cesium/Apps/Sandcastle/gallery/Globe Materials – 3D Tiles ...

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HTML

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta
name="viewport"
content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no"
/>
<meta name="description" content="Apply materials to the globe." />
<meta name="cesium-sandcastle-labels" content="Showcases" />
<title>Cesium Demo</title>
<script type="text/javascript" src="../Sandcastle-header.js"></script>
<script
type="text/javascript"
src="../../../Build/CesiumUnminified/Cesium.js"
nomodule
></script>
<script type="module" src="../load-cesium-es6.js"></script>
</head>
<body class="sandcastle-loading" data-sandcastle-bucket="bucket-requirejs.html">
<style>
@import url(../templates/bucket.css);
</style>
<div id="cesiumContainer" class="fullSize"></div>
<div id="loadingOverlay"><h1>Loading...</h1></div>
<div id="toolbar">
<div id="zoomButtons"></div>
</div>
<script id="cesium_sandcastle_script">
window.startup = async function (Cesium) {
"use strict";
//Sandcastle_Begin
const terrainProvider = await Cesium.Cesium3DTilesTerrainProvider.fromIonAssetId(
3923568,
{
requestVertexNormals: true, // Needed for hillshade lighting
requestWaterMask: true, // Needed to distinguish land from water
},
);
const viewer = new Cesium.Viewer("cesiumContainer", {
terrainProvider: terrainProvider,
scene3DOnly: true,
sceneModePicker: false,
navigationHelpButton: false,
});
// Create a globe material for shading elevation only on land
const customElevationMaterial = new Cesium.Material({
fabric: {
type: "ElevationLand",
materials: {
waterMaskMaterial: {
type: "WaterMask",
},
elevationRampMaterial: {
type: "ElevationRamp",
},
},
components: {
diffuse: "elevationRampMaterial.diffuse",
alpha: "1.0 - waterMaskMaterial.alpha", // We'll need the inverse of the watermask to shade land
},
},
translucent: false,
});
const minHeight = -414.0; // approximate dead sea elevation
const maxHeight = 8777.0; // approximate everest elevation
const elevationRamp = [0.0, 0.045, 0.45, 0.5, 0.55, 1.0];
function getColorRamp() {
const ramp = document.createElement("canvas");
ramp.width = 100;
ramp.height = 1;
const ctx = ramp.getContext("2d");
const values = elevationRamp;
const grd = ctx.createLinearGradient(0, 0, 100, 0);
// See https://gis.stackexchange.com/questions/25099/choosing-colour-ramp-to-use-for-elevation
grd.addColorStop(values[0], "#344f31");
grd.addColorStop(values[1], "#5b8742");
grd.addColorStop(values[2], "#e6daa5");
grd.addColorStop(values[3], "#fdc771");
grd.addColorStop(values[4], "#b99d89");
grd.addColorStop(values[5], "#f0f0f0");
ctx.fillStyle = grd;
ctx.fillRect(0, 0, 100, 1);
return ramp;
}
const globe = viewer.scene.globe;
const material = customElevationMaterial;
const shadingUniforms = material.materials.elevationRampMaterial.uniforms;
globe.showWaterEffect = false;
globe.enableLighting = true;
shadingUniforms.minimumHeight = minHeight;
shadingUniforms.maximumHeight = maxHeight;
shadingUniforms.image = getColorRamp();
globe.material = material;
// Light the scene with a hillshade effect similar to https://pro.arcgis.com/en/pro-app/latest/tool-reference/3d-analyst/how-hillshade-works.htm
const scene = viewer.scene;
scene.light = new Cesium.DirectionalLight({
direction: new Cesium.Cartesian3(1, 0, 0), // Updated every frame
});
// Update the light position base on the camera
const scratchNormal = new Cesium.Cartesian3();
scene.preRender.addEventListener(function (scene, time) {
const surfaceNormal = Cesium.Ellipsoid.WGS84.geodeticSurfaceNormal(
scene.camera.positionWC,
scratchNormal,
);
const negativeNormal = Cesium.Cartesian3.negate(surfaceNormal, surfaceNormal);
scene.light.direction = Cesium.Cartesian3.normalize(
Cesium.Cartesian3.add(negativeNormal, scene.camera.rightWC, surfaceNormal),
scene.light.direction,
);
});
//Sandcastle_End
};
if (typeof Cesium !== "undefined") {
window.startupCalled = true;
window.startup(Cesium).catch((error) => {
"use strict";
console.error(error);
});
Sandcastle.finishedLoading();
}
</script>
</body>
</html>