adjustPerspective method

Quality? adjustPerspective(Point<num> mouse, bool click)

Implementation

Quality? adjustPerspective(Point<num> mouse, bool click) {
  //if (click) return null ;
  if (_perspective == null) return null;

  //print('--- adjustPerspective ---');

  Point<num> point = _getMousePointInCanvas(mouse, false);

  var points = _perspective.value ?? _defaultPerspective();

  if (points.length != 4) points = _defaultPerspective();

  var initialBounds = _getPointsBounds(points);

  var target = nearestPoint(points, point)!;
  var targetIdx = points.indexOf(target);

  //print('target: $target #$targetIdx');

  var pointsAdjusted = copyPoints(points);
  pointsAdjusted[targetIdx] = point;

  var bounds = _getPointsBounds(pointsAdjusted);

  if (bounds != initialBounds) {
    var tolerance = max(10, max(width, height) / 50);

    var wDiff = initialBounds.width - bounds.width;
    var hDiff = initialBounds.height - bounds.height;

    var xDiff = target.x - point.x;
    var yDiff = target.y - point.y;

    if (wDiff < 0) wDiff = -wDiff;
    if (hDiff < 0) hDiff = -hDiff;

    if (xDiff < 0) xDiff = -xDiff;
    if (yDiff < 0) yDiff = -yDiff;

    //print('Changing bounds> tolerance: $tolerance > whDiff: $wDiff , $hDiff > xyDiff: $xDiff , $yDiff >> $bounds != $initialBounds') ;

    var pointFixed = point;

    if (xDiff < tolerance && yDiff < tolerance) {
      if (wDiff > 0 && xDiff < yDiff || xDiff < tolerance) {
        pointFixed = Point<num>(target.x, point.y);
      } else if (hDiff > 0 && yDiff < xDiff || yDiff < tolerance) {
        pointFixed = Point<num>(point.x, target.y);
      }
    }

    if (point != pointFixed) {
      pointsAdjusted[targetIdx] = pointFixed;
      bounds = _getPointsBounds(pointsAdjusted);
      point = pointFixed;
    }
  }

  var scaleX = width / bounds.width;
  var scaleY = height / bounds.height;

  //print('scaleX: $scaleX ; scaleY: $scaleY >> $bounds');

  var pointsScaled =
      translatePoints(pointsAdjusted, -bounds.left, -bounds.top);
  pointsScaled = scalePointsXY(pointsScaled, scaleX, scaleY);

  var spaceW = max(5, width / 20);
  var spaceH = max(5, height / 20);

  var pointsInBounds = [
    _boundPoint(pointsScaled[0], Point(0, 0),
        Point(width / 2 - spaceW, height / 2 - spaceH)),
    _boundPoint(pointsScaled[1], Point(width / 2 + spaceW, 0),
        Point(width, height / 2 - spaceH)),
    _boundPoint(pointsScaled[2],
        Point(width / 2 + spaceW, height / 2 + spaceH), Point(width, height)),
    _boundPoint(pointsScaled[3], Point(0, height / 2 + spaceH),
        Point(width / 2 - spaceW, height)),
  ];

  /*
  print('points: $points >> ${_getPointsBounds(points)}');
  print(
      'pointsAdjusted: $pointsAdjusted >> ${_getPointsBounds(pointsAdjusted)}');
  print('pointsScaled: $pointsScaled >> ${_getPointsBounds(pointsScaled)}');
  print(
      'pointsInBounds: $pointsInBounds >> ${_getPointsBounds(pointsInBounds)}');
   */

  _perspective.value = pointsInBounds;

  return Quality.medium;
}