69 lines
2.6 KiB
Dart
69 lines
2.6 KiB
Dart
import 'dart:ui';
|
|
|
|
import 'package:aves/widgets/common/magnifier/controller/controller.dart';
|
|
import 'package:aves/widgets/common/magnifier/scale/scale_level.dart';
|
|
import 'package:flutter/foundation.dart';
|
|
|
|
/// Internal class to wrap custom scale boundaries (min, max and initial)
|
|
/// Also, stores values regarding the two sizes: the container and the child.
|
|
class ScaleBoundaries {
|
|
final ScaleLevel _minScale;
|
|
final ScaleLevel _maxScale;
|
|
final ScaleLevel _initialScale;
|
|
final Size viewportSize;
|
|
final Size childSize;
|
|
|
|
const ScaleBoundaries({
|
|
@required ScaleLevel minScale,
|
|
@required ScaleLevel maxScale,
|
|
@required ScaleLevel initialScale,
|
|
@required this.viewportSize,
|
|
@required this.childSize,
|
|
}) : _minScale = minScale,
|
|
_maxScale = maxScale,
|
|
_initialScale = initialScale;
|
|
|
|
double _scaleForLevel(ScaleLevel level) {
|
|
final factor = level.factor;
|
|
switch (level.ref) {
|
|
case ScaleReference.contained:
|
|
return factor * ScaleLevel.scaleForContained(viewportSize, childSize);
|
|
case ScaleReference.covered:
|
|
return factor * ScaleLevel.scaleForCovering(viewportSize, childSize);
|
|
case ScaleReference.absolute:
|
|
default:
|
|
return factor;
|
|
}
|
|
}
|
|
|
|
double get minScale => _scaleForLevel(_minScale);
|
|
|
|
double get maxScale => _scaleForLevel(_maxScale).clamp(minScale, double.infinity);
|
|
|
|
double get initialScale => _scaleForLevel(_initialScale).clamp(minScale, maxScale);
|
|
|
|
Offset get _viewportCenter => viewportSize.center(Offset.zero);
|
|
|
|
Offset get _childCenter => childSize.center(Offset.zero);
|
|
|
|
Offset viewportToStatePosition(MagnifierController controller, Offset viewportPosition) {
|
|
return viewportPosition - _viewportCenter - controller.position;
|
|
}
|
|
|
|
Offset viewportToChildPosition(MagnifierController controller, Offset viewportPosition) {
|
|
return viewportToStatePosition(controller, viewportPosition) / controller.scale + _childCenter;
|
|
}
|
|
|
|
Offset childToStatePosition(double scale, Offset childPosition) {
|
|
return (_childCenter - childPosition) * scale;
|
|
}
|
|
|
|
@override
|
|
bool operator ==(Object other) => identical(this, other) || other is ScaleBoundaries && runtimeType == other.runtimeType && _minScale == other._minScale && _maxScale == other._maxScale && _initialScale == other._initialScale && viewportSize == other.viewportSize && childSize == other.childSize;
|
|
|
|
@override
|
|
int get hashCode => hashValues(_minScale, _maxScale, _initialScale, viewportSize, childSize);
|
|
|
|
@override
|
|
String toString() => '$runtimeType#${shortHash(this)}{viewportSize=$viewportSize, childSize=$childSize, initialScale=$initialScale, minScale=$minScale, maxScale=$maxScale}';
|
|
}
|