cesium点击拾取坐标
var scene = viewer.scene;
var handler = new Cesium.ScreenSpaceEventHandler(scene.canvas);
//设置鼠标左键单击回调事件
handler.setInputAction(function (e) {
//首先移除之前添加的点
viewer.entities.removeAll();
//获取点击位置笛卡尔坐标
var position = scene.pickPosition(e.position);
//将笛卡尔坐标转化为经纬度坐标
var cartographic = Cesium.Cartographic.fromCartesian(position);
var longitude = Cesium.Math.toDegrees(cartographic.longitude);
var latitude = Cesium.Math.toDegrees(cartographic.latitude);
var height = cartographic.height;
if (height < 0) {
height = 0;
}
//创建弹出框信息
var entity = new Cesium.Entity({
name: "位置信息",
description: createDescription(Cesium, [longitude, latitude, height.toFixed(4)])
});
viewer.selectedEntity = entity;
//在点击位置添加对应点
viewer.entities.add(new Cesium.Entity({
point: new Cesium.PointGraphics({
color: new Cesium.Color(1, 1, 0),
pixelSize: 10,
outlineColor: new Cesium.Color(0, 1, 1),
disableDepthTestDistance:50000 // 添加的点位不被地形遮挡
}),
position: Cesium.Cartesian3.fromDegrees(longitude, latitude, height + 0.5)
}));
}, Cesium.ScreenSpaceEventType.LEFT_CLICK);
//创建描述位置的对话框
function createDescription(Cesium, properties) {
var simpleStyleIdentifiers = ['经度', '纬度', '高度'];
var html = '';
for (var key in properties) {
if (properties.hasOwnProperty(key)) {
if (simpleStyleIdentifiers.indexOf(key) !== -1) {
continue;
}
var value = properties[key];
if (Cesium.defined(value) && value !== '') {
html += '<tr><td>' + simpleStyleIdentifiers[key] + '</td><td>' + value + '</td></tr>';
}
}
}
if (html.length > 0) {
html = '<table class="zebra"><tbody>' + html + '</tbody></table>';
}
return html;
}
cesium设置环境光
让整个场景更亮
- 设置之前：
- 设置之后：
var scene = viewer.scene;
scene.shadowMap.darkness = 1.275;
scene.skyAtmosphere.brightnessShift=0.4;
scene.debugShowFramesPerSecond = true;
scene.hdrEnabled = false;
scene.sun.show = false;
// 设置环境光的强度
scene.lightSource.ambientLightColor = new Cesium.Color(0.98, 0.98, 0.99, 1);
var position1 = new Cesium.Cartesian3.fromDegrees(116.261209157595, 39.3042238956531, 320);
var targetPosition1 = new Cesium.Cartesian3.fromDegrees(116.261209157595, 39.3042238956531,430);
var dirLightOptions = {
targetPosition: targetPosition1,
color: new Cesium.Color(1.0, 1.1, 1.3, 1),
//长条形景观的数据（数据的纹理没有使用烘焙纹理，可以通过光线来制造明暗，排除烘焙的干扰）
intensity: 0.25
};
directionalLight_1 = new Cesium.DirectionalLight(position1, dirLightOptions);
scene.addLightSource(directionalLight_1);
tiles的概念
High-resolution imagery like the first two layers used above is too large to fit into memory or often even a single disk, so imagery is divided into smaller images, called tiles, that can be streamed to a client as needed based on the view.
