_calcRectDimensionFromPoint(x, y) {
    const canvas = this.getCanvas();
    const canvasWidth = canvas.getWidth();
    const canvasHeight = canvas.getHeight();
    const { x: startX, y: startY } = this._startPoint;
    const { min } = Math;

    const left = min(startX, x);
    const top = min(startY, y);
    const width = clamp(x, startX, canvasWidth) - left; // (startX <= x(mouse) <= canvasWidth) - left
    const height = clamp(y, startY, canvasHeight) - top; // (startY <= y(mouse) <= canvasHeight) - top

    return { left, top, width, height };
  }
Get rect dimension setting from Canvas-Mouse-Position(x, y)
@param {number} x - Canvas-Mouse-Position x
@param {number} y - Canvas-Mouse-Position Y
@returns {{left: number, top: number, width: number, height: number}}
@private