Roads API 最多可接受沿路线收集的 100 个 GPS 点,并返回类似的数据集,其中的点会贴合到车辆行驶的最可能道路上。您可以选择请求对点进行插值,从而生成一条平滑贴合道路几何形状的路径。
请求
您必须使用 HTTPS 以以下形式发送贴合到道路的请求:
https://roads.googleapis.com/v1/snapToRoads?parameters&key=YOUR_API_KEY必需参数
-
路径
要贴合的路径。路径参数接受纬度/经度对的列表。纬度和经度值应以英文逗号分隔。坐标应以竖线字符“|”分隔。例如:
path=60.170880,24.942795|60.170879,24.942796|60.170877,24.942796。注意:贴合算法最适合距离不太远的点。如果您发现出现奇怪的贴合行为,请尝试创建点间距更小的路径。为确保道路贴合效果最佳,您应尽量提供连续点对之间距离不超过 300 米的路径。这也有助于处理因 GPS 信号丢失或噪声而导致的连续点之间出现的任何孤立的长跳跃。
可选参数
-
插值
是否对路径进行插值以纳入构成完整道路几何形状的所有点。如果为 true,系统还会返回其他插值点,从而生成一条平滑的路径,该路径可顺畅地沿着道路的几何形状行进,即使在转弯处和隧道中也是如此。插值后的路径很可能包含比原始路径更多的点。默认值为
false。
示例
以下请求会将指定点贴合到道路几何图形。这组特定的数据沿环形道路分布;设置 interpolate=true 可使返回的几何图形与道路的曲率相匹配。使用 interpolate=false 时,贴合的路径仍会沿道路行进,但生成的多段线不够平滑。
网址
https://roads.googleapis.com/v1/snapToRoads ?interpolate=true &path=-35.27801%2C149.12958%7C-35.28032%2C149.12907%7C-35.28099%2C149.12929%7C-35.28144%2C149.12984%7C-35.28194%2C149.13003%7C-35.28282%2C149.12956%7C-35.28302%2C149.12881%7C-35.28473%2C149.12836 &key=YOUR_API_KEY
cURL
curl -L -X GET 'https://roads.googleapis.com/v1/snapToRoads?path=-35.27801%2C149.12958%7C-35.28032%2C149.12907%7C-35.28099%2C149.12929%7C-35.28144%2C149.12984%7C-35.28194%2C149.13003%7C-35.28282%2C149.12956%7C-35.28302%2C149.12881%7C-35.28473%2C149.12836&interpolate=true&key=YOUR_API_KEY'
响应
对于每个有效请求,Roads API 都会以请求网址中指示的格式返回响应,例如以下 JSON 响应。
{ "snappedPoints": [ { "location": { "latitude": -35.27800489993019, "longitude": 149.129531998742 }, "originalIndex": 0, "placeId": "ChIJr_xl0GdNFmsRsUtUbW7qABM", }, { "location": { "latitude": -35.2784195, "longitude": 149.12946589999999 }, "placeId": "ChIJr_xl0GdNFmsRsUtUbW7qABM", }, { "location": { "latitude": -35.2784195, "longitude": 149.12946589999999 }, "placeId": "ChIJ6aXGemhNFmsRZE_zHqhmrG4", }, { "location": { "latitude": -35.2792731, "longitude": 149.12933809999998 }, "placeId": "ChIJ6aXGemhNFmsRZE_zHqhmrG4", }, { "location": { "latitude": -35.2792731, "longitude": 149.12933809999998 }, "placeId": "ChIJTcTdZ2hNFmsRXokM4mWCWfk", }, { "location": { "latitude": -35.279557, "longitude": 149.1292973 }, "placeId": "ChIJTcTdZ2hNFmsRXokM4mWCWfk", }, { "location": { "latitude": -35.279557, "longitude": 149.1292973 }, "placeId": "ChIJiUfNQmhNFmsRSsAI-1m6y1g", }, { "location": { "latitude": -35.279610999999996, "longitude": 149.1292889 }, "placeId": "ChIJiUfNQmhNFmsRSsAI-1m6y1g", }, { "location": { "latitude": -35.2796484, "longitude": 149.1292791 }, "placeId": "ChIJiUfNQmhNFmsRSsAI-1m6y1g", }, { "location": { "latitude": -35.2796484, "longitude": 149.1292791 }, "placeId": "ChIJ_RyFQ2hNFmsRoHJAbW7qABM", }, { "location": { "latitude": -35.279947299999996, "longitude": 149.1291894 }, "placeId": "ChIJ_RyFQ2hNFmsRoHJAbW7qABM", }, { "location": { "latitude": -35.279947299999996, "longitude": 149.1291894 }, "placeId": "ChIJOyypT2hNFmsRZBtscGL0htw", }, { "location": { "latitude": -35.280323564795005, "longitude": 149.1290903128365 }, "originalIndex": 1, "placeId": "ChIJOyypT2hNFmsRZBtscGL0htw", }, { "location": { "latitude": -35.2803426, "longitude": 149.12908529999999 }, "placeId": "ChIJOyypT2hNFmsRZBtscGL0htw", }, { "location": { "latitude": -35.2803426, "longitude": 149.12908529999999 }, "placeId": "ChIJr8xRTGhNFmsRzMb-rxgjspc", }, { "location": { "latitude": -35.280409899999995, "longitude": 149.1290699 }, "placeId": "ChIJr8xRTGhNFmsRzMb-rxgjspc", }, { "location": { "latitude": -35.28048179999999, "longitude": 149.129062 }, "placeId": "ChIJr8xRTGhNFmsRzMb-rxgjspc", }, { "location": { "latitude": -35.2805541, "longitude": 149.1290623 }, "placeId": "ChIJr8xRTGhNFmsRzMb-rxgjspc", }, { "location": { "latitude": -35.280626, "longitude": 149.1290712 }, "placeId": "ChIJr8xRTGhNFmsRzMb-rxgjspc", }, { "location": { "latitude": -35.280626, "longitude": 149.1290712 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.280695099999996, "longitude": 149.12908489999998 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2807629, "longitude": 149.1291046 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2808294, "longitude": 149.1291306 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2809064, "longitude": 149.1291693 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.280968200000004, "longitude": 149.129208 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.28101395754623, "longitude": 149.1292430025548 }, "originalIndex": 2, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.28103840000001, "longitude": 149.1292617 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2810936, "longitude": 149.1293121 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2810979, "longitude": 149.1293176 }, "placeId": "ChIJv5r0smlNFmsR5nunau79Fv4", }, { "location": { "latitude": -35.2810979, "longitude": 149.1293176 }, "placeId": "ChIJpYMSrmlNFmsRXkCoIkZxgBg", }, { "location": { "latitude": -35.281152399999996, "longitude": 149.1294256 }, "placeId": "ChIJpYMSrmlNFmsRXkCoIkZxgBg", }, { "location": { "latitude": -35.281152399999996, "longitude": 149.1294256 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2811784, "longitude": 149.1294706 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2812258, "longitude": 149.1295413 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2812771, "longitude": 149.12960759999999 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281332, "longitude": 149.1296695 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2813904, "longitude": 149.12972670000002 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281451700000005, "longitude": 149.1297788 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.28146506991143, "longitude": 149.12978858234607 }, "originalIndex": 3, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.28151580000001, "longitude": 149.1298257 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.28158259999999, "longitude": 149.129867 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281666099999995, "longitude": 149.1299091 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2817377, "longitude": 149.1299379 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281810899999996, "longitude": 149.1299602 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281884999999996, "longitude": 149.1299765 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.28194399606459, "longitude": 149.1299842294294 }, "originalIndex": 4, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.281959799999996, "longitude": 149.12998629999998 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.282035199999996, "longitude": 149.1299895 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2821254, "longitude": 149.1299851 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.282199999999996, "longitude": 149.1299743 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2822739, "longitude": 149.1299573 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2823468, "longitude": 149.129934 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2824178, "longitude": 149.1299043 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2824379, "longitude": 149.1298945 }, "placeId": "ChIJ601MoWlNFmsR5mvkfPp2ovA", }, { "location": { "latitude": -35.2824379, "longitude": 149.1298945 }, "placeId": "ChIJe9LPnWlNFmsR7mJw8mYHwG0", }, { "location": { "latitude": -35.282472999999996, "longitude": 149.1298835 }, "placeId": "ChIJe9LPnWlNFmsR7mJw8mYHwG0", }, { "location": { "latitude": -35.2825375, "longitude": 149.1298525 }, "placeId": "ChIJe9LPnWlNFmsR7mJw8mYHwG0", }, { "location": { "latitude": -35.28257309999999, "longitude": 149.1298319 }, "placeId": "ChIJe9LPnWlNFmsR7mJw8mYHwG0", }, { "location": { "latitude": -35.28257309999999, "longitude": 149.1298319 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.282665400000006, "longitude": 149.12974459999998 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.28274030000001, "longitude": 149.1296645 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.282809799999995, "longitude": 149.12957799999998 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.28282136229385, "longitude": 149.12956142620385 }, "originalIndex": 5, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.2828744, "longitude": 149.1294854 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.282922299999996, "longitude": 149.1294044 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.282931500000004, "longitude": 149.1293876 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.2830263, "longitude": 149.1291788 }, "placeId": "ChIJaUpThGlNFmsRMHWxoH7EOsc", }, { "location": { "latitude": -35.2830263, "longitude": 149.1291788 }, "placeId": "ChIJyd3JiWlNFmsR9RUq2ySTTZQ", }, { "location": { "latitude": -35.283054, "longitude": 149.1290996 }, "placeId": "ChIJyd3JiWlNFmsR9RUq2ySTTZQ", }, { "location": { "latitude": -35.2830794, "longitude": 149.1290094 }, "placeId": "ChIJyd3JiWlNFmsR9RUq2ySTTZQ", }, { "location": { "latitude": -35.2830794, "longitude": 149.1290094 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.28313383700836, "longitude": 149.12893500604946 }, "originalIndex": 6, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.283134499999996, "longitude": 149.12893409999998 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.283190399999995, "longitude": 149.1288668 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2832503, "longitude": 149.1288041 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2833133, "longitude": 149.1287463 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2833794, "longitude": 149.128694 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.283448299999996, "longitude": 149.128647 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2835199, "longitude": 149.1286054 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2835934, "longitude": 149.1285699 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.283668899999995, "longitude": 149.12854059999998 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.28372649999999, "longitude": 149.1285237 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.28386179999999, "longitude": 149.12849319999998 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2839978, "longitude": 149.1284682 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2840205, "longitude": 149.12846779999998 }, "placeId": "ChIJWSb8ImpNFmsRp_4JAxJFE1A", }, { "location": { "latitude": -35.2840205, "longitude": 149.12846779999998 }, "placeId": "ChIJZe8tFWpNFmsR4brZ1vldk2E", }, { "location": { "latitude": -35.2840524, "longitude": 149.12845969999998 }, "placeId": "ChIJZe8tFWpNFmsR4brZ1vldk2E", }, { "location": { "latitude": -35.284341500000004, "longitude": 149.1284124 }, "placeId": "ChIJZe8tFWpNFmsR4brZ1vldk2E", }, { "location": { "latitude": -35.2843875, "longitude": 149.1284034 }, "placeId": "ChIJZe8tFWpNFmsR4brZ1vldk2E", }, { "location": { "latitude": -35.2843875, "longitude": 149.1284034 }, "placeId": "ChIJVx7Ta2pNFmsRx9OI9CnN5tI", }, { "location": { "latitude": -35.2845916, "longitude": 149.1283726 }, "placeId": "ChIJVx7Ta2pNFmsRx9OI9CnN5tI", }, { "location": { "latitude": -35.2845916, "longitude": 149.1283726 }, "placeId": "ChIJtWxAZmpNFmsRlbUCkc6VtnA", }, { "location": { "latitude": -35.28459730000001, "longitude": 149.1283703 }, "placeId": "ChIJtWxAZmpNFmsRlbUCkc6VtnA", }, { "location": { "latitude": -35.284728747199374, "longitude": 149.12834860726772 }, "originalIndex": 7, "placeId": "ChIJtWxAZmpNFmsRlbUCkc6VtnA", }, ], }
响应使用以下架构。
SnapToRoadsResponse
| 字段 | 必需 | 类型 | 说明 |
|---|---|---|---|
|
可选 | 数组<SnappedPoint> |
贴合点的数组。 如需了解详情,请参阅 SnappedPoint。 |
|
可选 | 字符串 |
包含用户可见警告的字符串。 |
SnappedPoint
| 字段 | 必需 | 类型 | 说明 |
|---|---|---|---|
|
required | LatitudeLongitudeLiteral | 如需了解详情,请参阅 LatitudeLongitudeLiteral。 |
|
required | 字符串 |
地点的唯一标识符。Roads API 返回的所有地点 ID 都对应于路段。 |
|
可选 | 数值 |
一个整数,用于指示原始请求中的相应值。请求中的每个值都应映射到响应中的贴靠值。不过,如果您已将 interpolate 设置为 true,或者您使用的是最近的道路,则响应中包含的坐标数量可能会多于请求中包含的坐标数量。内插值不会有 |
LatitudeLongitudeLiteral
一个对象,用于描述以十进制度为单位的纬度和经度所表示的特定位置。
| 字段 | 必需 | 类型 | 说明 |
|---|---|---|---|
|
required | 数值 |
纬度(以十进制度为单位) |
|
required | 数值 |
经度(以十进制度为单位) |
演示
- 在地图上点击以创建车辆轨迹。请注意,如果点之间的距离过远,可能无法正确贴靠。
- 双击可将轨迹贴合到道路上。
以全屏模式查看此示例。
JavaScript
var apiKey = 'YOUR_API_KEY_HERE'; var map; var drawingManager; var placeIdArray = []; var polylines = []; var snappedCoordinates = []; function initialize() { var mapOptions = { zoom: 17, center: {lat: -33.8667, lng: 151.1955,} }; map = new google.maps.Map(document.getElementById('map'), mapOptions); // Adds a Places search box. Searching for a place will center the map on that // location. map.controls[google.maps.ControlPosition.RIGHT_TOP].push( document.getElementById('bar')); var autocomplete = new google.maps.places.Autocomplete( document.getElementById('autoc')); autocomplete.bindTo('bounds', map); autocomplete.addListener('place_changed', function() { var place = autocomplete.getPlace(); if (place.geometry.viewport) { map.fitBounds(place.geometry.viewport); } else { map.setCenter(place.geometry.location); map.setZoom(17); } }); // Enables the polyline drawing control. Click on the map to start drawing a // polyline. Each click will add a new vertice. Double-click to stop drawing. drawingManager = new google.maps.drawing.DrawingManager({ drawingMode: google.maps.drawing.OverlayType.POLYLINE, drawingControl: true, drawingControlOptions: { position: google.maps.ControlPosition.TOP_CENTER, drawingModes: [ google.maps.drawing.OverlayType.POLYLINE ] }, polylineOptions: { strokeColor: '#696969', strokeWeight: 2, strokeOpacity: 0.3, } }); drawingManager.setMap(map); // Snap-to-road when the polyline is completed. drawingManager.addListener('polylinecomplete', function(poly) { var path = poly.getPath(); polylines.push(poly); placeIdArray = []; runSnapToRoad(path); }); // Clear button. Click to remove all polylines. document.getElementById('clear').addEventListener('click', function(event) { event.preventDefault(); for (var i = 0; i < polylines.length; ++i) { polylines[i].setMap(null); } polylines = []; return false; }); } // Snap a user-created polyline to roads and draw the snapped path function runSnapToRoad(path) { var pathValues = []; for (var i = 0; i < path.getLength(); i++) { pathValues.push(path.getAt(i).toUrlValue()); } $.get('https://roads.googleapis.com/v1/snapToRoads', { interpolate: true, key: apiKey, path: pathValues.join('|') }, function(data) { processSnapToRoadResponse(data); drawSnappedPolyline(); }); } // Store snapped polyline returned by the snap-to-road service. function processSnapToRoadResponse(data) { snappedCoordinates = []; placeIdArray = []; for (var i = 0; i < data.snappedPoints.length; i++) { var latlng = new google.maps.LatLng( data.snappedPoints[i].location.latitude, data.snappedPoints[i].location.longitude); snappedCoordinates.push(latlng); placeIdArray.push(data.snappedPoints[i].placeId); } } // Draws the snapped polyline (after processing snap-to-road response). function drawSnappedPolyline() { var snappedPolyline = new google.maps.Polyline({ path: snappedCoordinates, strokeColor: '#add8e6', strokeWeight: 4, strokeOpacity: 0.9, }); snappedPolyline.setMap(map); polylines.push(snappedPolyline); } $(window).load(initialize);
JavaScript + HTML
<!DOCTYPE html> <html> <head> <meta name="viewport" content="initial-scale=1.0, user-scalable=no"> <meta charset="utf-8"> <title>Roads API Demo</title> <style> html, body, #map { height: 100%; margin: 0px; padding: 0px } #panel { position: absolute; top: 5px; left: 50%; margin-left: -180px; z-index: 5; background-color: #fff; padding: 5px; border: 1px solid #999; } #bar { width: 240px; background-color: rgba(255, 255, 255, 0.75); margin: 8px; padding: 4px; border-radius: 4px; } #autoc { width: 100%; box-sizing: border-box; } </style> <script src="https://www.gstatic.com/external_hosted/jquery2.min.js"></script> <script src="https://maps.googleapis.com/maps/api/js?libraries=drawing,places&key=YOUR_API_KEY"></script> <script> var apiKey = 'YOUR_API_KEY_HERE'; var map; var drawingManager; var placeIdArray = []; var polylines = []; var snappedCoordinates = []; function initialize() { var mapOptions = { zoom: 17, center: {lat: -33.8667, lng: 151.1955,} }; map = new google.maps.Map(document.getElementById('map'), mapOptions); // Adds a Places search box. Searching for a place will center the map on that // location. map.controls[google.maps.ControlPosition.RIGHT_TOP].push( document.getElementById('bar')); var autocomplete = new google.maps.places.Autocomplete( document.getElementById('autoc')); autocomplete.bindTo('bounds', map); autocomplete.addListener('place_changed', function() { var place = autocomplete.getPlace(); if (place.geometry.viewport) { map.fitBounds(place.geometry.viewport); } else { map.setCenter(place.geometry.location); map.setZoom(17); } }); // Enables the polyline drawing control. Click on the map to start drawing a // polyline. Each click will add a new vertice. Double-click to stop drawing. drawingManager = new google.maps.drawing.DrawingManager({ drawingMode: google.maps.drawing.OverlayType.POLYLINE, drawingControl: true, drawingControlOptions: { position: google.maps.ControlPosition.TOP_CENTER, drawingModes: [ google.maps.drawing.OverlayType.POLYLINE ] }, polylineOptions: { strokeColor: '#696969', strokeWeight: 2, strokeOpacity: 0.3, } }); drawingManager.setMap(map); // Snap-to-road when the polyline is completed. drawingManager.addListener('polylinecomplete', function(poly) { var path = poly.getPath(); polylines.push(poly); placeIdArray = []; runSnapToRoad(path); }); // Clear button. Click to remove all polylines. document.getElementById('clear').addEventListener('click', function(event) { event.preventDefault(); for (var i = 0; i < polylines.length; ++i) { polylines[i].setMap(null); } polylines = []; return false; }); } // Snap a user-created polyline to roads and draw the snapped path function runSnapToRoad(path) { var pathValues = []; for (var i = 0; i < path.getLength(); i++) { pathValues.push(path.getAt(i).toUrlValue()); } $.get('https://roads.googleapis.com/v1/snapToRoads', { interpolate: true, key: apiKey, path: pathValues.join('|') }, function(data) { processSnapToRoadResponse(data); drawSnappedPolyline(); }); } // Store snapped polyline returned by the snap-to-road service. function processSnapToRoadResponse(data) { snappedCoordinates = []; placeIdArray = []; for (var i = 0; i < data.snappedPoints.length; i++) { var latlng = new google.maps.LatLng( data.snappedPoints[i].location.latitude, data.snappedPoints[i].location.longitude); snappedCoordinates.push(latlng); placeIdArray.push(data.snappedPoints[i].placeId); } } // Draws the snapped polyline (after processing snap-to-road response). function drawSnappedPolyline() { var snappedPolyline = new google.maps.Polyline({ path: snappedCoordinates, strokeColor: '#add8e6', strokeWeight: 4, strokeOpacity: 0.9, }); snappedPolyline.setMap(map); polylines.push(snappedPolyline); } $(window).load(initialize); </script> </head> <body> <div id="map"></div> <div id="bar"> <p class="auto"><input type="text" id="autoc"/></p> <p><a id="clear" href="#">Click here</a> to clear map.</p> </div> </body> </html>