const stepLength = this.props.sliderLength / (this.optionsArray.length - 1);
It works correct when I specify [0, 20, 40, 60, 80, 100]
but it doesn't work correct when I specify [0, 90, 100]

Oh, there is some other issue. The value changes from 0 to 90 when I just moved the marker for 1/4 of the track... Though it's correct because I moved for more then half of the path between two points, but marker must be moved to the target point, otherwise it looks strange