code: @Pure
  	public int getPointIndex(int groupIndex, Point2D<?, ?> point2d) {
  		if (!this.containsPoint(point2d, groupIndex)) {
  			return -1;
  		}
  		Point2d cur = null;
  		int pos = -1;
  		for (int i = 0; i < getPointCountInGroup(groupIndex); ++i) {
  			cur = getPointAt(groupIndex, i);
  			if (cur.epsilonEquals(point2d, MapElementConstants.POINT_FUSION_DISTANCE)) {
  				pos = i;
  				break;
  			}
  		}
  
  		return (firstInGroup(groupIndex) + pos * 2) / 2;
  	}
docs: Replies the global index of the point2d in the given group.
  
  @param groupIndex the group index.
  @param point2d  is the point in the group
  @return the global index of the point or <code>-1</code> if not found