private Polygon CreateThreePointPolygon(List<PointF> pointList)
{
PolyPoint p0 = new PolyPoint(pointList[0]);
PolyPoint p1 = new PolyPoint(pointList[1]);
PolyPoint p2 = new PolyPoint(pointList[2]);
double zeroToOne = GetSlope(pointList[0], pointList[1]);
double zeroToTwo = GetSlope(pointList[0], pointList[2]);
// The slope of oneToOne is more negative
// than oneToTwo. Thus, to maintain clockwise
// order, pointList[1] is the PolyPoint.next
// of pointList[0].
if (zeroToOne < zeroToTwo)
{
p0.next = p1;
p0.prev = p2;
p1.next = p2;
p1.prev = p0;
p2.next = p0;
p2.prev = p1;
}
else
{
p0.next = p2;
p0.prev = p1;
p1.next = p0;
p1.prev = p2;
p2.next = p1;
p2.prev = p0;
}
return new Polygon(p0, p2);
}
private Polygon CreateTwoPointPolygon(List<PointF> pointList)
{
PolyPoint p1 = new PolyPoint(pointList[0]);
PolyPoint p2 = new PolyPoint(pointList[1]);
p1.next = p2;
p1.prev = p2;
p2.next = p1;
p2.prev = p1;
return new Polygon(p1, p2);
}