MapGIS Client for JavaScript API

import VisualVariable from './VisualVariable'
import { defaultValue } from '../../../util'
import VisualVariableType from '../../../base/enum/VisualVariableType'
import OpacityStop from './support/OpacityStop'
import { Zondy } from '../../../base'
/**
 * opacity视觉变量
 * @class OpacityVariable
 * @moduleEX RendererModule
 * @param {Object} options 初始化参数
 * @param {Array<OpacityStop>} [options.stops] 透明度分段数组
 * @example 透明度视觉变量的使用方式
 * // 获取layer上renderer对象
 *  const renderer = layer.renderer
 * // 根据FID取值设置透明度
 * // FID取值小于0时，设置符号颜色透明度为0.2
 * // FID取值大于300时 ，设置符号颜色透明度为1.0
 * // FID取值在0-300之间时，显示符号颜色透明度过渡值
 *  renderer.visualVariables = [{
            type: "opacity",
            valueExpression: "$feature.FID",
            stops: [
              {
                opacity: 0.2,
                value: 0,
              },
              {
                opacity: 1.0,
                value:300,
              },
            ],
          }]
 * 
 */
class OpacityVariable extends VisualVariable {
  constructor(options) {
    super(options)
    options = defaultValue(options, {})
    this.type = VisualVariableType.opacity
    /**
     * 透明度分段数组
     * @member {Array<OpacityStop>} OpacityVariable.prototype.stops
     */
    this.stops = defaultValue(options.stops, [])
    this.stops = this.stops.map((v) => OpacityStop.fromJSON(v))
  }

  /**
   * 通过json构造OpacityVariable对象
   * @return {OpacityVariable} json对象
   * */
  static fromJSON(json) {
    return new OpacityVariable(json)
  }

  /**
   * 导出为json对象
   * @return {Object} json对象
   * */
  toJSON() {
    const json = super.toJSON()
    json.type = this.type
    json.normalizationField = this.normalizationField
    json.stops = this.stops.map((v) => v.toJSON())
    return json
  }

  /**
   * 克隆对象
   * @return {OpacityVariable} 克隆后的OpacityVariable对象
   */
  clone() {
    return new OpacityVariable(this.toJSON())
  }
}

Zondy.Renderer.VisualVariable.OpacityVariable = OpacityVariable
export default OpacityVariable