// If the maximum distance from X to the edge AB is greater than "max_dist",
// this method updates "max_dist" and returns true. Otherwise it returns false.
// The case A == B is handled correctly.
public static bool UpdateMaxDistance(S2Point x, S2Point a, S2Point b, ref S1ChordAngle max_dist)
{
var dist = S1ChordAngle.Max(new S1ChordAngle(x, a), new S1ChordAngle(x, b));
if (dist > S1ChordAngle.Right)
{
AlwaysUpdateMinDistance(-x, a, b, ref dist, true);
dist = S1ChordAngle.Straight - dist;
}
if (max_dist < dist)
{
max_dist = dist;
return(true);
}
return(false);
}
private S1ChordAngle EstimateMaxError(R2Point pa, S2Point a, R2Point pb, S2Point b)
{
// See the algorithm description at the top of this file.
// We always tessellate edges longer than 90 degrees on the sphere, since the
// approximation below is not robust enough to handle such edges.
if (a.DotProd(b) < -1e-14)
{
return(S1ChordAngle.Infinity);
}
const double t1 = kInterpolationFraction;
const double t2 = 1 - kInterpolationFraction;
S2Point mid1 = S2.Interpolate(a, b, t1);
S2Point mid2 = S2.Interpolate(a, b, t2);
S2Point pmid1 = proj_.Unproject(Projection.Interpolate(t1, pa, pb));
S2Point pmid2 = proj_.Unproject(Projection.Interpolate(t2, pa, pb));
return(S1ChordAngle.Max(new S1ChordAngle(mid1, pmid1), new S1ChordAngle(mid2, pmid2)));
}