, n;
// Compute the angle start
n = Math.Sqrt((ux * ux) + (uy * uy));
p = ux; // (1 * ux) + (0 * uy)
sign = (uy < 0) ? -1d : 1d;
double angleStart = sign * Math.Acos(p / n);
angleStart = angleStart * 180 / Math.PI;
// Compute the angle extent
n = Math.Sqrt((ux * ux + uy * uy) * (vx * vx + vy * vy));
p = ux * vx + uy * vy;
sign = (ux * vy - uy * vx < 0) ? -1d : 1d;
double angleExtent = sign * Math.Acos(p / n);
angleExtent = angleExtent * 180 / Math.PI;
if (!sweepFlag && angleExtent > 0)
{
angleExtent -= 360f;
}
else if (sweepFlag && angleExtent < 0)
{
angleExtent += 360f;
}
angleExtent %= 360f;
angleStart %= 360f;
calcVal.CorrRx = (float)rx;
calcVal.CorrRy = (float)ry;
calcVal.Cx = (float)cx;
calcVal.Cy = (float)cy;
calcVal.AngleStart = (float)angleStart;
calcVal.AngleExtent = (float)angleExtent;
return(calcVal);
}
public GraphicsPath GetGraphicsPath()
{
if (gp == null)
{
gp = new GraphicsPath();
PointF initPoint = new PointF(0, 0);
PointF lastPoint = new PointF(0, 0);
SvgPathSegList segments = (SvgPathSegList)PathSegList;
SvgPathSeg segment;
int nElems = segments.NumberOfItems;
for (int i = 0; i < nElems; i++)
{
segment = (SvgPathSeg)segments.GetItem(i);
if (segment is SvgPathSegMoveto)
{
SvgPathSegMoveto seg = (SvgPathSegMoveto)segment;
gp.StartFigure();
lastPoint = initPoint = seg.AbsXY;
}
else if (segment is SvgPathSegLineto)
{
SvgPathSegLineto seg = (SvgPathSegLineto)segment;
PointF p = seg.AbsXY;
gp.AddLine(lastPoint.X, lastPoint.Y, p.X, p.Y);
lastPoint = p;
}
else if (segment is SvgPathSegCurveto)
{
SvgPathSegCurveto seg = (SvgPathSegCurveto)segment;
PointF xy = seg.AbsXY;
PointF x1y1 = seg.CubicX1Y1;
PointF x2y2 = seg.CubicX2Y2;
gp.AddBezier(lastPoint.X, lastPoint.Y, x1y1.X, x1y1.Y, x2y2.X, x2y2.Y, xy.X, xy.Y);
lastPoint = xy;
}
else if (segment is SvgPathSegArc)
{
SvgPathSegArc seg = (SvgPathSegArc)segment;
PointF p = seg.AbsXY;
if (lastPoint.Equals(p))
{
// If the endpoints (x, y) and (x0, y0) are identical, then this
// is equivalent to omitting the elliptical arc segment entirely.
}
else if (seg.R1 == 0 || seg.R2 == 0)
{
// Ensure radii are valid
gp.AddLine(lastPoint, p);
}
else
{
CalculatedArcValues calcValues = seg.GetCalculatedArcValues();
GraphicsPath gp2 = new GraphicsPath();
gp2.StartFigure();
gp2.AddArc(
calcValues.Cx - calcValues.CorrRx,
calcValues.Cy - calcValues.CorrRy,
calcValues.CorrRx * 2,
calcValues.CorrRy * 2,
calcValues.AngleStart,
calcValues.AngleExtent
);
Matrix matrix = new Matrix();
matrix.Translate(
-calcValues.Cx,
-calcValues.Cy
);
gp2.Transform(matrix);
matrix = new Matrix();
matrix.Rotate(seg.Angle);
gp2.Transform(matrix);
matrix = new Matrix();
matrix.Translate(calcValues.Cx, calcValues.Cy);
gp2.Transform(matrix);
gp.AddPath(gp2, true);
}
lastPoint = p;
}
else if (segment is SvgPathSegClosePath)
{
gp.CloseFigure();
lastPoint = initPoint;
}
}
string fillRule = GetPropertyValue("fill-rule");
if (fillRule == "evenodd")
{
gp.FillMode = FillMode.Alternate;
}
else
{
gp.FillMode = FillMode.Winding;
}
}
return(gp);
}
