// Find the midpoint of the line segment that connects the vertices
Vec4 halfwayPoint = firstPoint.add3(secondPoint).divide3(2.0);
Position halfwayPosition = globe.computePositionFromPoint(halfwayPoint);
this._lstMarkerControlPoints.add(new GfrMrkMoveVert(halfwayPosition, halfwayPoint,
this._bmaControlHeight, this._lstMarkerControlPoints.size()));
}