cesium添加闪烁点，雷达图（一般用于预警）

最近再做eact-cesium项目来预警了在地图上其经纬度闪烁，找了好久才找到方法（当然是别人封装的）。

 效果图

 /**
     *圆形扩大扫描圈
     * */
    function AddCircleScanPostStage(viewer, cartographicCenter, maxRadius, scanColor, duration) {
        var ScanSegmentShader =
            "uniform sampler2D colorTexture;\n" +
            "uniform sampler2D depthTexture;\n" +
            "varying vec2 v_textureCoordinates;\n" +
            "uniform vec4 u_scanCenterEC;\n" +
            "uniform vec3 u_scanPlaneNormalEC;\n" +
            "uniform float u_radius;\n" +
            "uniform vec4 u_scanColor;\n" +
            "vec4 toEye(in vec2 uv, in float depth)\n" +
            " {\n" +
            " vec2 xy = vec2((uv.x * 2.0 - 1.0),(uv.y * 2.0 - 1.0));\n" +
            " vec4 posInCamera =czm_inverseProjection * vec4(xy, depth, 1.0);\n" +
            " posInCamera =posInCamera / posInCamera.w;\n" +
            " return posInCamera;\n" +
            " }\n" +
            "vec3 pointProjectOnPlane(in vec3 planeNormal, in vec3 planeOrigin, in vec3 point)\n" +
            "{\n" +
            "vec3 v01 = point -planeOrigin;\n" +
            "float d = dot(planeNormal, v01) ;\n" +
            "return (point - planeNormal * d);\n" +
            "}\n" +
            "float getDepth(in vec4 depth)\n" +
            "{\n" +
            "float z_window = czm_unpackDepth(depth);\n" +
            "z_window = czm_reverseLogDepth(z_window);\n" +
            "float n_range = czm_depthRange.near;\n" +
            "float f_range = czm_depthRange.far;\n" +
            "return (2.0 * z_window - n_range - f_range) / (f_range - n_range);\n" +
            "}\n" +
            "void main()\n" +
            "{\n" +
            "gl_FragColor = texture2D(colorTexture, v_textureCoordinates);\n" +
            "float depth = getDepth( texture2D(depthTexture, v_textureCoordinates));\n" +
            "vec4 viewPos = toEye(v_textureCoordinates, depth);\n" +
            "vec3 prjOnPlane = pointProjectOnPlane(u_scanPlaneNormalEC.xyz, u_scanCenterEC.xyz, viewPos.xyz);\n" +
            "float dis = length(prjOnPlane.xyz - u_scanCenterEC.xyz);\n" +
            "if(dis < u_radius)\n" +
            "{\n" +
            "float f = 1.0 -abs(u_radius - dis) / u_radius;\n" +
            "f = pow(f, 4.0);\n" +
            "gl_FragColor = mix(gl_FragColor, u_scanColor, f);\n" +
            "}\n" +
            "}\n";

        var _Cartesian3Center = Cesium.Cartographic.toCartesian(cartographicCenter);
        var _Cartesian4Center = new Cesium.Cartesian4(_Cartesian3Center.x, _Cartesian3Center.y, _Cartesian3Center.z, 1);
        var _CartographicCenter1 = new Cesium.Cartographic(cartographicCenter.longitude, cartographicCenter.latitude, cartographicCenter.height + 500);
        var _Cartesian3Center1 = Cesium.Cartographic.toCartesian(_CartographicCenter1);
        var _Cartesian4Center1 = new Cesium.Cartesian4(_Cartesian3Center1.x, _Cartesian3Center1.y, _Cartesian3Center1.z, 1);
        var _time = (new Date()).getTime();
        var _scratchCartesian4Center = new Cesium.Cartesian4();
        var _scratchCartesian4Center1 = new Cesium.Cartesian4();
        var _scratchCartesian3Normal = new Cesium.Cartesian3();
        var ScanPostStage = new Cesium.PostProcessStage({
            fragmentShader: ScanSegmentShader,
            uniforms: {
                u_scanCenterEC: function () {
                    return Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center, _scratchCartesian4Center);
                },
                u_scanPlaneNormalEC: function () {
                    var temp = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center, _scratchCartesian4Center);
                    var temp1 = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center1, _scratchCartesian4Center1);
                    _scratchCartesian3Normal.x = temp1.x - temp.x;
                    _scratchCartesian3Normal.y = temp1.y - temp.y;
                    _scratchCartesian3Normal.z = temp1.z - temp.z;
                    Cesium.Cartesian3.normalize(_scratchCartesian3Normal, _scratchCartesian3Normal);
                    return _scratchCartesian3Normal;

                },
                u_radius: function () {
                    return maxRadius * (((new Date()).getTime() - _time) % duration) / duration;
                },
                u_scanColor: scanColor
            }
        });
        viewer.scene.postProcessStages.add(ScanPostStage);
        return (ScanPostStage);

    }
    function addCircleScan(viewer,data){
        viewer.scene.globe.depthTestAgainstTerrain = true; //防止移动、放大缩小会视觉偏移depthTestAgainstTerrain // 设置该属性为true之后，标绘将位于地形的顶部；如果设为false（默认值），那么标绘将位于平面上。缺陷：开启该属性有可能在切换图层时会引发标绘消失的bug。
        var CartographicCenter = new Cesium.Cartographic(Cesium.Math.toRadians(data.lon), Cesium.Math.toRadians(data.lat), 0); //中心位子
        return  AddCircleScanPostStage(viewer, CartographicCenter,data.r,data.scanColor,data.interval);
    }

    /**
     *区域雷达扫描
     * */
    function AddRadarScanPostStage(viewer, cartographicCenter, radius, scanColor, duration) {
        var ScanSegmentShader =
            "uniform sampler2D colorTexture;\n" +
            "uniform sampler2D depthTexture;\n" +
            "varying vec2 v_textureCoordinates;\n" +
            "uniform vec4 u_scanCenterEC;\n" +
            "uniform vec3 u_scanPlaneNormalEC;\n" +
            "uniform vec3 u_scanLineNormalEC;\n" +
            "uniform float u_radius;\n" +
            "uniform vec4 u_scanColor;\n" +
            "vec4 toEye(in vec2 uv, in float depth)\n" +
            " {\n" +
            " vec2 xy = vec2((uv.x * 2.0 - 1.0),(uv.y * 2.0 - 1.0));\n" +
            " vec4 posInCamera =czm_inverseProjection * vec4(xy, depth, 1.0);\n" +
            " posInCamera =posInCamera / posInCamera.w;\n" +
            " return posInCamera;\n" +
            " }\n" +
            "bool isPointOnLineRight(in vec3 ptOnLine, in vec3 lineNormal, in vec3 testPt)\n" +
            "{\n" +
            "vec3 v01 = testPt - ptOnLine;\n" +
            "normalize(v01);\n" +
            "vec3 temp = cross(v01, lineNormal);\n" +
            "float d = dot(temp, u_scanPlaneNormalEC);\n" +
            "return d > 0.5;\n" +
            "}\n" +
            "vec3 pointProjectOnPlane(in vec3 planeNormal, in vec3 planeOrigin, in vec3 point)\n" +
            "{\n" +
            "vec3 v01 = point -planeOrigin;\n" +
            "float d = dot(planeNormal, v01) ;\n" +
            "return (point - planeNormal * d);\n" +
            "}\n" +
            "float distancePointToLine(in vec3 ptOnLine, in vec3 lineNormal, in vec3 testPt)\n" +
            "{\n" +
            "vec3 tempPt = pointProjectOnPlane(lineNormal, ptOnLine, testPt);\n" +
            "return length(tempPt - ptOnLine);\n" +
            "}\n" +
            "float getDepth(in vec4 depth)\n" +
            "{\n" +
            "float z_window = czm_unpackDepth(depth);\n" +
            "z_window = czm_reverseLogDepth(z_window);\n" +
            "float n_range = czm_depthRange.near;\n" +
            "float f_range = czm_depthRange.far;\n" +
            "return (2.0 * z_window - n_range - f_range) / (f_range - n_range);\n" +
            "}\n" +
            "void main()\n" +
            "{\n" +
            "gl_FragColor = texture2D(colorTexture, v_textureCoordinates);\n" +
            "float depth = getDepth( texture2D(depthTexture, v_textureCoordinates));\n" +
            "vec4 viewPos = toEye(v_textureCoordinates, depth);\n" +
            "vec3 prjOnPlane = pointProjectOnPlane(u_scanPlaneNormalEC.xyz, u_scanCenterEC.xyz, viewPos.xyz);\n" +
            "float dis = length(prjOnPlane.xyz - u_scanCenterEC.xyz);\n" +
            "float twou_radius = u_radius * 2.0;\n" +
            "if(dis < u_radius)\n" +
            "{\n" +
            "float f0 = 1.0 -abs(u_radius - dis) / u_radius;\n" +
            "f0 = pow(f0, 64.0);\n" +
            "vec3 lineEndPt = vec3(u_scanCenterEC.xyz) + u_scanLineNormalEC * u_radius;\n" +
            "float f = 0.0;\n" +
            "if(isPointOnLineRight(u_scanCenterEC.xyz, u_scanLineNormalEC.xyz, prjOnPlane.xyz))\n" +
            "{\n" +
            "float dis1= length(prjOnPlane.xyz - lineEndPt);\n" +
            "f = abs(twou_radius -dis1) / twou_radius;\n" +
            "f = pow(f, 3.0);\n" +
            "}\n" +
            "gl_FragColor = mix(gl_FragColor, u_scanColor, f + f0);\n" +
            "}\n" +
            "}\n";

        var _Cartesian3Center = Cesium.Cartographic.toCartesian(cartographicCenter);
        var _Cartesian4Center = new Cesium.Cartesian4(_Cartesian3Center.x, _Cartesian3Center.y, _Cartesian3Center.z, 1);
        var _CartographicCenter1 = new Cesium.Cartographic(cartographicCenter.longitude, cartographicCenter.latitude, cartographicCenter.height + 500);
        var _Cartesian3Center1 = Cesium.Cartographic.toCartesian(_CartographicCenter1);
        var _Cartesian4Center1 = new Cesium.Cartesian4(_Cartesian3Center1.x, _Cartesian3Center1.y, _Cartesian3Center1.z, 1);
        var _CartographicCenter2 = new Cesium.Cartographic(cartographicCenter.longitude + Cesium.Math.toRadians(0.001), cartographicCenter.latitude, cartographicCenter.height);
        var _Cartesian3Center2 = Cesium.Cartographic.toCartesian(_CartographicCenter2);
        var _Cartesian4Center2 = new Cesium.Cartesian4(_Cartesian3Center2.x, _Cartesian3Center2.y, _Cartesian3Center2.z, 1);
        var _RotateQ = new Cesium.Quaternion();
        var _RotateM = new Cesium.Matrix3();
        var _time = (new Date()).getTime();
        var _scratchCartesian4Center = new Cesium.Cartesian4();
        var _scratchCartesian4Center1 = new Cesium.Cartesian4();
        var _scratchCartesian4Center2 = new Cesium.Cartesian4();
        var _scratchCartesian3Normal = new Cesium.Cartesian3();
        var _scratchCartesian3Normal1 = new Cesium.Cartesian3();
        var ScanPostStage = new Cesium.PostProcessStage({
            fragmentShader: ScanSegmentShader,
            uniforms: {
                u_scanCenterEC: function () {
                    return Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center, _scratchCartesian4Center);
                },
                u_scanPlaneNormalEC: function () {
                    var temp = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center, _scratchCartesian4Center);
                    var temp1 = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center1, _scratchCartesian4Center1);
                    _scratchCartesian3Normal.x = temp1.x - temp.x;
                    _scratchCartesian3Normal.y = temp1.y - temp.y;
                    _scratchCartesian3Normal.z = temp1.z - temp.z;
                    Cesium.Cartesian3.normalize(_scratchCartesian3Normal, _scratchCartesian3Normal);
                    return _scratchCartesian3Normal;

                },
                u_radius: radius,
                u_scanLineNormalEC: function () {
                    var temp = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center, _scratchCartesian4Center);
                    var temp1 = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center1, _scratchCartesian4Center1);
                    var temp2 = Cesium.Matrix4.multiplyByVector(viewer.camera._viewMatrix, _Cartesian4Center2, _scratchCartesian4Center2);
                    _scratchCartesian3Normal.x = temp1.x - temp.x;
                    _scratchCartesian3Normal.y = temp1.y - temp.y;
                    _scratchCartesian3Normal.z = temp1.z - temp.z;
                    Cesium.Cartesian3.normalize(_scratchCartesian3Normal, _scratchCartesian3Normal);
                    _scratchCartesian3Normal1.x = temp2.x - temp.x;
                    _scratchCartesian3Normal1.y = temp2.y - temp.y;
                    _scratchCartesian3Normal1.z = temp2.z - temp.z;
                    var tempTime = (((new Date()).getTime() - _time) % duration) / duration;
                    Cesium.Quaternion.fromAxisAngle(_scratchCartesian3Normal, tempTime * Cesium.Math.PI * 2, _RotateQ);
                    Cesium.Matrix3.fromQuaternion(_RotateQ, _RotateM);
                    Cesium.Matrix3.multiplyByVector(_RotateM, _scratchCartesian3Normal1, _scratchCartesian3Normal1);
                    Cesium.Cartesian3.normalize(_scratchCartesian3Normal1, _scratchCartesian3Normal1);
                    return _scratchCartesian3Normal1;
                },
                u_scanColor: scanColor
            }
        });
        viewer.scene.postProcessStages.add(ScanPostStage);
        return (ScanPostStage);

    }
    function addRadarScan(viewer,data){
        viewer.scene.globe.depthTestAgainstTerrain = true; //防止移动、放大缩小会视觉偏移depthTestAgainstTerrain // 设置该属性为true之后，标绘将位于地形的顶部；如果设为false（默认值），那么标绘将位于平面上。缺陷：开启该属性有可能在切换图层时会引发标绘消失的bug。
        var CartographicCenter = new Cesium.Cartographic(Cesium.Math.toRadians(data.lon), Cesium.Math.toRadians(data.lat),0); //中心位子
        return  AddRadarScanPostStage(viewer, CartographicCenter,data.r,data.scanColor,data.interval);
    }

只需要调用 addCircleScan方法传入一个viewer和data就行

data:{
 lon:"",//经度
lat:""，//纬度
r:"",//扫描半径
scanColor:"",//颜色注意必须是var scanColor = new Cesium.Color(1.0, 0.0, 0.0, 1);rgba形式的‘red’和‘#fff’都不行
interval:"",//时间
}

可以下载链接: https://pan.baidu.com/s/1EdqlgYD6DHNKGXTvO-7tbg 提取码: pjbe 

来源：CSDN

作者：谷雨521

链接：https://blog.csdn.net/weixin_44058725/article/details/104017509