toJson method
Converts this object to a JSON-friendly map.
Implementation
@override
Map<String, Object?> toJson() => {
'type': type,
if (id != null) 'id': id,
if (name != null) 'name': name,
'paint': paint.toJson(),
'rotation': rotation,
'locked': locked,
'hidden': hidden,
'x1': x1,
'y1': y1,
'x2': x2,
'y2': y2,
};