Method getCanvasFromSVG

src/openlayers/core/StyleUtils.js:967–989

* @function StyleUtils.getCanvasFromSVG * @description 将SVG转换成Canvas * @param {string} svgUrl - 颜色数组 * @param {Object} divDom - div的dom对象 * @param {function} callBack - 转换成功执行的回调函数

(svgUrl, divDom, callBack)

   * @param {function} callBack - 转换成功执行的回调函数
   */
  static async getCanvasFromSVG(svgUrl, divDom, callBack) {
    //一个图层对应一个canvas
    const canvgs = Canvg;
    let canvas = document.createElement('canvas');
    canvas.id = 'dataviz-canvas-' + Util.newGuid(8);
    canvas.style.display = "none";
    divDom.appendChild(canvas);
    try {
      const ctx = canvas.getContext('2d');
      const v = await canvgs.from(ctx, svgUrl, {
        ignoreMouse: true,
        ignoreAnimation: true,
        forceRedraw: () => false
      })
      v.start();
      if (canvas.width > 300 || canvas.height > 300) {
        return;
      }
      callBack(canvas);
    } catch (e) {
      return;
    }
  }

  /**
   * @function StyleUtils.getMarkerDefaultStyle 获取默认标注图层feature的样式