2020-05-09

PolyLine Fix and Test

The main issue with PolyLine is that it may contain duplicate points during construction, leading to a series of segment-related geometric calculation problems:

1. Vector calculation: Two duplicate points produce a zero vector.
2. Length calculation: A segment length of 0 easily leads to NaN issues.

Therefore, when constructing a PolyLine, we check the points and throw an exception if any duplicate points are found.

The following issues were identified:

• getEnd in JTS has problems.

• LinearLocation in JTS may have normalization issues.

  val loc1 = new LinearLocation(0, 1, 1.0)
  val loc2 = new LinearLocation(0, 2, 0.0)
  
  loc1 compareTo loc2
  // the output is -1
  

• During interpolation, two points that are too close to each other may be selected.