public double updateArea() {
      if (prev == null || next == null) {
        return area = Double.POSITIVE_INFINITY;
      }
      return area = weightedArea(prev.x, prev.y, x, y, next.x, next.y);
    }
Apply a penalty from {@code k=0} to {@code k=1} to drop more sharp corners from the resulting geometry.
<p>
{@code k=0} is the default to apply no penalty for corner sharpness and just drop based on effective triangle area
at the vertex. {@code k=0.7} is the recommended setting to drop corners based on weighted effective area.
planetiler-core/src/main/java/com/onthegomap/planetiler/geo/VWSimplifier.java