Method scrubStart

script.js:888–950

(ev)

  }

  scrubStart(ev) {
    this.scrubbing = true;
    let rect = this.time_canvas.getBoundingClientRect();
    this.time = ev.offsetX / rect.width * this.total_time;

    window.addEventListener('pointerup', this.scrubEnd.bind(this), {
      once: true
    });

    let y_inc = this.time_canvas.clientHeight / (this.layers.length + 1);
    let y_coord = this.time_canvas.clientHeight;
    let mouseover = false;
    for (let layer of this.layers) {
      y_coord -= y_inc;
      if (layer.start_time > (1.01 * this.time)) {
        continue;
      }
      if (layer.start_time + layer.total_time < (0.99 * this.time)) {
        continue;
      }
      if (Math.abs(ev.offsetY - y_coord) < (0.05 * this.time_canvas.clientHeight)) {
        this.select(layer);
        mouseover = true;
      }
    }

    // can't drag unselected
    if (!this.selected_layer || !mouseover) {
      return;
    }

    // dragging something
    let l = this.selected_layer;

    if (this.intersectsTime(l.start_time)) {
      this.time = l.start_time;
      let base_t = this.time;
      this.dragging = function(t) {
        let diff = t - base_t;
        base_t = t;
        l.start_time += diff;
      }
    } else if (this.intersectsTime(l.start_time + l.total_time)) {
      this.time = l.start_time + l.total_time;
      let base_t = this.time;
      this.dragging = function(t) {
        let diff = t - base_t;
        base_t = t;
        if (l instanceof MoveableLayer) {
          l.adjustTotalTime(diff);
        } else {
          l.start_time += diff;
        }
      }
    } else if (this.time < l.start_time + l.total_time && this.time > l.start_time) {
      let base_t = this.time;
      this.dragging = function(t) {
        let diff = t - base_t;