Method ContainsPoint

s2/loop.go:601–629

ContainsPoint returns true if the loop contains the point.

(p Point)

// ContainsPoint returns true if the loop contains the point.
func (l *Loop) ContainsPoint(p Point) bool {
	if !l.index.IsFresh() && !l.bound.ContainsPoint(p) {
		return false
	}

	// For small loops it is faster to just check all the crossings.  We also
	// use this method during loop initialization because InitOriginAndBound()
	// calls Contains() before InitIndex().  Otherwise, we keep track of the
	// number of calls to Contains() and only build the index when enough calls
	// have been made so that we think it is worth the effort.  Note that the
	// code below is structured so that if many calls are made in parallel only
	// one thread builds the index, while the rest continue using brute force
	// until the index is actually available.

	const maxBruteForceVertices = 32
	// TODO(roberts): add unindexed contains calls tracking

	if len(l.index.shapes) == 0 || // Index has not been initialized yet.
		len(l.vertices) <= maxBruteForceVertices {
		return l.bruteForceContainsPoint(p)
	}

	// Otherwise, look up the point in the index.
	it := l.index.Iterator()
	if !it.LocatePoint(p) {
		return false
	}
	return l.iteratorContainsPoint(it, p)
}

// ContainsCell reports whether the given Cell is contained by this Loop.
func (l *Loop) ContainsCell(target Cell) bool {