Method zoom

src/interactions/panZoomInteraction.ts:137–178

* Zooms the chart by a specified amount around a specific point * * @param {number} [zoomAmount] The percentage by which to zoom the x and y scale. * A value of 0.9 zooms in by 10%. A value of 1.1 zooms out by 10%. A value of 1 has * no effect. * @param {Plottable.Point} [centerValue]

(zoomAmount: number, centerValue?: Point, constrained = true)

   * values. Default true.
   */
  public zoom(zoomAmount: number, centerValue?: Point, constrained = true) {
    let centerX: number;
    let centerY: number;
    if (centerValue != null) {
      centerX = centerValue.x;
      centerY = centerValue.y;
      if (constrained) {
        this.xScales().forEach((xScale) => {
          const constrained = this._constrainedZoom(xScale, zoomAmount, centerX);
          centerX = constrained.centerPoint;
          zoomAmount = constrained.zoomAmount;
        });

        this.yScales().forEach((yScale) => {
          const constrained = this._constrainedZoom(yScale, zoomAmount, centerY);
          centerY = constrained.centerPoint;
          zoomAmount = constrained.zoomAmount;
        });
      }
    }

    this.xScales().forEach((xScale) => {
      const range = xScale.range();
      const xCenter = centerX == null
        ? (range[1] + range[0]) / 2
        : centerX;

      xScale.zoom(zoomAmount, xCenter);
    });

    this.yScales().forEach((yScale) => {
      const range = yScale.range();
      const yCenter = centerY == null
        ? (range[1] + range[0]) / 2
        : centerY;

      yScale.zoom(zoomAmount, yCenter);
    });

    this._panZoomUpdateCallbacks.callCallbacks();
    return { zoomAmount, centerValue: { centerX, centerY } };
  }

  protected _anchor(component: Component) {
    super._anchor(component);