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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flute/animation.dart';
import 'package:flute/painting.dart';
/// An interpolation between two fractional offsets.
///
/// This class specializes the interpolation of [Tween<FractionalOffset>] to be
/// appropriate for fractional offsets.
///
/// See [Tween] for a discussion on how to use interpolation objects.
///
/// See also:
///
/// * [AlignmentTween], which interpolates between to [Alignment] objects.
class FractionalOffsetTween extends Tween<FractionalOffset?> {
/// Creates a fractional offset tween.
///
/// The [begin] and [end] properties may be null; the null value
/// is treated as meaning the center.
FractionalOffsetTween({ super.begin, super.end });
/// Returns the value this variable has at the given animation clock value.
@override
FractionalOffset? lerp(double t) => FractionalOffset.lerp(begin, end, t);
}
/// An interpolation between two alignments.
///
/// This class specializes the interpolation of [Tween<Alignment>] to be
/// appropriate for alignments.
///
/// See [Tween] for a discussion on how to use interpolation objects.
///
/// See also:
///
/// * [AlignmentGeometryTween], which interpolates between two
/// [AlignmentGeometry] objects.
class AlignmentTween extends Tween<Alignment> {
/// Creates a fractional offset tween.
///
/// The [begin] and [end] properties may be null; the null value
/// is treated as meaning the center.
AlignmentTween({ super.begin, super.end });
/// Returns the value this variable has at the given animation clock value.
@override
Alignment lerp(double t) => Alignment.lerp(begin, end, t)!;
}
/// An interpolation between two [AlignmentGeometry].
///
/// This class specializes the interpolation of [Tween<AlignmentGeometry>]
/// to be appropriate for alignments.
///
/// See [Tween] for a discussion on how to use interpolation objects.
///
/// See also:
///
/// * [AlignmentTween], which interpolates between two [Alignment] objects.
class AlignmentGeometryTween extends Tween<AlignmentGeometry?> {
/// Creates a fractional offset geometry tween.
///
/// The [begin] and [end] properties may be null; the null value
/// is treated as meaning the center.
AlignmentGeometryTween({
super.begin,
super.end,
});
/// Returns the value this variable has at the given animation clock value.
@override
AlignmentGeometry? lerp(double t) => AlignmentGeometry.lerp(begin, end, t);
}