Cesium动态线、水流线效果
// 动态线材质
function PolylineTrailLinkMaterialProperty(color, duration) {
this._definitionChanged = new Cesium.Event();
this._color = undefined;
this._colorSubscription = undefined;
this.color = color;
this.duration = duration;
this._time = (new Date()).getTime();
}
Object.defineProperties(PolylineTrailLinkMaterialProperty.prototype, {
isConstant: {
get: function() {
return false;
}
},
definitionChanged: {
get: function() {
return this._definitionChanged;
}
},
color: Cesium.createPropertyDescriptor('color')
});
PolylineTrailLinkMaterialProperty.prototype.getType = function(time) {
return 'PolylineTrailLink';
}
PolylineTrailLinkMaterialProperty.prototype.getValue = function(time, result) {
if (!Cesium.defined(result)) {
result = {};
}
result.color = Cesium.Property.getValueOrClonedDefault(this._color, time, Cesium.Color.WHITE, result.color);
result.image = Cesium.Material.PolylineTrailLinkImage;
result.time = (((new Date()).getTime() - this._time) % this.duration) / this.duration;
return result;
}
PolylineTrailLinkMaterialProperty.prototype.equals = function(other) {
return this === other ||
(other instanceof PolylineTrailLinkMaterialProperty &&
Cesium.Property.equals(this._color, other._color))
}
Cesium.PolylineTrailLinkMaterialProperty = PolylineTrailLinkMaterialProperty;
Cesium.Material.PolylineTrailLinkType = 'PolylineTrailLink';
Cesium.Material.PolylineTrailLinkImage = "../../static/images/effects/";
Cesium.Material.PolylineTrailLinkSource =...
Cesium.Material._materialCache.addMaterial(Cesium.Material.PolylineTrailLinkType, {
fabric: {
type: Cesium.Material.PolylineTrailLinkType,
uniforms: {
color: new Cesium.Color(1.0, 0.0, 0.0, 0.5),
image: Cesium.Material.PolylineTrailLinkImage,
time: 20
},
source: Cesium.Material.PolylineTrailLinkSource
},
translucent: function(material) {
return true;
}
});
let line = this.viewer.entities.add({
name: 'PolylineTrail',
polyline: {
positions: positions,
width: 8,
material: new Cesium.PolylineTrailLinkMaterialProperty(Cesium.Color.fromCssColorString("#0BFF0D"), 10000),
clampToGround: true
}
});