计算RouteBoxer绘制的每个方框的方位

Question

目前我有一个功能齐全的地图，可以在从A到B的路径上使用RouteBoxer，并根据路径（和其他变量）查询融合表，只显示与该路线相关的某些行。我现在遇到的问题是我的地图和查询没有考虑到方向（即它显示了融合表中位于道路两侧的数据）。我知道我需要计算路线中每一步的方位，以便能够确定行进的方向，但我不知道该怎么做。一旦我可以获得方位，使用该值来查询融合表应该很容易。

/// ********************************************************************
    /// ========================= ROUTING FUNCTIONS ========================
    /// ********************************************************************

    // =================================================================
    // Function to Perform routing
    // =================================================================
    function route() {

        document.getElementById("print-directions").style.display = "inline"
        document.getElementById("print-map").style.display = "none"
        // Display loading message. 
        document.getElementById('loading_image').style.visibility="visible";
        printDirectionsFlag = true; 
        // Clear any previous route boxes from the map
        clearBoxes();


        distance = 5;   // Default distance
        var request = {
            origin: document.getElementById("search-input-from").value,
            destination: document.getElementById("search-input-to").value,
            travelMode: google.maps.DirectionsTravelMode.DRIVING
        }

        // Make the directions request
        directionService.route(request, function(result, status) {
            if (status == google.maps.DirectionsStatus.OK) {
                directionsRenderer.setDirections(result);

                // Box around the overview path of the first route
                var path = result.routes[0].overview_path;
                //alert(path);

                var boxes = routeBoxer.box(path, distance);
                drawBoxes(boxes);
            } else {
                alert("Directions query failed: " + status);
            }
        });
    }

    /*

    function calcBearing(){


    }

    */


    // =================================================================
    // Function to conduct a spatial query based on input bounds
    // =================================================================
    function spatialQuery(bounds)
    {
        var str = new String(bounds);
        var coord = str.split(",");  

        clearOverlays(legendItemsArray_LightOnly);
        clearOverlays(legendItemsArray_HeavyOnly);
        clearOverlays(legendItemsArray_LightHeavy);

        // Empty marker arrays
        legendItemsArray_LightOnly = [];
        legendItemsArray_HeavyOnly = [];
        legendItemsArray_LightHeavy = [];

        // Reset and re-run query
        //var fustionTableId = '1SnbgBARsBwxjh5CTUTLSIWd7_yVMxCkX0iXUvf0';
        var querySelect = querySelectRestAreas;
        var queryWhere = "'PUBLISH' = 'Y' AND 'RA_CAT' IN ('RA', 'PA') AND 'RA_TYPE' IN ('B', 'H', 'L')";
        var queryWhereSpatial = " AND ST_INTERSECTS('LATITUDE', RECTANGLE(LATLNG("+coord[0].slice(2)+", "+coord[1].slice(0,coord[1].length-1)+"), LATLNG("+coord[2].slice(2)+", "+coord[3].slice(0,coord[3].length-2)+")))";
        var queryOptions = setQueryOptions();
        var queryWhereClause = queryWhere + queryOptions + queryWhereSpatial;
        var queryOrderBy = "'IIT_NE_ID'";

        loadTable(ftID, querySelect, queryWhereClause, queryOrderBy);
    }

    // =================================================================
    // Function to conduct a spatial query based on input bounds
    // =================================================================
    function updateQuery()
    {
        // Display loading message. 
        document.getElementById('facilities-loader').style.visibility="visible";

        if(printDirectionsFlag){
            route();
        }
        else{

            clearOverlays(legendItemsArray_LightOnly);
            clearOverlays(legendItemsArray_HeavyOnly);
            clearOverlays(legendItemsArray_LightHeavy);

            // Empty marker arrays
            legendItemsArray_LightOnly = [];
            legendItemsArray_HeavyOnly = [];
            legendItemsArray_LightHeavy = [];

            // Reset and re-run query
            //var fustionTableId = '1SnbgBARsBwxjh5CTUTLSIWd7_yVMxCkX0iXUvf0';
            var querySelect = querySelectRestAreas;
            var queryWhere = "'PUBLISH' = 'Y' AND 'RA_CAT' IN ('RA', 'PA') AND 'RA_TYPE' IN ('B', 'H', 'L')";
            //var queryWhereSpatial = " ST_INTERSECTS('LATITUDE', RECTANGLE(LATLNG("+coord[0].slice(2)+", "+coord[1].slice(0,coord[1].length-1)+"), LATLNG("+coord[2].slice(2)+", "+coord[3].slice(0,coord[3].length-2)+")))";

            var  queryOptions = setQueryOptions();

            // alert(queryOptions);
            var queryWhereClause = queryWhere + queryOptions;
            var queryOrderBy = "'IIT_NE_ID'";

            loadTable(ftID, querySelect, queryWhereClause, queryOrderBy);


        }
    }


    // =================================================================
    // Function to draw the array of boxes as polylines on the map
    // =================================================================
    function drawBoxes(boxes) {
        boxpolys = new Array(boxes.length);
        for (var i = 0; i < boxes.length; i++) {
            boxpolys[i] = new google.maps.Rectangle({
                bounds: boxes[i],
                fillOpacity: 0,
                strokeOpacity: 100,
                strokeColor: '#000000',
                strokeWeight: 1,
                map: map
            });
            //alert(boxes[i]);
            //spatialQuery(boxes[i]);
        }

        // Display loading message. 
        document.getElementById('loading_image').style.visibility="hidden";

    }

我不确定轴承计算的位置或实际操作方式。有什么想法吗？