Question

有没有办法获得CesiumJS中给定位置的地面高度？我试过了scene.globe.getHeight func，但它返回undefined。

    //marker is a point on map.
var marker = {latitude: 61.08658108795938, longitude: -99.64592791446208};
var height = scene.globe.getHeight( new Cesium.Cartographic(marker.longitude, marker.latitude ) );//undefined

谢谢。

Answer 1

您应该使用sampleTerrain。这是一个例子：

// Construct the default list of terrain sources.
var terrainModels = Cesium.createDefaultTerrainProviderViewModels();

// Construct the viewer, with a high-res terrain source pre-selected.
var viewer = new Cesium.Viewer('cesiumContainer', {
    terrainProviderViewModels: terrainModels,
    selectedTerrainProviderViewModel: terrainModels[1]  // Select STK High-res terrain
});

// Get a reference to the ellipsoid, with terrain on it.  (This API may change soon)
var ellipsoid = viewer.scene.globe.ellipsoid;

// Specify our point of interest.
var pointOfInterest = Cesium.Cartographic.fromDegrees(
    -99.64592791446208, 61.08658108795938, 5000, new Cesium.Cartographic());

// [OPTIONAL] Fly the camera there, to see if we got the right point.
viewer.camera.flyTo({
    destination: ellipsoid.cartographicToCartesian(pointOfInterest,
        new Cesium.Cartesian3())
});

// Sample the terrain (async) and write the answer to the console.
Cesium.sampleTerrain(viewer.terrainProvider, 9, [ pointOfInterest ])
.then(function(samples) {
    console.log('Height in meters is: ' + samples[0].height);
});

Answer 2

这是替代方案：

var marker= new Cesium.Cartesian3.fromDegrees(lon,lat, 0);
markers.push(marker);
var cartographicPositions = Cesium.Ellipsoid.WGS84.cartesianArrayToCartographicArray(markers);
            var HeightCheck=setInterval(function(){
                    if (cesiumTerrainProviderHeightmaps.ready)
                    {
                        clearInterval(HeightCheck);

                        var promise = Cesium.sampleTerrain(cesiumTerrainProviderHeightmaps, 11, cartographicPositions);
                        Cesium.when(promise, function(cartographicPositions) {
                               // you got the altitudes

                            });
                    } else {
                        // "Waiting for height data of terrain...."
                    }
                },1000);

获得地面高度CesiumJS

2 个答案: