update method

@override void update(double dt)

Called before a frame is drawn.

Override this method to do any updates to the node or node tree before it's drawn to screen.

// Make the node rotate at a fixed speed
void update(double dt) {
  rotation = rotation * 10.0 * dt;
}

Implementation

@override
void update(double dt) {
  // Update scrolling position
  if (animationMode == EffectLineAnimationMode.scroll) {
    _offset += dt * scrollSpeed;
    _offset %= 1.0;
  } else if (animationMode == EffectLineAnimationMode.random) {
    _offset = randomDouble();
  }

  // Update age of line points and remove if neccesasry
  if (fadeDuration != null && fadeAfterDelay != null) {
    // Increase age of points
    for (int i = _points.length - 1; i >= 0; i--) {
      _pointAges[i] += dt;
    }

    // Check if the first/oldest point should be removed
    while (_points.isNotEmpty &&
        _pointAges[0] > (fadeDuration! + fadeAfterDelay!)) {
      // Update scroll if it isn't the last and only point that is about to
      // removed
      if (_points.length > 1 && textureLoopLength != null) {
        double dist = GameMath.distanceBetweenPoints(_points[0], _points[1]);
        _offset = (_offset - (dist / textureLoopLength!)) % 1.0;
        if (_offset < 0.0) _offset += 1;
      }

      // Remove the point
      _pointAges.removeAt(0);
      _points.removeAt(0);
    }
  }
}