beveled_rectangle_border.dart 5.32 KB
Newer Older
Ian Hickson's avatar
Ian Hickson committed
1
// Copyright 2014 The Flutter Authors. All rights reserved.
2 3 4 5 6
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:math' as math;

7 8
import 'package:flutter/foundation.dart';

9 10 11 12 13 14 15 16 17 18 19
import 'basic_types.dart';
import 'border_radius.dart';
import 'borders.dart';

/// A rectangular border with flattened or "beveled" corners.
///
/// The line segments that connect the rectangle's four sides will
/// begin and at locations offset by the corresponding border radius,
/// but not farther than the side's center. If all the border radii
/// exceed the sides' half widths/heights the resulting shape is
/// diamond made by connecting the centers of the sides.
20
class BeveledRectangleBorder extends OutlinedBorder {
21 22 23
  /// Creates a border like a [RoundedRectangleBorder] except that the corners
  /// are joined by straight lines instead of arcs.
  const BeveledRectangleBorder({
24
    super.side,
25
    this.borderRadius = BorderRadius.zero,
26
  });
27 28 29 30 31 32 33 34 35 36 37 38 39 40

  /// The radii for each corner.
  ///
  /// Each corner [Radius] defines the endpoints of a line segment that
  /// spans the corner. The endpoints are located in the same place as
  /// they would be for [RoundedRectangleBorder], but they're connected
  /// by a straight line instead of an arc.
  ///
  /// Negative radius values are clamped to 0.0 by [getInnerPath] and
  /// [getOuterPath].
  final BorderRadiusGeometry borderRadius;

  @override
  ShapeBorder scale(double t) {
41
    return BeveledRectangleBorder(
42 43 44 45 46 47
      side: side.scale(t),
      borderRadius: borderRadius * t,
    );
  }

  @override
48
  ShapeBorder? lerpFrom(ShapeBorder? a, double t) {
49
    if (a is BeveledRectangleBorder) {
50
      return BeveledRectangleBorder(
51
        side: BorderSide.lerp(a.side, side, t),
52
        borderRadius: BorderRadiusGeometry.lerp(a.borderRadius, borderRadius, t)!,
53 54 55 56 57 58
      );
    }
    return super.lerpFrom(a, t);
  }

  @override
59
  ShapeBorder? lerpTo(ShapeBorder? b, double t) {
60
    if (b is BeveledRectangleBorder) {
61
      return BeveledRectangleBorder(
62
        side: BorderSide.lerp(side, b.side, t),
63
        borderRadius: BorderRadiusGeometry.lerp(borderRadius, b.borderRadius, t)!,
64 65 66 67 68
      );
    }
    return super.lerpTo(b, t);
  }

69 70 71
  /// Returns a copy of this RoundedRectangleBorder with the given fields
  /// replaced with the new values.
  @override
72
  BeveledRectangleBorder copyWith({ BorderSide? side, BorderRadiusGeometry? borderRadius }) {
73 74 75 76 77 78
    return BeveledRectangleBorder(
      side: side ?? this.side,
      borderRadius: borderRadius ?? this.borderRadius,
    );
  }

79
  Path _getPath(RRect rrect) {
80 81 82 83
    final Offset centerLeft = Offset(rrect.left, rrect.center.dy);
    final Offset centerRight = Offset(rrect.right, rrect.center.dy);
    final Offset centerTop = Offset(rrect.center.dx, rrect.top);
    final Offset centerBottom = Offset(rrect.center.dx, rrect.bottom);
84 85 86 87 88 89 90 91 92 93 94

    final double tlRadiusX = math.max(0.0, rrect.tlRadiusX);
    final double tlRadiusY = math.max(0.0, rrect.tlRadiusY);
    final double trRadiusX = math.max(0.0, rrect.trRadiusX);
    final double trRadiusY = math.max(0.0, rrect.trRadiusY);
    final double blRadiusX = math.max(0.0, rrect.blRadiusX);
    final double blRadiusY = math.max(0.0, rrect.blRadiusY);
    final double brRadiusX = math.max(0.0, rrect.brRadiusX);
    final double brRadiusY = math.max(0.0, rrect.brRadiusY);

    final List<Offset> vertices = <Offset>[
95 96 97 98 99 100 101 102
      Offset(rrect.left, math.min(centerLeft.dy, rrect.top + tlRadiusY)),
      Offset(math.min(centerTop.dx, rrect.left + tlRadiusX), rrect.top),
      Offset(math.max(centerTop.dx, rrect.right -trRadiusX), rrect.top),
      Offset(rrect.right, math.min(centerRight.dy, rrect.top + trRadiusY)),
      Offset(rrect.right, math.max(centerRight.dy, rrect.bottom - brRadiusY)),
      Offset(math.max(centerBottom.dx, rrect.right - brRadiusX), rrect.bottom),
      Offset(math.min(centerBottom.dx, rrect.left + blRadiusX), rrect.bottom),
      Offset(rrect.left, math.max(centerLeft.dy, rrect.bottom  - blRadiusY)),
103 104
    ];

105
    return Path()..addPolygon(vertices, true);
106 107 108
  }

  @override
109
  Path getInnerPath(Rect rect, { TextDirection? textDirection }) {
110
    return _getPath(borderRadius.resolve(textDirection).toRRect(rect).deflate(side.strokeInset));
111 112 113
  }

  @override
114
  Path getOuterPath(Rect rect, { TextDirection? textDirection }) {
115 116 117 118
    return _getPath(borderRadius.resolve(textDirection).toRRect(rect));
  }

  @override
119
  void paint(Canvas canvas, Rect rect, { TextDirection? textDirection }) {
120
    if (rect.isEmpty) {
121
      return;
122
    }
123 124 125 126
    switch (side.style) {
      case BorderStyle.none:
        break;
      case BorderStyle.solid:
127
        final RRect borderRect = borderRadius.resolve(textDirection).toRRect(rect);
128
        final RRect adjustedRect = borderRect.inflate(side.strokeOutset);
129 130
        final Path path = _getPath(adjustedRect)
          ..addPath(getInnerPath(rect, textDirection: textDirection), Offset.zero);
131 132 133 134 135
        canvas.drawPath(path, side.toPaint());
    }
  }

  @override
136
  bool operator ==(Object other) {
137
    if (other.runtimeType != runtimeType) {
138
      return false;
139
    }
140 141 142
    return other is BeveledRectangleBorder
        && other.side == side
        && other.borderRadius == borderRadius;
143 144 145
  }

  @override
146
  int get hashCode => Object.hash(side, borderRadius);
147 148 149

  @override
  String toString() {
150
    return '${objectRuntimeType(this, 'BeveledRectangleBorder')}($side, $borderRadius)';
151 152
  }
}