curve.closestPointT(point [, opt])
t value of the point on the curve that lies closest to
The curve is first subdivided, according to
opt.precision (refer to
curve.length() documentation for more information about precision and curve flattening). Then, one subdivision is identified whose endpoints are the closest to
point. A binary search is then performed on that subdivision, until a curve is found whose diffrence between endpoints' distance to
point lies within
t value of the closest endpoint is returned by the function.
The default value for
opt.precision is 3; this corresponds to maximum observed error of 0.1%.
opt.subdivisions property may be specified, directly providing an array of pre-computed curve subdivisions with which to begin the algorithm. Use the
curve.getSubdivisions() function to obtain an array of curve subdivisions. The
opt.precision property is still necessary, however; it determines the precision of the point search algorithm.