igc

const worldTerrain = Cesium.createWorldTerrain({ requestWaterMask: true, requestVertexNormals: true, }); const viewer = new Cesium.Viewer(“cesiumContainer”, { terrainProvider: worldTerrain, }); // set lighting to true viewer.scene.globe.enableLighting = true; // setup alternative terrain providers const ellipsoidProvider = new Cesium.EllipsoidTerrainProvider(); const vrTheWorldProvider = new Cesium.VRTheWorldTerrainProvider({ url: “http://www.vr-theworld.com/vr-theworld/tiles1.0.0/73/”, credit: “Terrain data courtesy VT MÄK”, }); const arcGisProvider = new Cesium.ArcGISTiledElevationTerrainProvider({ url: “https://elevation3d.arcgis.com/arcgis/rest/services/WorldElevation3D/Terrain3D/ImageServer”, }); // Sine wave const customHeightmapWidth = 32; const customHeightmapHeight = 32; const customHeightmapProvider = new Cesium.CustomHeightmapTerrainProvider( { width: customHeightmapWidth, height: customHeightmapHeight, callback: function (x, y, level) { const width = customHeightmapWidth; const height = customHeightmapHeight; const buffer = new Float32Array(width * height); for (let yy = 0; yy < height; yy++) { for (let xx = 0; xx < width; xx++) { const u = (x + xx / (width – 1)) / Math.pow(2, level); const v = (y + yy / (height – 1)) / Math.pow(2, level); const heightValue = 4000 * (Math.sin(8000 * v) * 0.5 + 0.5); const index = yy * width + xx; buffer[index] = heightValue; } } return buffer; }, } ); Sandcastle.addToolbarMenu( [ { text: “CesiumTerrainProvider – Cesium World Terrain”, onselect: function () { viewer.terrainProvider = worldTerrain; viewer.scene.globe.enableLighting = true; }, }, { text: “CesiumTerrainProvider – Cesium World Terrain – no effects”, onselect: function () { viewer.terrainProvider = Cesium.createWorldTerrain(); }, }, { text: “CesiumTerrainProvider – Cesium World Terrain w/ Lighting”, onselect: function () { viewer.terrainProvider = Cesium.createWorldTerrain({ requestVertexNormals: true, }); viewer.scene.globe.enableLighting = true; }, }, { text: “CesiumTerrainProvider – Cesium World Terrain w/ Water”, onselect: function () { viewer.terrainProvider = Cesium.createWorldTerrain({ requestWaterMask: true, }); }, }, { text: “EllipsoidTerrainProvider”, onselect: function () { viewer.terrainProvider = ellipsoidProvider; }, }, { text: “CustomHeightmapTerrainProvider”, onselect: function () { viewer.terrainProvider = customHeightmapProvider; }, }, { text: “VRTheWorldTerrainProvider”, onselect: function () { viewer.terrainProvider = vrTheWorldProvider; }, }, { text: “ArcGISTerrainProvider”, onselect: function () { viewer.terrainProvider = arcGisProvider; }, }, ], “terrainMenu” ); Sandcastle.addDefaultToolbarMenu( [ { text: “Mount Everest”, onselect: function () { lookAtMtEverest(); }, }, { text: “Half Dome”, onselect: function () { const target = new Cesium.Cartesian3( -2489625.0836225147, -4393941.44443024, 3882535.9454173897 ); const offset = new Cesium.Cartesian3( -6857.40902037546, 412.3284835694358, 2147.5545426812023 ); viewer.camera.lookAt(target, offset); viewer.camera.lookAtTransform(Cesium.Matrix4.IDENTITY); }, }, { text: “San Francisco Bay”, onselect: function () { const target = new Cesium.Cartesian3( -2708814.85583248, -4254159.450845907, 3891403.9457429945 ); const offset = new Cesium.Cartesian3( 70642.66030209465, -31661.517948317807, 35505.179997143336 ); viewer.camera.lookAt(target, offset); viewer.camera.lookAtTransform(Cesium.Matrix4.IDENTITY); }, }, ], “zoomButtons” ); let terrainSamplePositions; function lookAtMtEverest() { const target = new Cesium.Cartesian3( 300770.50872389384, 5634912.131394585, 2978152.2865545116 ); const offset = new Cesium.Cartesian3( 6344.974098678562, -793.3419798081741, 2499.9508860763162 ); viewer.camera.lookAt(target, offset); viewer.camera.lookAtTransform(Cesium.Matrix4.IDENTITY); } function sampleTerrainSuccess(terrainSamplePositions) { const ellipsoid = Cesium.Ellipsoid.WGS84; //By default, Cesium does not obsure geometry //behind terrain. Setting this flag enables that. viewer.scene.globe.depthTestAgainstTerrain = true; viewer.entities.suspendEvents(); viewer.entities.removeAll(); for (let i = 0; i < terrainSamplePositions.length; ++i) { const position = terrainSamplePositions[i]; viewer.entities.add({ name: position.height.toFixed(1), position: ellipsoid.cartographicToCartesian(position), billboard: { verticalOrigin: Cesium.VerticalOrigin.BOTTOM, scale: 0.7, image: “../images/facility.gif”, }, label: { text: position.height.toFixed(1), font: “10pt monospace”, horizontalOrigin: Cesium.HorizontalOrigin.CENTER, pixelOffset: new Cesium.Cartesian2(0, -14), fillColor: Cesium.Color.BLACK, outlineColor: Cesium.Color.BLACK, showBackground: true, backgroundColor: new Cesium.Color(0.9, 0.9, 0.9, 0.7), backgroundPadding: new Cesium.Cartesian2(4, 3), }, }); } viewer.entities.resumeEvents(); } function createGrid(rectangleHalfSize) { const gridWidth = 41; const gridHeight = 41; const everestLatitude = Cesium.Math.toRadians(27.988257); const everestLongitude = Cesium.Math.toRadians(86.925145); const e = new Cesium.Rectangle( everestLongitude – rectangleHalfSize, everestLatitude – rectangleHalfSize, everestLongitude + rectangleHalfSize, everestLatitude + rectangleHalfSize ); const terrainSamplePositions = []; for (let y = 0; y < gridHeight; ++y) { for (let x = 0; x < gridWidth; ++x) { const longitude = Cesium.Math.lerp( e.west, e.east, x / (gridWidth – 1) ); const latitude = Cesium.Math.lerp( e.south, e.north, y / (gridHeight – 1) ); const position = new Cesium.Cartographic(longitude, latitude); terrainSamplePositions.push(position); } } return terrainSamplePositions; } Sandcastle.addToggleButton( “Enable Lighting”, viewer.scene.globe.enableLighting, function (checked) { viewer.scene.globe.enableLighting = checked; } ); Sandcastle.addToggleButton( “Enable fog”, viewer.scene.fog.enabled, function (checked) { viewer.scene.fog.enabled = checked; } ); Sandcastle.addToolbarButton( “Sample Everest Terrain at Level 9”, function () { const terrainSamplePositions = createGrid(0.005); Promise.resolve( Cesium.sampleTerrain( viewer.terrainProvider, 9, terrainSamplePositions ) ).then(sampleTerrainSuccess); lookAtMtEverest(); }, “sampleButtons” ); Sandcastle.addToolbarButton( “Sample Most Detailed Everest Terrain”, function () { if (!Cesium.defined(viewer.terrainProvider.availability)) { window.alert( “sampleTerrainMostDetailed is not supported for the selected terrain provider” ); return; } const terrainSamplePositions = createGrid(0.0005); Promise.resolve( Cesium.sampleTerrainMostDetailed( viewer.terrainProvider, terrainSamplePositions ) ).then(sampleTerrainSuccess); lookAtMtEverest(); }, “sampleButtons” );