| public static CounterClockwise ( System.Point pa, System.Point pb, System.Point pc ) : double | ||
| pa | System.Point | Point a. |
| pb | System.Point | Point b. |
| pc | System.Point | Point c. |
| return | double | |
public static double CounterClockwise(Point pa, Point pb, Point pc)
{
double detleft, detright, det;
double detsum, errbound;
Statistic.CounterClockwiseCount++;
detleft = (pa.x - pc.x) * (pb.y - pc.y);
detright = (pa.y - pc.y) * (pb.x - pc.x);
det = detleft - detright;
if (Behavior.NoExact)
{
return det;
}
if (detleft > 0.0)
{
if (detright <= 0.0)
{
return det;
}
else
{
detsum = detleft + detright;
}
}
else if (detleft < 0.0)
{
if (detright >= 0.0)
{
return det;
}
else
{
detsum = -detleft - detright;
}
}
else
{
return det;
}
errbound = ccwerrboundA * detsum;
if ((det >= errbound) || (-det >= errbound))
{
return det;
}
return (double)CounterClockwiseDecimal(pa, pb, pc);
}
public static Point FindCircumcenter(Point torg, Point tdest, Point tapex, ref double xi, ref double eta)
{
double num;
Statistic.CircumcenterCount = Statistic.CircumcenterCount + (long)1;
double num1 = tdest.x - torg.x;
double num2 = tdest.y - torg.y;
double num3 = tapex.x - torg.x;
double num4 = tapex.y - torg.y;
double num5 = num1 * num1 + num2 * num2;
double num6 = num3 * num3 + num4 * num4;
if (!Behavior.NoExact)
{
num = 0.5 / Primitives.CounterClockwise(tdest, tapex, torg);
Statistic.CounterClockwiseCount = Statistic.CounterClockwiseCount - (long)1;
}
else
{
num = 0.5 / (num1 * num4 - num3 * num2);
}
double num7 = (num4 * num5 - num2 * num6) * num;
double num8 = (num1 * num6 - num3 * num5) * num;
xi = (num4 * num7 - num3 * num8) * (2 * num);
eta = (num1 * num8 - num2 * num7) * (2 * num);
return(new Point(torg.x + num7, torg.y + num8));
}