int GetWindingNumber(ControlPoint p, Glyph glyphData)
{
ControlPoint p2 = new ControlPoint(p.X + 1000, p.Y);
int result = 0;
foreach (var contour in glyphData.Contours)
{
for (int a = contour.Count - 1, b = 0; b < contour.Count; a = b, b++)
{
ControlPoint pa = contour[a];
ControlPoint pb = contour[b];
if (pa.Y > p.Y && pb.Y < p.Y)
{
if (pa.X > p.X && pb.X > p.X)
{
result++;
}
else if ((pa.X > p.X && pb.X < p.X) || (pa.X < p.X && pb.X > p.X))
{
ControlPoint r = p2 - p;
ControlPoint s = pb - pa;
double t = ControlPoint.VectorProduct((pa - p), s) / ControlPoint.VectorProduct(r, s);
double u = ControlPoint.VectorProduct((p - pa), r) / ControlPoint.VectorProduct(s, r);
if (t >= 0 && u >= 0 && u <= 1)
{
result++;
}
}
}
else if (pa.Y < p.Y && pb.Y > p.Y)
{
if (pa.X > p.X && pb.X > p.X)
{
result--;
}
else if ((pa.X > p.X && pb.X < p.X) || (pa.X < p.X && pb.X > p.X))
{
ControlPoint r = p2 - p;
ControlPoint s = pb - pa;
double t = ControlPoint.VectorProduct((pa - p), s) / ControlPoint.VectorProduct(r, s);
double u = ControlPoint.VectorProduct((p - pa), r) / ControlPoint.VectorProduct(s, r);
if (t >= 0 && u >= 0 && u <= 1)
{
result--;
}
}
}
}
}
return(result);
}
void SearchTree(InputGeometry inputGeometry, ref int pointIndex, PolyNode node)
{
foreach (PolyNode childNode in node.Childs)
{
int startIndex = pointIndex;
foreach (ControlPoint point in childNode.Contour)
{
inputGeometry.AddPoint(point.X, point.Y);
if (pointIndex > startIndex)
{
inputGeometry.AddSegment(pointIndex - 1, pointIndex);
}
pointIndex++;
}
inputGeometry.AddSegment(pointIndex - 1, startIndex);
if (childNode.IsHole)
{
for (int i = 0, j = childNode.Contour.Count - 1, k = childNode.Contour.Count - 2; i < childNode.Contour.Count; k = j, j = i, i++)
{
ControlPoint a1 = childNode.Contour[k];
ControlPoint a2 = childNode.Contour[j];
ControlPoint a3 = childNode.Contour[i];
if (ControlPoint.VectorProduct(a2 - a1, a3 - a1) < 0)
{
ControlPoint c = ((a1 + a3) / 2) - a2;
double x = 2;
ControlPoint hole;
do
{
x /= 2;
hole = a2 + (c * x);
} while (!IsInside(childNode, hole));
inputGeometry.AddHole(hole.X, hole.Y);
break;
}
}
}
SearchTree(inputGeometry, ref pointIndex, childNode);
}
}
