Samples/Overlays/Topographic/CustomOverlay_TopographicOverlay.html

﻿<!DOCTYPE html>
<html lang="en">
<head>
    <title>Topographic Overlay - Bing Maps Samples</title>

    <meta charset="utf-8" />
	<link rel="shortcut icon" href="/favicon.ico"/>
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no" />
    <meta name="description" content="This sample shows how to create a Topographic Overlay, also commonly known to as an image overlay, using the Custom Overlay class." />
    <meta name="keywords" content="Microsoft maps, map, gis, API, SDK, Bing, Bing Maps" />
    <meta name="author" content="Microsoft Bing Maps" />
    <meta name="screenshot" content="screenshot.jpg" />
    
    <script>
    var map;

    function GetMap()
    {
        map = new Microsoft.Maps.Map('#myMap', {
            center: new Microsoft.Maps.Location(40.25, -123.25),
            zoom: 8
        });

        //Define a custom overlay class that inherts from the CustomOverlay class.
        TopographicOverlay.prototype = new Microsoft.Maps.CustomOverlay();

        //Define a constructor for the custom overlay class.
        function TopographicOverlay(bounds, image) {
            this.bounds = bounds;
            this.image = image;
        }

        //Implement the onAdd method to set up DOM elements, and use setHtmlElement to bind it with the overlay.
        TopographicOverlay.prototype.onAdd = function () {
            //Create an image element that will be used as the overlay.
            img = document.createElement('img');
            img.src = this.image;
            img.style.width = '100%';
            img.style.height = '100%';
            img.style.position = 'absolute';
            this.setHtmlElement(img);
        };

        //Implement the onLoad method to perform custom operations after adding the overlay to the map.
        TopographicOverlay.prototype.onLoad = function () {
            repositionOverlay();

            //Update the position of the image when the view changes.
            Microsoft.Maps.Events.addHandler(map, 'viewchange', function () {
                if (map.getMapTypeId() === Microsoft.Maps.MapTypeId.streetside) {
                    img.style.display = 'none';
                } else {
                    img.style.display = '';
                    repositionOverlay();
                }
            });

            //Update the position of the overlay when the map is resized.
            Microsoft.Maps.Events.addHandler(map, 'mapresize', repositionOverlay);
        };

        function repositionOverlay() {
            //Streach and position the image based on the bounding box pixel coordinates.
            var topLeft = map.tryLocationToPixel(bounds.getNorthwest(), Microsoft.Maps.PixelReference.control);
            var bottomRight = map.tryLocationToPixel(bounds.getSoutheast(), Microsoft.Maps.PixelReference.control);

            img.style.left = topLeft.x + 'px';
            img.style.top = topLeft.y + 'px';
            img.style.width = (bottomRight.x - topLeft.x) + 'px';
            img.style.width = (bottomRight.x - topLeft.x) + 'px';
            img.style.height = (bottomRight.y - topLeft.y) + 'px';
        }

        //The bounding box and url for the image to overlay.
        var bounds = Microsoft.Maps.LocationRect.fromCorners(new Microsoft.Maps.Location(40.5, -123.5), new Microsoft.Maps.Location(40, -123));
        var imageSrc = 'https://bingmapsisdk.blob.core.windows.net/isdksamples/topographicMap.gif';

        //Implement the new custom overlay class. 
        var overlay = new TopographicOverlay(bounds, imageSrc);

        //Add the custom overlay to the map.
        map.layers.insert(overlay);
    }
    </script>
    
</head>
<body>
    <div id="myMap" style="position:relative;width:100%;min-width:290px;height:600px;background-color:gray"></div>

    <fieldset style="width:800px;margin-top:10px;">
        <legend>Custom Overlay - Topographic Overlay Sample</legend>
        This sample shows how to create a Topographic Overlay, also commonly known to as an image overlay, using the Custom Overlay class. 
    </fieldset>

    <script>
        // Dynamic load the Bing Maps Key and Script
        // Get your own Bing Maps key at https://www.microsoft.com/maps
        (async () => {
            let script = document.createElement("script");
            let bingKey = await fetch("https://samples.azuremaps.com/api/GetBingMapsKey").then(r => r.text()).then(key => { return key });
            script.setAttribute("src", `https://www.bing.com/api/maps/mapcontrol?callback=GetMap&key=${bingKey}`);
            document.body.appendChild(script);
        })();
    </script>
</body>
</html>