calculate-latest.js

calculateLatest(event) {
    this.latest.t = Date.now();
    this.latest.x = event.offsetX;
    this.latest.y = event.offsetY;

    // time difference
    this.deltaT = this.latest.t - this.initial.t;
    
    // distance traveled
    this.deltaX = Math.abs(this.latest.x - this.initial.x);
    this.deltaY = Math.abs(this.latest.y - this.initial.y);
    this.deltaXY = Math.hypot(this.deltaX, this.deltaY);
    
    // direction of movement
    this.directionX = (this.latest.x - this.initial.x >= 0) ?
        'right' : 'left';
    this.directionY = (this.latest.y - this.initial.y >= 0) ?
        'down' : 'up';
}