code: VertexIterator queryVertexIterator(boolean b_skip_multi_points) {
  		int geometry = -1;
  		int path = -1;
  		int vertex = -1;
  		int first_vertex = -1;
  		int index = 0;
  		boolean bFound = false;
  
  		for (geometry = getFirstGeometry(); geometry != -1; geometry = getNextGeometry(geometry)) {
  			if (b_skip_multi_points
  					&& !Geometry.isMultiPath(getGeometryType(geometry)))
  				continue;
  
  			for (path = getFirstPath(geometry); path != -1; path = getNextPath(path)) {
  				vertex = getFirstVertex(path);
  				first_vertex = vertex;
  				index = 0;
  				if (vertex == -1)
  					continue;
  
  				bFound = true;
  				break;
  			}
  
  			if (bFound)
  				break;
  		}
  
  		return VertexIterator.create_(this, geometry, path, vertex,
  				first_vertex, index, b_skip_multi_points);
  	}
docs: vertices