/*
 * @Description: 雷达扫描效果
 */
function RadarScan() {
  class RadarScanMaterialProperty {
    constructor(options) {
      this._definitionChanged = new Cesium.Event();
      this._color = undefined;
      this._speed = undefined;
      this.color = options.color;
      this.speed = options.speed;
      this.transparency = options.transparency;
    }

    get isConstant() {
      return false;
    }

    get definitionChanged() {
      return this._definitionChanged;
    }

    getType(time) {
      return Cesium.Material.RadarScanMaterialType;
    }

    getValue(time, result) {
      if (!Cesium.defined(result)) {
        result = {};
      }

      result.color = Cesium.Property.getValueOrDefault(
        this._color,
        time,
        Cesium.Color.RED,
        result.color
      );
      result.speed = Cesium.Property.getValueOrDefault(
        this._speed,
        time,
        10,
        result.speed
      );
      result.transparency = this.transparency;
      result.frameNumber = Cesium.getTimestamp();
      return result;
    }

    equals(other) {
      return (
        this === other ||
        (other instanceof RadarScanMaterialProperty &&
          Cesium.Property.equals(this._color, other._color) &&
          Cesium.Property.equals(this._speed, other._speed) &&
          Cesium.Property.equals(this.transparency, other.transparency))
      );
    }
  }

  Object.defineProperties(RadarScanMaterialProperty.prototype, {
    color: Cesium.createPropertyDescriptor("color"),
    speed: Cesium.createPropertyDescriptor("speed"),
    transparency: Cesium.createPropertyDescriptor("transparency"),
  });

  Cesium.RadarScanMaterialProperty = RadarScanMaterialProperty;
  Cesium.Material.RadarScanMaterialProperty = "RadarScanMaterialProperty";
  Cesium.Material.RadarScanMaterialType = "RadarScanMaterialType";
  Cesium.Material.RadarScanMaterialSource = `
      uniform vec4 color;
      uniform float speed;
      uniform float transparency;
      uniform float frameNumber;
  
      #define PI 3.14159265359
  
      czm_material czm_getMaterial(czm_materialInput materialInput){
      czm_material material = czm_getDefaultMaterial(materialInput);
      vec2 st = materialInput.st;
      vec2 scrPt = st * 2.0 - 1.0;
      float time = frameNumber * speed / 30000.0 ;
      vec3 col = vec3(0.0);
      mat2 rot;
      float theta = -time * 1.0 * PI - 2.2;
      float cosTheta, sinTheta;
      cosTheta = cos(theta);
      sinTheta = sin(theta);
      rot[0][0] = cosTheta;
      rot[0][1] = -sinTheta;
      rot[1][0] = sinTheta;
      rot[1][1] = cosTheta;
      vec2 scrPtRot = rot * scrPt;
      float angle = 1.0 - (atan(scrPtRot.y, scrPtRot.x) / 6.2831 + 0.5);
      float falloff = length(scrPtRot);
      material.alpha = pow(length(col + vec3(.5)),5.0) * transparency * 0.6;
      material.diffuse =  (0.5 +  pow(angle, 2.0) * falloff ) *   color.rgb    ;
      return material;
      }
  
       `;

  Cesium.Material._materialCache.addMaterial(
    Cesium.Material.RadarScanMaterialType,
    {
      fabric: {
        type: Cesium.Material.RadarScanMaterialType,
        uniforms: {
          color: new Cesium.Color(1.0, 0.0, 0.0, 1.0),
          speed: 10.0,
          transparency: 1,
          frameNumber: Cesium.getTimestamp(),
        },
        source: Cesium.Material.RadarScanMaterialSource,
      },
      translucent: function (material) {
        return true;
      },
    }
  );
}

export { RadarScan }