关于cesium用到的一些方法

在学习cesium时,除了看官方文档外,网上还有很多关于cesium的教程,但也都是基于官方文档的,比如:

三维引擎cesium学习经验
Super洛伽的博客
这系列很不错,有原理篇,也有应用篇法克鸡丝

有了基础教程,就要实际应用起来.下面就是用到的渲染官网信息的方法.

var PipeLine = function() {
//私有成员，存储管道、管件等三维对象
```
this._primitives = new Cesium.PrimitiveCollection();
```
};
//下面声明一个属性，返回私有成员_primitives。该函数需要较新版本浏览器支持
Object.defineProperties(PipeLine.prototype, {
```
Primitives: {
    get: function() {
        return this._primitives;
    }
}
```
});

添加gltf模型(主要是各种类型的管点):

PipeLine.prototype.AddModel = function(pointId, modelUrl, centerPoint, scale) {
var modelMatrix = Cesium.Transforms.eastNorthUpToFixedFrame(centerPoint);
//加入模型列表中
var model = this._primitives.add(Cesium.Model.fromGltf({
    id: pointId,
    //管点id，用于点选
    url: modelUrl,
    modelMatrix: modelMatrix,
    scale: scale
}));
};

添加管道模型:

    function computeCircle(radius) {
    var positions = [];
    for (var i = 0; i < 360; i++) {
        var radians = Cesium.Math.toRadians(i);
        positions.push(new Cesium.Cartesian2(radius * Math.cos(radians), radius * Math.sin(radians)));
    }
    return positions;
};

PipeLine.prototype.addDuandian2 = function (id, x, y, z, x1, y1, z1, w1, color) {
var polylineVolumeGeometry = new Cesium.PolylineVolumeGeometry({
    polylinePositions: Cesium.Cartesian3.fromDegreesArrayHeights([x1, y1, z1 - w1, x, y, z - w1]),
    shapePositions: computeCircle(w1),
});
var polylineInstance = new Cesium.GeometryInstance({
    //标注管线id，用于点选   
    id: id,
    geometry: polylineVolumeGeometry,
    vertexFormat: Cesium.EllipsoidSurfaceAppearance.VERTEX_FORMAT,
    attributes: {
        color: Cesium.ColorGeometryInstanceAttribute.fromColor(color)
    }
});
//加入列表中
this._primitives.add(new Cesium.Primitive({
    geometryInstances: [polylineInstance],
    asynchronous: false,
    appearance: new Cesium.PerInstanceColorAppearance({
        translucent: false,
        closed: true
    })
}));
}