dart / external / github.com / flutter / engine / 73d18035539934cc9d5ae2b795643e1ae87261bb / . / lib / ui / geometry.dart

// Copyright 2013 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. | |

// @dart = 2.12 | |

part of dart.ui; | |

/// Base class for [Size] and [Offset], which are both ways to describe | |

/// a distance as a two-dimensional axis-aligned vector. | |

abstract class OffsetBase { | |

/// Abstract const constructor. This constructor enables subclasses to provide | |

/// const constructors so that they can be used in const expressions. | |

/// | |

/// The first argument sets the horizontal component, and the second the | |

/// vertical component. | |

const OffsetBase(this._dx, this._dy) | |

: assert(_dx != null), | |

assert(_dy != null); | |

final double _dx; | |

final double _dy; | |

/// Returns true if either component is [double.infinity], and false if both | |

/// are finite (or negative infinity, or NaN). | |

/// | |

/// This is different than comparing for equality with an instance that has | |

/// _both_ components set to [double.infinity]. | |

/// | |

/// See also: | |

/// | |

/// * [isFinite], which is true if both components are finite (and not NaN). | |

bool get isInfinite => _dx >= double.infinity || _dy >= double.infinity; | |

/// Whether both components are finite (neither infinite nor NaN). | |

/// | |

/// See also: | |

/// | |

/// * [isInfinite], which returns true if either component is equal to | |

/// positive infinity. | |

bool get isFinite => _dx.isFinite && _dy.isFinite; | |

/// Less-than operator. Compares an [Offset] or [Size] to another [Offset] or | |

/// [Size], and returns true if both the horizontal and vertical values of the | |

/// left-hand-side operand are smaller than the horizontal and vertical values | |

/// of the right-hand-side operand respectively. Returns false otherwise. | |

/// | |

/// This is a partial ordering. It is possible for two values to be neither | |

/// less, nor greater than, nor equal to, another. | |

bool operator <(OffsetBase other) => _dx < other._dx && _dy < other._dy; | |

/// Less-than-or-equal-to operator. Compares an [Offset] or [Size] to another | |

/// [Offset] or [Size], and returns true if both the horizontal and vertical | |

/// values of the left-hand-side operand are smaller than or equal to the | |

/// horizontal and vertical values of the right-hand-side operand | |

/// respectively. Returns false otherwise. | |

/// | |

/// This is a partial ordering. It is possible for two values to be neither | |

/// less, nor greater than, nor equal to, another. | |

bool operator <=(OffsetBase other) => _dx <= other._dx && _dy <= other._dy; | |

/// Greater-than operator. Compares an [Offset] or [Size] to another [Offset] | |

/// or [Size], and returns true if both the horizontal and vertical values of | |

/// the left-hand-side operand are bigger than the horizontal and vertical | |

/// values of the right-hand-side operand respectively. Returns false | |

/// otherwise. | |

/// | |

/// This is a partial ordering. It is possible for two values to be neither | |

/// less, nor greater than, nor equal to, another. | |

bool operator >(OffsetBase other) => _dx > other._dx && _dy > other._dy; | |

/// Greater-than-or-equal-to operator. Compares an [Offset] or [Size] to | |

/// another [Offset] or [Size], and returns true if both the horizontal and | |

/// vertical values of the left-hand-side operand are bigger than or equal to | |

/// the horizontal and vertical values of the right-hand-side operand | |

/// respectively. Returns false otherwise. | |

/// | |

/// This is a partial ordering. It is possible for two values to be neither | |

/// less, nor greater than, nor equal to, another. | |

bool operator >=(OffsetBase other) => _dx >= other._dx && _dy >= other._dy; | |

/// Equality operator. Compares an [Offset] or [Size] to another [Offset] or | |

/// [Size], and returns true if the horizontal and vertical values of the | |

/// left-hand-side operand are equal to the horizontal and vertical values of | |

/// the right-hand-side operand respectively. Returns false otherwise. | |

@override | |

bool operator ==(Object other) { | |

return other is OffsetBase | |

&& other._dx == _dx | |

&& other._dy == _dy; | |

} | |

@override | |

int get hashCode => hashValues(_dx, _dy); | |

@override | |

String toString() => 'OffsetBase(${_dx.toStringAsFixed(1)}, ${_dy.toStringAsFixed(1)})'; | |

} | |

/// An immutable 2D floating-point offset. | |

/// | |

/// Generally speaking, Offsets can be interpreted in two ways: | |

/// | |

/// 1. As representing a point in Cartesian space a specified distance from a | |

/// separately-maintained origin. For example, the top-left position of | |

/// children in the [RenderBox] protocol is typically represented as an | |

/// [Offset] from the top left of the parent box. | |

/// | |

/// 2. As a vector that can be applied to coordinates. For example, when | |

/// painting a [RenderObject], the parent is passed an [Offset] from the | |

/// screen's origin which it can add to the offsets of its children to find | |

/// the [Offset] from the screen's origin to each of the children. | |

/// | |

/// Because a particular [Offset] can be interpreted as one sense at one time | |

/// then as the other sense at a later time, the same class is used for both | |

/// senses. | |

/// | |

/// See also: | |

/// | |

/// * [Size], which represents a vector describing the size of a rectangle. | |

class Offset extends OffsetBase { | |

/// Creates an offset. The first argument sets [dx], the horizontal component, | |

/// and the second sets [dy], the vertical component. | |

const Offset(double dx, double dy) : super(dx, dy); | |

/// Creates an offset from its [direction] and [distance]. | |

/// | |

/// The direction is in radians clockwise from the positive x-axis. | |

/// | |

/// The distance can be omitted, to create a unit vector (distance = 1.0). | |

factory Offset.fromDirection(double direction, [ double distance = 1.0 ]) { | |

return Offset(distance * math.cos(direction), distance * math.sin(direction)); | |

} | |

/// The x component of the offset. | |

/// | |

/// The y component is given by [dy]. | |

double get dx => _dx; | |

/// The y component of the offset. | |

/// | |

/// The x component is given by [dx]. | |

double get dy => _dy; | |

/// The magnitude of the offset. | |

/// | |

/// If you need this value to compare it to another [Offset]'s distance, | |

/// consider using [distanceSquared] instead, since it is cheaper to compute. | |

double get distance => math.sqrt(dx * dx + dy * dy); | |

/// The square of the magnitude of the offset. | |

/// | |

/// This is cheaper than computing the [distance] itself. | |

double get distanceSquared => dx * dx + dy * dy; | |

/// The angle of this offset as radians clockwise from the positive x-axis, in | |

/// the range -[pi] to [pi], assuming positive values of the x-axis go to the | |

/// right and positive values of the y-axis go down. | |

/// | |

/// Zero means that [dy] is zero and [dx] is zero or positive. | |

/// | |

/// Values from zero to [pi]/2 indicate positive values of [dx] and [dy], the | |

/// bottom-right quadrant. | |

/// | |

/// Values from [pi]/2 to [pi] indicate negative values of [dx] and positive | |

/// values of [dy], the bottom-left quadrant. | |

/// | |

/// Values from zero to -[pi]/2 indicate positive values of [dx] and negative | |

/// values of [dy], the top-right quadrant. | |

/// | |

/// Values from -[pi]/2 to -[pi] indicate negative values of [dx] and [dy], | |

/// the top-left quadrant. | |

/// | |

/// When [dy] is zero and [dx] is negative, the [direction] is [pi]. | |

/// | |

/// When [dx] is zero, [direction] is [pi]/2 if [dy] is positive and -[pi]/2 | |

/// if [dy] is negative. | |

/// | |

/// See also: | |

/// | |

/// * [distance], to compute the magnitude of the vector. | |

/// * [Canvas.rotate], which uses the same convention for its angle. | |

double get direction => math.atan2(dy, dx); | |

/// An offset with zero magnitude. | |

/// | |

/// This can be used to represent the origin of a coordinate space. | |

static const Offset zero = Offset(0.0, 0.0); | |

/// An offset with infinite x and y components. | |

/// | |

/// See also: | |

/// | |

/// * [isInfinite], which checks whether either component is infinite. | |

/// * [isFinite], which checks whether both components are finite. | |

// This is included for completeness, because [Size.infinite] exists. | |

static const Offset infinite = Offset(double.infinity, double.infinity); | |

/// Returns a new offset with the x component scaled by `scaleX` and the y | |

/// component scaled by `scaleY`. | |

/// | |

/// If the two scale arguments are the same, consider using the `*` operator | |

/// instead: | |

/// | |

/// ```dart | |

/// Offset a = const Offset(10.0, 10.0); | |

/// Offset b = a * 2.0; // same as: a.scale(2.0, 2.0) | |

/// ``` | |

/// | |

/// If the two arguments are -1, consider using the unary `-` operator | |

/// instead: | |

/// | |

/// ```dart | |

/// Offset a = const Offset(10.0, 10.0); | |

/// Offset b = -a; // same as: a.scale(-1.0, -1.0) | |

/// ``` | |

Offset scale(double scaleX, double scaleY) => Offset(dx * scaleX, dy * scaleY); | |

/// Returns a new offset with translateX added to the x component and | |

/// translateY added to the y component. | |

/// | |

/// If the arguments come from another [Offset], consider using the `+` or `-` | |

/// operators instead: | |

/// | |

/// ```dart | |

/// Offset a = const Offset(10.0, 10.0); | |

/// Offset b = const Offset(10.0, 10.0); | |

/// Offset c = a + b; // same as: a.translate(b.dx, b.dy) | |

/// Offset d = a - b; // same as: a.translate(-b.dx, -b.dy) | |

/// ``` | |

Offset translate(double translateX, double translateY) => Offset(dx + translateX, dy + translateY); | |

/// Unary negation operator. | |

/// | |

/// Returns an offset with the coordinates negated. | |

/// | |

/// If the [Offset] represents an arrow on a plane, this operator returns the | |

/// same arrow but pointing in the reverse direction. | |

Offset operator -() => Offset(-dx, -dy); | |

/// Binary subtraction operator. | |

/// | |

/// Returns an offset whose [dx] value is the left-hand-side operand's [dx] | |

/// minus the right-hand-side operand's [dx] and whose [dy] value is the | |

/// left-hand-side operand's [dy] minus the right-hand-side operand's [dy]. | |

/// | |

/// See also [translate]. | |

Offset operator -(Offset other) => Offset(dx - other.dx, dy - other.dy); | |

/// Binary addition operator. | |

/// | |

/// Returns an offset whose [dx] value is the sum of the [dx] values of the | |

/// two operands, and whose [dy] value is the sum of the [dy] values of the | |

/// two operands. | |

/// | |

/// See also [translate]. | |

Offset operator +(Offset other) => Offset(dx + other.dx, dy + other.dy); | |

/// Multiplication operator. | |

/// | |

/// Returns an offset whose coordinates are the coordinates of the | |

/// left-hand-side operand (an Offset) multiplied by the scalar | |

/// right-hand-side operand (a double). | |

/// | |

/// See also [scale]. | |

Offset operator *(double operand) => Offset(dx * operand, dy * operand); | |

/// Division operator. | |

/// | |

/// Returns an offset whose coordinates are the coordinates of the | |

/// left-hand-side operand (an Offset) divided by the scalar right-hand-side | |

/// operand (a double). | |

/// | |

/// See also [scale]. | |

Offset operator /(double operand) => Offset(dx / operand, dy / operand); | |

/// Integer (truncating) division operator. | |

/// | |

/// Returns an offset whose coordinates are the coordinates of the | |

/// left-hand-side operand (an Offset) divided by the scalar right-hand-side | |

/// operand (a double), rounded towards zero. | |

Offset operator ~/(double operand) => Offset((dx ~/ operand).toDouble(), (dy ~/ operand).toDouble()); | |

/// Modulo (remainder) operator. | |

/// | |

/// Returns an offset whose coordinates are the remainder of dividing the | |

/// coordinates of the left-hand-side operand (an Offset) by the scalar | |

/// right-hand-side operand (a double). | |

Offset operator %(double operand) => Offset(dx % operand, dy % operand); | |

/// Rectangle constructor operator. | |

/// | |

/// Combines an [Offset] and a [Size] to form a [Rect] whose top-left | |

/// coordinate is the point given by adding this offset, the left-hand-side | |

/// operand, to the origin, and whose size is the right-hand-side operand. | |

/// | |

/// ```dart | |

/// Rect myRect = Offset.zero & const Size(100.0, 100.0); | |

/// // same as: Rect.fromLTWH(0.0, 0.0, 100.0, 100.0) | |

/// ``` | |

Rect operator &(Size other) => Rect.fromLTWH(dx, dy, other.width, other.height); | |

/// Linearly interpolate between two offsets. | |

/// | |

/// If either offset is null, this function interpolates from [Offset.zero]. | |

/// | |

/// The `t` argument represents position on the timeline, with 0.0 meaning | |

/// that the interpolation has not started, returning `a` (or something | |

/// equivalent to `a`), 1.0 meaning that the interpolation has finished, | |

/// returning `b` (or something equivalent to `b`), and values in between | |

/// meaning that the interpolation is at the relevant point on the timeline | |

/// between `a` and `b`. The interpolation can be extrapolated beyond 0.0 and | |

/// 1.0, so negative values and values greater than 1.0 are valid (and can | |

/// easily be generated by curves such as [Curves.elasticInOut]). | |

/// | |

/// Values for `t` are usually obtained from an [Animation<double>], such as | |

/// an [AnimationController]. | |

static Offset? lerp(Offset? a, Offset? b, double t) { | |

assert(t != null); | |

if (b == null) { | |

if (a == null) { | |

return null; | |

} else { | |

return a * (1.0 - t); | |

} | |

} else { | |

if (a == null) { | |

return b * t; | |

} else { | |

return Offset(_lerpDouble(a.dx, b.dx, t), _lerpDouble(a.dy, b.dy, t)); | |

} | |

} | |

} | |

/// Compares two Offsets for equality. | |

@override | |

bool operator ==(Object other) { | |

return other is Offset | |

&& other.dx == dx | |

&& other.dy == dy; | |

} | |

@override | |

int get hashCode => hashValues(dx, dy); | |

@override | |

String toString() => 'Offset(${dx.toStringAsFixed(1)}, ${dy.toStringAsFixed(1)})'; | |

} | |

/// Holds a 2D floating-point size. | |

/// | |

/// You can think of this as an [Offset] from the origin. | |

class Size extends OffsetBase { | |

/// Creates a [Size] with the given [width] and [height]. | |

const Size(double width, double height) : super(width, height); | |

/// Creates an instance of [Size] that has the same values as another. | |

// Used by the rendering library's _DebugSize hack. | |

Size.copy(Size source) : super(source.width, source.height); | |

/// Creates a square [Size] whose [width] and [height] are the given dimension. | |

/// | |

/// See also: | |

/// | |

/// * [Size.fromRadius], which is more convenient when the available size | |

/// is the radius of a circle. | |

const Size.square(double dimension) : super(dimension, dimension); | |

/// Creates a [Size] with the given [width] and an infinite [height]. | |

const Size.fromWidth(double width) : super(width, double.infinity); | |

/// Creates a [Size] with the given [height] and an infinite [width]. | |

const Size.fromHeight(double height) : super(double.infinity, height); | |

/// Creates a square [Size] whose [width] and [height] are twice the given | |

/// dimension. | |

/// | |

/// This is a square that contains a circle with the given radius. | |

/// | |

/// See also: | |

/// | |

/// * [Size.square], which creates a square with the given dimension. | |

const Size.fromRadius(double radius) : super(radius * 2.0, radius * 2.0); | |

/// The horizontal extent of this size. | |

double get width => _dx; | |

/// The vertical extent of this size. | |

double get height => _dy; | |

/// The aspect ratio of this size. | |

/// | |

/// This returns the [width] divided by the [height]. | |

/// | |

/// If the [width] is zero, the result will be zero. If the [height] is zero | |

/// (and the [width] is not), the result will be [double.infinity] or | |

/// [double.negativeInfinity] as determined by the sign of [width]. | |

/// | |

/// See also: | |

/// | |

/// * [AspectRatio], a widget for giving a child widget a specific aspect | |

/// ratio. | |

/// * [FittedBox], a widget that (in most modes) attempts to maintain a | |

/// child widget's aspect ratio while changing its size. | |

double get aspectRatio { | |

if (height != 0.0) | |

return width / height; | |

if (width > 0.0) | |

return double.infinity; | |

if (width < 0.0) | |

return double.negativeInfinity; | |

return 0.0; | |

} | |

/// An empty size, one with a zero width and a zero height. | |

static const Size zero = Size(0.0, 0.0); | |

/// A size whose [width] and [height] are infinite. | |

/// | |

/// See also: | |

/// | |

/// * [isInfinite], which checks whether either dimension is infinite. | |

/// * [isFinite], which checks whether both dimensions are finite. | |

static const Size infinite = Size(double.infinity, double.infinity); | |

/// Whether this size encloses a non-zero area. | |

/// | |

/// Negative areas are considered empty. | |

bool get isEmpty => width <= 0.0 || height <= 0.0; | |

/// Binary subtraction operator for [Size]. | |

/// | |

/// Subtracting a [Size] from a [Size] returns the [Offset] that describes how | |

/// much bigger the left-hand-side operand is than the right-hand-side | |

/// operand. Adding that resulting [Offset] to the [Size] that was the | |

/// right-hand-side operand would return a [Size] equal to the [Size] that was | |

/// the left-hand-side operand. (i.e. if `sizeA - sizeB -> offsetA`, then | |

/// `offsetA + sizeB -> sizeA`) | |

/// | |

/// Subtracting an [Offset] from a [Size] returns the [Size] that is smaller than | |

/// the [Size] operand by the difference given by the [Offset] operand. In other | |

/// words, the returned [Size] has a [width] consisting of the [width] of the | |

/// left-hand-side operand minus the [Offset.dx] dimension of the | |

/// right-hand-side operand, and a [height] consisting of the [height] of the | |

/// left-hand-side operand minus the [Offset.dy] dimension of the | |

/// right-hand-side operand. | |

OffsetBase operator -(OffsetBase other) { | |

if (other is Size) | |

return Offset(width - other.width, height - other.height); | |

if (other is Offset) | |

return Size(width - other.dx, height - other.dy); | |

throw ArgumentError(other); | |

} | |

/// Binary addition operator for adding an [Offset] to a [Size]. | |

/// | |

/// Returns a [Size] whose [width] is the sum of the [width] of the | |

/// left-hand-side operand, a [Size], and the [Offset.dx] dimension of the | |

/// right-hand-side operand, an [Offset], and whose [height] is the sum of the | |

/// [height] of the left-hand-side operand and the [Offset.dy] dimension of | |

/// the right-hand-side operand. | |

Size operator +(Offset other) => Size(width + other.dx, height + other.dy); | |

/// Multiplication operator. | |

/// | |

/// Returns a [Size] whose dimensions are the dimensions of the left-hand-side | |

/// operand (a [Size]) multiplied by the scalar right-hand-side operand (a | |

/// [double]). | |

Size operator *(double operand) => Size(width * operand, height * operand); | |

/// Division operator. | |

/// | |

/// Returns a [Size] whose dimensions are the dimensions of the left-hand-side | |

/// operand (a [Size]) divided by the scalar right-hand-side operand (a | |

/// [double]). | |

Size operator /(double operand) => Size(width / operand, height / operand); | |

/// Integer (truncating) division operator. | |

/// | |

/// Returns a [Size] whose dimensions are the dimensions of the left-hand-side | |

/// operand (a [Size]) divided by the scalar right-hand-side operand (a | |

/// [double]), rounded towards zero. | |

Size operator ~/(double operand) => Size((width ~/ operand).toDouble(), (height ~/ operand).toDouble()); | |

/// Modulo (remainder) operator. | |

/// | |

/// Returns a [Size] whose dimensions are the remainder of dividing the | |

/// left-hand-side operand (a [Size]) by the scalar right-hand-side operand (a | |

/// [double]). | |

Size operator %(double operand) => Size(width % operand, height % operand); | |

/// The lesser of the magnitudes of the [width] and the [height]. | |

double get shortestSide => math.min(width.abs(), height.abs()); | |

/// The greater of the magnitudes of the [width] and the [height]. | |

double get longestSide => math.max(width.abs(), height.abs()); | |

// Convenience methods that do the equivalent of calling the similarly named | |

// methods on a Rect constructed from the given origin and this size. | |

/// The offset to the intersection of the top and left edges of the rectangle | |

/// described by the given [Offset] (which is interpreted as the top-left corner) | |

/// and this [Size]. | |

/// | |

/// See also [Rect.topLeft]. | |

Offset topLeft(Offset origin) => origin; | |

/// The offset to the center of the top edge of the rectangle described by the | |

/// given offset (which is interpreted as the top-left corner) and this size. | |

/// | |

/// See also [Rect.topCenter]. | |

Offset topCenter(Offset origin) => Offset(origin.dx + width / 2.0, origin.dy); | |

/// The offset to the intersection of the top and right edges of the rectangle | |

/// described by the given offset (which is interpreted as the top-left corner) | |

/// and this size. | |

/// | |

/// See also [Rect.topRight]. | |

Offset topRight(Offset origin) => Offset(origin.dx + width, origin.dy); | |

/// The offset to the center of the left edge of the rectangle described by the | |

/// given offset (which is interpreted as the top-left corner) and this size. | |

/// | |

/// See also [Rect.centerLeft]. | |

Offset centerLeft(Offset origin) => Offset(origin.dx, origin.dy + height / 2.0); | |

/// The offset to the point halfway between the left and right and the top and | |

/// bottom edges of the rectangle described by the given offset (which is | |

/// interpreted as the top-left corner) and this size. | |

/// | |

/// See also [Rect.center]. | |

Offset center(Offset origin) => Offset(origin.dx + width / 2.0, origin.dy + height / 2.0); | |

/// The offset to the center of the right edge of the rectangle described by the | |

/// given offset (which is interpreted as the top-left corner) and this size. | |

/// | |

/// See also [Rect.centerLeft]. | |

Offset centerRight(Offset origin) => Offset(origin.dx + width, origin.dy + height / 2.0); | |

/// The offset to the intersection of the bottom and left edges of the | |

/// rectangle described by the given offset (which is interpreted as the | |

/// top-left corner) and this size. | |

/// | |

/// See also [Rect.bottomLeft]. | |

Offset bottomLeft(Offset origin) => Offset(origin.dx, origin.dy + height); | |

/// The offset to the center of the bottom edge of the rectangle described by | |

/// the given offset (which is interpreted as the top-left corner) and this | |

/// size. | |

/// | |

/// See also [Rect.bottomLeft]. | |

Offset bottomCenter(Offset origin) => Offset(origin.dx + width / 2.0, origin.dy + height); | |

/// The offset to the intersection of the bottom and right edges of the | |

/// rectangle described by the given offset (which is interpreted as the | |

/// top-left corner) and this size. | |

/// | |

/// See also [Rect.bottomRight]. | |

Offset bottomRight(Offset origin) => Offset(origin.dx + width, origin.dy + height); | |

/// Whether the point specified by the given offset (which is assumed to be | |

/// relative to the top left of the size) lies between the left and right and | |

/// the top and bottom edges of a rectangle of this size. | |

/// | |

/// Rectangles include their top and left edges but exclude their bottom and | |

/// right edges. | |

bool contains(Offset offset) { | |

return offset.dx >= 0.0 && offset.dx < width && offset.dy >= 0.0 && offset.dy < height; | |

} | |

/// A [Size] with the [width] and [height] swapped. | |

Size get flipped => Size(height, width); | |

/// Linearly interpolate between two sizes | |

/// | |

/// If either size is null, this function interpolates from [Size.zero]. | |

/// | |

/// The `t` argument represents position on the timeline, with 0.0 meaning | |

/// that the interpolation has not started, returning `a` (or something | |

/// equivalent to `a`), 1.0 meaning that the interpolation has finished, | |

/// returning `b` (or something equivalent to `b`), and values in between | |

/// meaning that the interpolation is at the relevant point on the timeline | |

/// between `a` and `b`. The interpolation can be extrapolated beyond 0.0 and | |

/// 1.0, so negative values and values greater than 1.0 are valid (and can | |

/// easily be generated by curves such as [Curves.elasticInOut]). | |

/// | |

/// Values for `t` are usually obtained from an [Animation<double>], such as | |

/// an [AnimationController]. | |

static Size? lerp(Size? a, Size? b, double t) { | |

assert(t != null); | |

if (b == null) { | |

if (a == null) { | |

return null; | |

} else { | |

return a * (1.0 - t); | |

} | |

} else { | |

if (a == null) { | |

return b * t; | |

} else { | |

return Size(_lerpDouble(a.width, b.width, t), _lerpDouble(a.height, b.height, t)); | |

} | |

} | |

} | |

/// Compares two Sizes for equality. | |

// We don't compare the runtimeType because of _DebugSize in the framework. | |

@override | |

bool operator ==(Object other) { | |

return other is Size | |

&& other._dx == _dx | |

&& other._dy == _dy; | |

} | |

@override | |

int get hashCode => hashValues(_dx, _dy); | |

@override | |

String toString() => 'Size(${width.toStringAsFixed(1)}, ${height.toStringAsFixed(1)})'; | |

} | |

/// An immutable, 2D, axis-aligned, floating-point rectangle whose coordinates | |

/// are relative to a given origin. | |

/// | |

/// A Rect can be created with one its constructors or from an [Offset] and a | |

/// [Size] using the `&` operator: | |

/// | |

/// ```dart | |

/// Rect myRect = const Offset(1.0, 2.0) & const Size(3.0, 4.0); | |

/// ``` | |

class Rect { | |

/// Construct a rectangle from its left, top, right, and bottom edges. | |

@pragma('vm:entry-point') | |

const Rect.fromLTRB(this.left, this.top, this.right, this.bottom) | |

: assert(left != null), | |

assert(top != null), | |

assert(right != null), | |

assert(bottom != null); | |

/// Construct a rectangle from its left and top edges, its width, and its | |

/// height. | |

/// | |

/// To construct a [Rect] from an [Offset] and a [Size], you can use the | |

/// rectangle constructor operator `&`. See [Offset.&]. | |

const Rect.fromLTWH(double left, double top, double width, double height) : this.fromLTRB(left, top, left + width, top + height); | |

/// Construct a rectangle that bounds the given circle. | |

/// | |

/// The `center` argument is assumed to be an offset from the origin. | |

Rect.fromCircle({ required Offset center, required double radius }) : this.fromCenter( | |

center: center, | |

width: radius * 2, | |

height: radius * 2, | |

); | |

/// Constructs a rectangle from its center point, width, and height. | |

/// | |

/// The `center` argument is assumed to be an offset from the origin. | |

Rect.fromCenter({ required Offset center, required double width, required double height }) : this.fromLTRB( | |

center.dx - width / 2, | |

center.dy - height / 2, | |

center.dx + width / 2, | |

center.dy + height / 2, | |

); | |

/// Construct the smallest rectangle that encloses the given offsets, treating | |

/// them as vectors from the origin. | |

Rect.fromPoints(Offset a, Offset b) : this.fromLTRB( | |

math.min(a.dx, b.dx), | |

math.min(a.dy, b.dy), | |

math.max(a.dx, b.dx), | |

math.max(a.dy, b.dy), | |

); | |

Float32List get _value32 => Float32List.fromList(<double>[left, top, right, bottom]); | |

/// The offset of the left edge of this rectangle from the x axis. | |

final double left; | |

/// The offset of the top edge of this rectangle from the y axis. | |

final double top; | |

/// The offset of the right edge of this rectangle from the x axis. | |

final double right; | |

/// The offset of the bottom edge of this rectangle from the y axis. | |

final double bottom; | |

/// The distance between the left and right edges of this rectangle. | |

double get width => right - left; | |

/// The distance between the top and bottom edges of this rectangle. | |

double get height => bottom - top; | |

/// The distance between the upper-left corner and the lower-right corner of | |

/// this rectangle. | |

Size get size => Size(width, height); | |

/// Whether any of the dimensions are `NaN`. | |

bool get hasNaN => left.isNaN || top.isNaN || right.isNaN || bottom.isNaN; | |

/// A rectangle with left, top, right, and bottom edges all at zero. | |

static const Rect zero = Rect.fromLTRB(0.0, 0.0, 0.0, 0.0); | |

static const double _giantScalar = 1.0E+9; // matches kGiantRect from layer.h | |

/// A rectangle that covers the entire coordinate space. | |

/// | |

/// This covers the space from -1e9,-1e9 to 1e9,1e9. | |

/// This is the space over which graphics operations are valid. | |

static const Rect largest = Rect.fromLTRB(-_giantScalar, -_giantScalar, _giantScalar, _giantScalar); | |

/// Whether any of the coordinates of this rectangle are equal to positive infinity. | |

// included for consistency with Offset and Size | |

bool get isInfinite { | |

return left >= double.infinity | |

|| top >= double.infinity | |

|| right >= double.infinity | |

|| bottom >= double.infinity; | |

} | |

/// Whether all coordinates of this rectangle are finite. | |

bool get isFinite => left.isFinite && top.isFinite && right.isFinite && bottom.isFinite; | |

/// Whether this rectangle encloses a non-zero area. Negative areas are | |

/// considered empty. | |

bool get isEmpty => left >= right || top >= bottom; | |

/// Returns a new rectangle translated by the given offset. | |

/// | |

/// To translate a rectangle by separate x and y components rather than by an | |

/// [Offset], consider [translate]. | |

Rect shift(Offset offset) { | |

return Rect.fromLTRB(left + offset.dx, top + offset.dy, right + offset.dx, bottom + offset.dy); | |

} | |

/// Returns a new rectangle with translateX added to the x components and | |

/// translateY added to the y components. | |

/// | |

/// To translate a rectangle by an [Offset] rather than by separate x and y | |

/// components, consider [shift]. | |

Rect translate(double translateX, double translateY) { | |

return Rect.fromLTRB(left + translateX, top + translateY, right + translateX, bottom + translateY); | |

} | |

/// Returns a new rectangle with edges moved outwards by the given delta. | |

Rect inflate(double delta) { | |

return Rect.fromLTRB(left - delta, top - delta, right + delta, bottom + delta); | |

} | |

/// Returns a new rectangle with edges moved inwards by the given delta. | |

Rect deflate(double delta) => inflate(-delta); | |

/// Returns a new rectangle that is the intersection of the given | |

/// rectangle and this rectangle. The two rectangles must overlap | |

/// for this to be meaningful. If the two rectangles do not overlap, | |

/// then the resulting Rect will have a negative width or height. | |

Rect intersect(Rect other) { | |

return Rect.fromLTRB( | |

math.max(left, other.left), | |

math.max(top, other.top), | |

math.min(right, other.right), | |

math.min(bottom, other.bottom) | |

); | |

} | |

/// Returns a new rectangle which is the bounding box containing this | |

/// rectangle and the given rectangle. | |

Rect expandToInclude(Rect other) { | |

return Rect.fromLTRB( | |

math.min(left, other.left), | |

math.min(top, other.top), | |

math.max(right, other.right), | |

math.max(bottom, other.bottom), | |

); | |

} | |

/// Whether `other` has a nonzero area of overlap with this rectangle. | |

bool overlaps(Rect other) { | |

if (right <= other.left || other.right <= left) | |

return false; | |

if (bottom <= other.top || other.bottom <= top) | |

return false; | |

return true; | |

} | |

/// The lesser of the magnitudes of the [width] and the [height] of this | |

/// rectangle. | |

double get shortestSide => math.min(width.abs(), height.abs()); | |

/// The greater of the magnitudes of the [width] and the [height] of this | |

/// rectangle. | |

double get longestSide => math.max(width.abs(), height.abs()); | |

/// The offset to the intersection of the top and left edges of this rectangle. | |

/// | |

/// See also [Size.topLeft]. | |

Offset get topLeft => Offset(left, top); | |

/// The offset to the center of the top edge of this rectangle. | |

/// | |

/// See also [Size.topCenter]. | |

Offset get topCenter => Offset(left + width / 2.0, top); | |

/// The offset to the intersection of the top and right edges of this rectangle. | |

/// | |

/// See also [Size.topRight]. | |

Offset get topRight => Offset(right, top); | |

/// The offset to the center of the left edge of this rectangle. | |

/// | |

/// See also [Size.centerLeft]. | |

Offset get centerLeft => Offset(left, top + height / 2.0); | |

/// The offset to the point halfway between the left and right and the top and | |

/// bottom edges of this rectangle. | |

/// | |

/// See also [Size.center]. | |

Offset get center => Offset(left + width / 2.0, top + height / 2.0); | |

/// The offset to the center of the right edge of this rectangle. | |

/// | |

/// See also [Size.centerLeft]. | |

Offset get centerRight => Offset(right, top + height / 2.0); | |

/// The offset to the intersection of the bottom and left edges of this rectangle. | |

/// | |

/// See also [Size.bottomLeft]. | |

Offset get bottomLeft => Offset(left, bottom); | |

/// The offset to the center of the bottom edge of this rectangle. | |

/// | |

/// See also [Size.bottomLeft]. | |

Offset get bottomCenter => Offset(left + width / 2.0, bottom); | |

/// The offset to the intersection of the bottom and right edges of this rectangle. | |

/// | |

/// See also [Size.bottomRight]. | |

Offset get bottomRight => Offset(right, bottom); | |

/// Whether the point specified by the given offset (which is assumed to be | |

/// relative to the origin) lies between the left and right and the top and | |

/// bottom edges of this rectangle. | |

/// | |

/// Rectangles include their top and left edges but exclude their bottom and | |

/// right edges. | |

bool contains(Offset offset) { | |

return offset.dx >= left && offset.dx < right && offset.dy >= top && offset.dy < bottom; | |

} | |

/// Linearly interpolate between two rectangles. | |

/// | |

/// If either rect is null, [Rect.zero] is used as a substitute. | |

/// | |

/// The `t` argument represents position on the timeline, with 0.0 meaning | |

/// that the interpolation has not started, returning `a` (or something | |

/// equivalent to `a`), 1.0 meaning that the interpolation has finished, | |

/// returning `b` (or something equivalent to `b`), and values in between | |

/// meaning that the interpolation is at the relevant point on the timeline | |

/// between `a` and `b`. The interpolation can be extrapolated beyond 0.0 and | |

/// 1.0, so negative values and values greater than 1.0 are valid (and can | |

/// easily be generated by curves such as [Curves.elasticInOut]). | |

/// | |

/// Values for `t` are usually obtained from an [Animation<double>], such as | |

/// an [AnimationController]. | |

static Rect? lerp(Rect? a, Rect? b, double t) { | |

assert(t != null); | |

if (b == null) { | |

if (a == null) { | |

return null; | |

} else { | |

final double k = 1.0 - t; | |

return Rect.fromLTRB(a.left * k, a.top * k, a.right * k, a.bottom * k); | |

} | |

} else { | |

if (a == null) { | |

return Rect.fromLTRB(b.left * t, b.top * t, b.right * t, b.bottom * t); | |

} else { | |

return Rect.fromLTRB( | |

_lerpDouble(a.left, b.left, t), | |

_lerpDouble(a.top, b.top, t), | |

_lerpDouble(a.right, b.right, t), | |

_lerpDouble(a.bottom, b.bottom, t), | |

); | |

} | |

} | |

} | |

@override | |

bool operator ==(Object other) { | |

if (identical(this, other)) | |

return true; | |

if (runtimeType != other.runtimeType) | |

return false; | |

return other is Rect | |

&& other.left == left | |

&& other.top == top | |

&& other.right == right | |

&& other.bottom == bottom; | |

} | |

@override | |

int get hashCode => hashValues(left, top, right, bottom); | |

@override | |

String toString() => 'Rect.fromLTRB(${left.toStringAsFixed(1)}, ${top.toStringAsFixed(1)}, ${right.toStringAsFixed(1)}, ${bottom.toStringAsFixed(1)})'; | |

} | |

/// A radius for either circular or elliptical shapes. | |

class Radius { | |

/// Constructs a circular radius. [x] and [y] will have the same radius value. | |

const Radius.circular(double radius) : this.elliptical(radius, radius); | |

/// Constructs an elliptical radius with the given radii. | |

const Radius.elliptical(this.x, this.y); | |

/// The radius value on the horizontal axis. | |

final double x; | |

/// The radius value on the vertical axis. | |

final double y; | |

/// A radius with [x] and [y] values set to zero. | |

/// | |

/// You can use [Radius.zero] with [RRect] to have right-angle corners. | |

static const Radius zero = Radius.circular(0.0); | |

/// Unary negation operator. | |

/// | |

/// Returns a Radius with the distances negated. | |

/// | |

/// Radiuses with negative values aren't geometrically meaningful, but could | |

/// occur as part of expressions. For example, negating a radius of one pixel | |

/// and then adding the result to another radius is equivalent to subtracting | |

/// a radius of one pixel from the other. | |

Radius operator -() => Radius.elliptical(-x, -y); | |

/// Binary subtraction operator. | |

/// | |

/// Returns a radius whose [x] value is the left-hand-side operand's [x] | |

/// minus the right-hand-side operand's [x] and whose [y] value is the | |

/// left-hand-side operand's [y] minus the right-hand-side operand's [y]. | |

Radius operator -(Radius other) => Radius.elliptical(x - other.x, y - other.y); | |

/// Binary addition operator. | |

/// | |

/// Returns a radius whose [x] value is the sum of the [x] values of the | |

/// two operands, and whose [y] value is the sum of the [y] values of the | |

/// two operands. | |

Radius operator +(Radius other) => Radius.elliptical(x + other.x, y + other.y); | |

/// Multiplication operator. | |

/// | |

/// Returns a radius whose coordinates are the coordinates of the | |

/// left-hand-side operand (a radius) multiplied by the scalar | |

/// right-hand-side operand (a double). | |

Radius operator *(double operand) => Radius.elliptical(x * operand, y * operand); | |

/// Division operator. | |

/// | |

/// Returns a radius whose coordinates are the coordinates of the | |

/// left-hand-side operand (a radius) divided by the scalar right-hand-side | |

/// operand (a double). | |

Radius operator /(double operand) => Radius.elliptical(x / operand, y / operand); | |

/// Integer (truncating) division operator. | |

/// | |

/// Returns a radius whose coordinates are the coordinates of the | |

/// left-hand-side operand (a radius) divided by the scalar right-hand-side | |

/// operand (a double), rounded towards zero. | |

Radius operator ~/(double operand) => Radius.elliptical((x ~/ operand).toDouble(), (y ~/ operand).toDouble()); | |

/// Modulo (remainder) operator. | |

/// | |

/// Returns a radius whose coordinates are the remainder of dividing the | |

/// coordinates of the left-hand-side operand (a radius) by the scalar | |

/// right-hand-side operand (a double). | |

Radius operator %(double operand) => Radius.elliptical(x % operand, y % operand); | |

/// Linearly interpolate between two radii. | |

/// | |

/// If either is null, this function substitutes [Radius.zero] instead. | |

/// | |

/// The `t` argument represents position on the timeline, with 0.0 meaning | |

/// that the interpolation has not started, returning `a` (or something | |

/// equivalent to `a`), 1.0 meaning that the interpolation has finished, | |

/// returning `b` (or something equivalent to `b`), and values in between | |

/// meaning that the interpolation is at the relevant point on the timeline | |

/// between `a` and `b`. The interpolation can be extrapolated beyond 0.0 and | |

/// 1.0, so negative values and values greater than 1.0 are valid (and can | |

/// easily be generated by curves such as [Curves.elasticInOut]). | |

/// | |

/// Values for `t` are usually obtained from an [Animation<double>], such as | |

/// an [AnimationController]. | |

static Radius? lerp(Radius? a, Radius? b, double t) { | |

assert(t != null); | |

if (b == null) { | |

if (a == null) { | |

return null; | |

} else { | |

final double k = 1.0 - t; | |

return Radius.elliptical(a.x * k, a.y * k); | |

} | |

} else { | |

if (a == null) { | |

return Radius.elliptical(b.x * t, b.y * t); | |

} else { | |

return Radius.elliptical( | |

_lerpDouble(a.x, b.x, t), | |

_lerpDouble(a.y, b.y, t), | |

); | |

} | |

} | |

} | |

@override | |

bool operator ==(Object other) { | |

if (identical(this, other)) | |

return true; | |

if (runtimeType != other.runtimeType) | |

return false; | |

return other is Radius | |

&& other.x == x | |

&& other.y == y; | |

} | |

@override | |

int get hashCode => hashValues(x, y); | |

@override | |

String toString() { | |

return x == y ? 'Radius.circular(${x.toStringAsFixed(1)})' : | |

'Radius.elliptical(${x.toStringAsFixed(1)}, ' | |

'${y.toStringAsFixed(1)})'; | |

} | |

} | |

/// An immutable rounded rectangle with the custom radii for all four corners. | |

class RRect { | |

/// Construct a rounded rectangle from its left, top, right, and bottom edges, | |

/// and the same radii along its horizontal axis and its vertical axis. | |

const RRect.fromLTRBXY(double left, double top, double right, double bottom, | |

double radiusX, double radiusY) : this._raw( | |

top: top, | |

left: left, | |

right: right, | |

bottom: bottom, | |

tlRadiusX: radiusX, | |

tlRadiusY: radiusY, | |

trRadiusX: radiusX, | |

trRadiusY: radiusY, | |

blRadiusX: radiusX, | |

blRadiusY: radiusY, | |

brRadiusX: radiusX, | |

brRadiusY: radiusY, | |

); | |

/// Construct a rounded rectangle from its left, top, right, and bottom edges, | |

/// and the same radius in each corner. | |

RRect.fromLTRBR(double left, double top, double right, double bottom, | |

Radius radius) | |

: this._raw( | |

top: top, | |

left: left, | |

right: right, | |

bottom: bottom, | |

tlRadiusX: radius.x, | |

tlRadiusY: radius.y, | |

trRadiusX: radius.x, | |

trRadiusY: radius.y, | |

blRadiusX: radius.x, | |

blRadiusY: radius.y, | |

brRadiusX: radius.x, | |

brRadiusY: radius.y, | |

); | |

/// Construct a rounded rectangle from its bounding box and the same radii | |

/// along its horizontal axis and its vertical axis. | |

RRect.fromRectXY(Rect rect, double radiusX, double radiusY) | |

: this._raw( | |

top: rect.top, | |

left: rect.left, | |

right: rect.right, | |

bottom: rect.bottom, | |

tlRadiusX: radiusX, | |

tlRadiusY: radiusY, | |

trRadiusX: radiusX, | |

trRadiusY: radiusY, | |

blRadiusX: radiusX, | |

blRadiusY: radiusY, | |

brRadiusX: radiusX, | |

brRadiusY: radiusY, | |

); | |

/// Construct a rounded rectangle from its bounding box and a radius that is | |

/// the same in each corner. | |

RRect.fromRectAndRadius(Rect rect, Radius radius) | |

: this._raw( | |

top: rect.top, | |

left: rect.left, | |

right: rect.right, | |

bottom: rect.bottom, | |

tlRadiusX: radius.x, | |

tlRadiusY: radius.y, | |

trRadiusX: radius.x, | |

trRadiusY: radius.y, | |

blRadiusX: radius.x, | |

blRadiusY: radius.y, | |

brRadiusX: radius.x, | |

brRadiusY: radius.y, | |

); | |

/// Construct a rounded rectangle from its left, top, right, and bottom edges, | |

/// and topLeft, topRight, bottomRight, and bottomLeft radii. | |

/// | |

/// The corner radii default to [Radius.zero], i.e. right-angled corners. | |

RRect.fromLTRBAndCorners( | |

double left, | |

double top, | |

double right, | |

double bottom, { | |

Radius topLeft = Radius.zero, | |

Radius topRight = Radius.zero, | |

Radius bottomRight = Radius.zero, | |

Radius bottomLeft = Radius.zero, | |

}) : this._raw( | |

top: top, | |

left: left, | |

right: right, | |

bottom: bottom, | |

tlRadiusX: topLeft.x, | |

tlRadiusY: topLeft.y, | |

trRadiusX: topRight.x, | |

trRadiusY: topRight.y, | |

blRadiusX: bottomLeft.x, | |

blRadiusY: bottomLeft.y, | |

brRadiusX: bottomRight.x, | |

brRadiusY: bottomRight.y, | |

); | |

/// Construct a rounded rectangle from its bounding box and and topLeft, | |

/// topRight, bottomRight, and bottomLeft radii. | |

/// | |

/// The corner radii default to [Radius.zero], i.e. right-angled corners | |

RRect.fromRectAndCorners( | |

Rect rect, | |

{ | |

Radius topLeft = Radius.zero, | |

Radius topRight = Radius.zero, | |

Radius bottomRight = Radius.zero, | |

Radius bottomLeft = Radius.zero | |

} | |

) : this._raw( | |

top: rect.top, | |

left: rect.left, | |

right: rect.right, | |

bottom: rect.bottom, | |

tlRadiusX: topLeft.x, | |

tlRadiusY: topLeft.y, | |

trRadiusX: topRight.x, | |

trRadiusY: topRight.y, | |

blRadiusX: bottomLeft.x, | |

blRadiusY: bottomLeft.y, | |

brRadiusX: bottomRight.x, | |

brRadiusY: bottomRight.y, | |

); | |

const RRect._raw({ | |

this.left = 0.0, | |

this.top = 0.0, | |

this.right = 0.0, | |

this.bottom = 0.0, | |

this.tlRadiusX = 0.0, | |

this.tlRadiusY = 0.0, | |

this.trRadiusX = 0.0, | |

this.trRadiusY = 0.0, | |

this.brRadiusX = 0.0, | |

this.brRadiusY = 0.0, | |

this.blRadiusX = 0.0, | |

this.blRadiusY = 0.0, | |

}) : assert(left != null), | |

assert(top != null), | |

assert(right != null), | |

assert(bottom != null), | |

assert(tlRadiusX != null), | |

assert(tlRadiusY != null), | |

assert(trRadiusX != null), | |

assert(trRadiusY != null), | |

assert(brRadiusX != null), | |

assert(brRadiusY != null), | |

assert(blRadiusX != null), | |

assert(blRadiusY != null); | |

Float32List get _value32 => Float32List.fromList(<double>[ | |

left, | |

top, | |

right, | |

bottom, | |

tlRadiusX, | |

tlRadiusY, | |

trRadiusX, | |

trRadiusY, | |

brRadiusX, | |

brRadiusY, | |

blRadiusX, | |

blRadiusY, | |

]); | |

/// The offset of the left edge of this rectangle from the x axis. | |

final double left; | |

/// The offset of the top edge of this rectangle from the y axis. | |

final double top; | |

/// The offset of the right edge of this rectangle from the x axis. | |

final double right; | |

/// The offset of the bottom edge of this rectangle from the y axis. | |

final double bottom; | |

/// The top-left horizontal radius. | |

final double tlRadiusX; | |

/// The top-left vertical radius. | |

final double tlRadiusY; | |

/// The top-left [Radius]. | |

Radius get tlRadius => Radius.elliptical(tlRadiusX, tlRadiusY); | |

/// The top-right horizontal radius. | |

final double trRadiusX; | |

/// The top-right vertical radius. | |

final double trRadiusY; | |

/// The top-right [Radius]. | |

Radius get trRadius => Radius.elliptical(trRadiusX, trRadiusY); | |

/// The bottom-right horizontal radius. | |

final double brRadiusX; | |

/// The bottom-right vertical radius. | |

final double brRadiusY; | |

/// The bottom-right [Radius]. | |

Radius get brRadius => Radius.elliptical(brRadiusX, brRadiusY); | |

/// The bottom-left horizontal radius. | |

final double blRadiusX; | |

/// The bottom-left vertical radius. | |

final double blRadiusY; | |

/// The bottom-left [Radius]. | |

Radius get blRadius => Radius.elliptical(blRadiusX, blRadiusY); | |

/// A rounded rectangle with all the values set to zero. | |

static const RRect zero = RRect._raw(); | |

/// Returns a new [RRect] translated by the given offset. | |

RRect shift(Offset offset) { | |

return RRect._raw( | |

left: left + offset.dx, | |

top: top + offset.dy, | |

right: right + offset.dx, | |

bottom: bottom + offset.dy, | |

tlRadiusX: tlRadiusX, | |

tlRadiusY: tlRadiusY, | |

trRadiusX: trRadiusX, | |

trRadiusY: trRadiusY, | |

blRadiusX: blRadiusX, | |

blRadiusY: blRadiusY, | |

brRadiusX: brRadiusX, | |

brRadiusY: brRadiusY, | |

); | |

} | |

/// Returns a new [RRect] with edges and radii moved outwards by the given | |

/// delta. | |

RRect inflate(double delta) { | |

return RRect._raw( | |

left: left - delta, | |

top: top - delta, | |

right: right + delta, | |

bottom: bottom + delta, | |

tlRadiusX: tlRadiusX + delta, | |

tlRadiusY: tlRadiusY + delta, | |

trRadiusX: trRadiusX + delta, | |

trRadiusY: trRadiusY + delta, | |

blRadiusX: blRadiusX + delta, | |

blRadiusY: blRadiusY + delta, | |

brRadiusX: brRadiusX + delta, | |

brRadiusY: brRadiusY + delta, | |

); | |

} | |

/// Returns a new [RRect] with edges and radii moved inwards by the given delta. | |

RRect deflate(double delta) => inflate(-delta); | |

/// The distance between the left and right edges of this rectangle. | |

double get width => right - left; | |

/// The distance between the top and bottom edges of this rectangle. | |

double get height => bottom - top; | |

/// The bounding box of this rounded rectangle (the rectangle with no rounded corners). | |

Rect get outerRect => Rect.fromLTRB(left, top, right, bottom); | |

/// The non-rounded rectangle that is constrained by the smaller of the two | |

/// diagonals, with each diagonal traveling through the middle of the curve | |

/// corners. The middle of a corner is the intersection of the curve with its | |

/// respective quadrant bisector. | |

Rect get safeInnerRect { | |

const double kInsetFactor = 0.29289321881; // 1-cos(pi/4) | |

final double leftRadius = math.max(blRadiusX, tlRadiusX); | |

final double topRadius = math.max(tlRadiusY, trRadiusY); | |

final double rightRadius = math.max(trRadiusX, brRadiusX); | |

final double bottomRadius = math.max(brRadiusY, blRadiusY); | |

return Rect.fromLTRB( | |

left + leftRadius * kInsetFactor, | |

top + topRadius * kInsetFactor, | |

right - rightRadius * kInsetFactor, | |

bottom - bottomRadius * kInsetFactor | |

); | |

} | |

/// The rectangle that would be formed using the axis-aligned intersection of | |

/// the sides of the rectangle, i.e., the rectangle formed from the | |

/// inner-most centers of the ellipses that form the corners. This is the | |

/// intersection of the [wideMiddleRect] and the [tallMiddleRect]. If any of | |

/// the intersections are void, the resulting [Rect] will have negative width | |

/// or height. | |

Rect get middleRect { | |

final double leftRadius = math.max(blRadiusX, tlRadiusX); | |

final double topRadius = math.max(tlRadiusY, trRadiusY); | |

final double rightRadius = math.max(trRadiusX, brRadiusX); | |

final double bottomRadius = math.max(brRadiusY, blRadiusY); | |

return Rect.fromLTRB( | |

left + leftRadius, | |

top + topRadius, | |

right - rightRadius, | |

bottom - bottomRadius | |

); | |

} | |

/// The biggest rectangle that is entirely inside the rounded rectangle and | |

/// has the full width of the rounded rectangle. If the rounded rectangle does | |

/// not have an axis-aligned intersection of its left and right side, the | |

/// resulting [Rect] will have negative width or height. | |

Rect get wideMiddleRect { | |

final double topRadius = math.max(tlRadiusY, trRadiusY); | |

final double bottomRadius = math.max(brRadiusY, blRadiusY); | |

return Rect.fromLTRB( | |

left, | |

top + topRadius, | |

right, | |

bottom - bottomRadius | |

); | |

} | |

/// The biggest rectangle that is entirely inside the rounded rectangle and | |

/// has the full height of the rounded rectangle. If the rounded rectangle | |

/// does not have an axis-aligned intersection of its top and bottom side, the | |

/// resulting [Rect] will have negative width or height. | |

Rect get tallMiddleRect { | |

final double leftRadius = math.max(blRadiusX, tlRadiusX); | |

final double rightRadius = math.max(trRadiusX, brRadiusX); | |

return Rect.fromLTRB( | |

left + leftRadius, | |

top, | |

right - rightRadius, | |

bottom | |

); | |

} | |

/// Whether this rounded rectangle encloses a non-zero area. | |

/// Negative areas are considered empty. | |

bool get isEmpty => left >= right || top >= bottom; | |

/// Whether all coordinates of this rounded rectangle are finite. | |

bool get isFinite => left.isFinite && top.isFinite && right.isFinite && bottom.isFinite; | |

/// Whether this rounded rectangle is a simple rectangle with zero | |

/// corner radii. | |

bool get isRect { | |

return (tlRadiusX == 0.0 || tlRadiusY == 0.0) && | |

(trRadiusX == 0.0 || trRadiusY == 0.0) && | |

(blRadiusX == 0.0 || blRadiusY == 0.0) && | |

(brRadiusX == 0.0 || brRadiusY == 0.0); | |

} | |

/// Whether this rounded rectangle has a side with no straight section. | |

bool get isStadium { | |

return tlRadius == trRadius | |

&& trRadius == brRadius | |

&& brRadius == blRadius | |

&& (width <= 2.0 * tlRadiusX || height <= 2.0 * tlRadiusY); | |

} | |

/// Whether this rounded rectangle has no side with a straight section. | |

bool get isEllipse { | |

return tlRadius == trRadius | |

&& trRadius == brRadius | |

&& brRadius == blRadius | |

&& width <= 2.0 * tlRadiusX | |

&& height <= 2.0 * tlRadiusY; | |

} | |

/// Whether this rounded rectangle would draw as a circle. | |

bool get isCircle => width == height && isEllipse; | |

/// The lesser of the magnitudes of the [width] and the [height] of this | |

/// rounded rectangle. | |

double get shortestSide => math.min(width.abs(), height.abs()); | |

/// The greater of the magnitudes of the [width] and the [height] of this | |

/// rounded rectangle. | |

double get longestSide => math.max(width.abs(), height.abs()); | |

/// Whether any of the dimensions are `NaN`. | |

bool get hasNaN => left.isNaN || top.isNaN || right.isNaN || bottom.isNaN || | |

trRadiusX.isNaN || trRadiusY.isNaN || tlRadiusX.isNaN || tlRadiusY.isNaN || | |

brRadiusX.isNaN || brRadiusY.isNaN || blRadiusX.isNaN || blRadiusY.isNaN; | |

/// The offset to the point halfway between the left and right and the top and | |

/// bottom edges of this rectangle. | |

Offset get center => Offset(left + width / 2.0, top + height / 2.0); | |

// Returns the minimum between min and scale to which radius1 and radius2 | |

// should be scaled with in order not to exceed the limit. | |

double _getMin(double min, double radius1, double radius2, double limit) { | |

final double sum = radius1 + radius2; | |

if (sum > limit && sum != 0.0) | |

return math.min(min, limit / sum); | |

return min; | |

} | |

/// Scales all radii so that on each side their sum will not exceed the size | |

/// of the width/height. | |

/// | |

/// Skia already handles RRects with radii that are too large in this way. | |

/// Therefore, this method is only needed for RRect use cases that require | |

/// the appropriately scaled radii values. | |

/// | |

/// See the [Skia scaling implementation](https://github.com/google/skia/blob/master/src/core/SkRRect.cpp) | |

/// for more details. | |

RRect scaleRadii() { | |

double scale = 1.0; | |

scale = _getMin(scale, blRadiusY, tlRadiusY, height); | |

scale = _getMin(scale, tlRadiusX, trRadiusX, width); | |

scale = _getMin(scale, trRadiusY, brRadiusY, height); | |

scale = _getMin(scale, brRadiusX, blRadiusX, width); | |

if (scale < 1.0) { | |

return RRect._raw( | |

top: top, | |

left: left, | |

right: right, | |

bottom: bottom, | |

tlRadiusX: tlRadiusX * scale, | |

tlRadiusY: tlRadiusY * scale, | |

trRadiusX: trRadiusX * scale, | |

trRadiusY: trRadiusY * scale, | |

blRadiusX: blRadiusX * scale, | |

blRadiusY: blRadiusY * scale, | |

brRadiusX: brRadiusX * scale, | |

brRadiusY: brRadiusY * scale, | |

); | |

} | |

return RRect._raw( | |

top: top, | |

left: left, | |

right: right, | |

bottom: bottom, | |

tlRadiusX: tlRadiusX, | |

tlRadiusY: tlRadiusY, | |

trRadiusX: trRadiusX, | |

trRadiusY: trRadiusY, | |

blRadiusX: blRadiusX, | |

blRadiusY: blRadiusY, | |

brRadiusX: brRadiusX, | |

brRadiusY: brRadiusY, | |

); | |

} | |

/// Whether the point specified by the given offset (which is assumed to be | |

/// relative to the origin) lies inside the rounded rectangle. | |

/// | |

/// This method may allocate (and cache) a copy of the object with normalized | |

/// radii the first time it is called on a particular [RRect] instance. When | |

/// using this method, prefer to reuse existing [RRect]s rather than | |

/// recreating the object each time. | |

bool contains(Offset point) { | |

if (point.dx < left || point.dx >= right || point.dy < top || point.dy >= bottom) | |

return false; // outside bounding box | |

final RRect scaled = scaleRadii(); | |

double x; | |

double y; | |

double radiusX; | |

double radiusY; | |

// check whether point is in one of the rounded corner areas | |

// x, y -> translate to ellipse center | |

if (point.dx < left + scaled.tlRadiusX && | |

point.dy < top + scaled.tlRadiusY) { | |

x = point.dx - left - scaled.tlRadiusX; | |

y = point.dy - top - scaled.tlRadiusY; | |

radiusX = scaled.tlRadiusX; | |

radiusY = scaled.tlRadiusY; | |

} else if (point.dx > right - scaled.trRadiusX && | |

point.dy < top + scaled.trRadiusY) { | |

x = point.dx - right + scaled.trRadiusX; | |

y = point.dy - top - scaled.trRadiusY; | |

radiusX = scaled.trRadiusX; | |

radiusY = scaled.trRadiusY; | |

} else if (point.dx > right - scaled.brRadiusX && | |

point.dy > bottom - scaled.brRadiusY) { | |

x = point.dx - right + scaled.brRadiusX; | |

y = point.dy - bottom + scaled.brRadiusY; | |

radiusX = scaled.brRadiusX; | |

radiusY = scaled.brRadiusY; | |

} else if (point.dx < left + scaled.blRadiusX && | |

point.dy > bottom - scaled.blRadiusY) { | |

x = point.dx - left - scaled.blRadiusX; | |

y = point.dy - bottom + scaled.blRadiusY; | |

radiusX = scaled.blRadiusX; | |

radiusY = scaled.blRadiusY; | |

} else { | |

return true; // inside and not within the rounded corner area | |

} | |

x = x / radiusX; | |

y = y / radiusY; | |

// check if the point is outside the unit circle | |

if (x * x + y * y > 1.0) | |

return false; | |

return true; | |

} | |

/// Linearly interpolate between two rounded rectangles. | |

/// | |

/// If either is null, this function substitutes [RRect.zero] instead. | |

/// | |

/// The `t` argument represents position on the timeline, with 0.0 meaning | |

/// that the interpolation has not started, returning `a` (or something | |

/// equivalent to `a`), 1.0 meaning that the interpolation has finished, | |

/// returning `b` (or something equivalent to `b`), and values in between | |

/// meaning that the interpolation is at the relevant point on the timeline | |

/// between `a` and `b`. The interpolation can be extrapolated beyond 0.0 and | |

/// 1.0, so negative values and values greater than 1.0 are valid (and can | |

/// easily be generated by curves such as [Curves.elasticInOut]). | |

/// | |

/// Values for `t` are usually obtained from an [Animation<double>], such as | |

/// an [AnimationController]. | |

static RRect? lerp(RRect? a, RRect? b, double t) { | |

assert(t != null); | |

if (b == null) { | |

if (a == null) { | |

return null; | |

} else { | |

final double k = 1.0 - t; | |

return RRect._raw( | |

left: a.left * k, | |

top: a.top * k, | |

right: a.right * k, | |

bottom: a.bottom * k, | |

tlRadiusX: a.tlRadiusX * k, | |

tlRadiusY: a.tlRadiusY * k, | |

trRadiusX: a.trRadiusX * k, | |

trRadiusY: a.trRadiusY * k, | |

brRadiusX: a.brRadiusX * k, | |

brRadiusY: a.brRadiusY * k, | |

blRadiusX: a.blRadiusX * k, | |

blRadiusY: a.blRadiusY * k, | |

); | |

} | |

} else { | |

if (a == null) { | |

return RRect._raw( | |

left: b.left * t, | |

top: b.top * t, | |

right: b.right * t, | |

bottom: b.bottom * t, | |

tlRadiusX: b.tlRadiusX * t, | |

tlRadiusY: b.tlRadiusY * t, | |

trRadiusX: b.trRadiusX * t, | |

trRadiusY: b.trRadiusY * t, | |

brRadiusX: b.brRadiusX * t, | |

brRadiusY: b.brRadiusY * t, | |

blRadiusX: b.blRadiusX * t, | |

blRadiusY: b.blRadiusY * t, | |

); | |

} else { | |

return RRect._raw( | |

left: _lerpDouble(a.left, b.left, t), | |

top: _lerpDouble(a.top, b.top, t), | |

right: _lerpDouble(a.right, b.right, t), | |

bottom: _lerpDouble(a.bottom, b.bottom, t), | |

tlRadiusX: _lerpDouble(a.tlRadiusX, b.tlRadiusX, t), | |

tlRadiusY: _lerpDouble(a.tlRadiusY, b.tlRadiusY, t), | |

trRadiusX: _lerpDouble(a.trRadiusX, b.trRadiusX, t), | |

trRadiusY: _lerpDouble(a.trRadiusY, b.trRadiusY, t), | |

brRadiusX: _lerpDouble(a.brRadiusX, b.brRadiusX, t), | |

brRadiusY: _lerpDouble(a.brRadiusY, b.brRadiusY, t), | |

blRadiusX: _lerpDouble(a.blRadiusX, b.blRadiusX, t), | |

blRadiusY: _lerpDouble(a.blRadiusY, b.blRadiusY, t), | |

); | |

} | |

} | |

} | |

@override | |

bool operator ==(Object other) { | |

if (identical(this, other)) | |

return true; | |

if (runtimeType != other.runtimeType) | |

return false; | |

return other is RRect | |

&& other.left == left | |

&& other.top == top | |

&& other.right == right | |

&& other.bottom == bottom | |

&& other.tlRadiusX == tlRadiusX | |

&& other.tlRadiusY == tlRadiusY | |

&& other.trRadiusX == trRadiusX | |

&& other.trRadiusY == trRadiusY | |

&& other.blRadiusX == blRadiusX | |

&& other.blRadiusY == blRadiusY | |

&& other.brRadiusX == brRadiusX | |

&& other.brRadiusY == brRadiusY; | |

} | |

@override | |

int get hashCode => hashValues(left, top, right, bottom, | |

tlRadiusX, tlRadiusY, trRadiusX, trRadiusY, | |

blRadiusX, blRadiusY, brRadiusX, brRadiusY); | |

@override | |

String toString() { | |

final String rect = '${left.toStringAsFixed(1)}, ' | |

'${top.toStringAsFixed(1)}, ' | |

'${right.toStringAsFixed(1)}, ' | |

'${bottom.toStringAsFixed(1)}'; | |

if (tlRadius == trRadius && | |

trRadius == brRadius && | |

brRadius == blRadius) { | |

if (tlRadius.x == tlRadius.y) | |

return 'RRect.fromLTRBR($rect, ${tlRadius.x.toStringAsFixed(1)})'; | |

return 'RRect.fromLTRBXY($rect, ${tlRadius.x.toStringAsFixed(1)}, ${tlRadius.y.toStringAsFixed(1)})'; | |

} | |

return 'RRect.fromLTRBAndCorners(' | |

'$rect, ' | |

'topLeft: $tlRadius, ' | |

'topRight: $trRadius, ' | |

'bottomRight: $brRadius, ' | |

'bottomLeft: $blRadius' | |

')'; | |

} | |

} | |

/// A transform consisting of a translation, a rotation, and a uniform scale. | |

/// | |

/// Used by [Canvas.drawAtlas]. This is a more efficient way to represent these | |

/// simple transformations than a full matrix. | |

// Modeled after Skia's SkRSXform. | |

class RSTransform { | |

/// Creates an RSTransform. | |

/// | |

/// An [RSTransform] expresses the combination of a translation, a rotation | |

/// around a particular point, and a scale factor. | |

/// | |

/// The first argument, `scos`, is the cosine of the rotation, multiplied by | |

/// the scale factor. | |

/// | |

/// The second argument, `ssin`, is the sine of the rotation, multiplied by | |

/// that same scale factor. | |

/// | |

/// The third argument is the x coordinate of the translation, minus the | |

/// `scos` argument multiplied by the x-coordinate of the rotation point, plus | |

/// the `ssin` argument multiplied by the y-coordinate of the rotation point. | |

/// | |

/// The fourth argument is the y coordinate of the translation, minus the `ssin` | |

/// argument multiplied by the x-coordinate of the rotation point, minus the | |

/// `scos` argument multiplied by the y-coordinate of the rotation point. | |

/// | |

/// The [RSTransform.fromComponents] method may be a simpler way to | |

/// construct these values. However, if there is a way to factor out the | |

/// computations of the sine and cosine of the rotation so that they can be | |

/// reused over multiple calls to this constructor, it may be more efficient | |

/// to directly use this constructor instead. | |

RSTransform(double scos, double ssin, double tx, double ty) { | |

_value | |

..[0] = scos | |

..[1] = ssin | |

..[2] = tx | |

..[3] = ty; | |

} | |

/// Creates an RSTransform from its individual components. | |

/// | |

/// The `rotation` parameter gives the rotation in radians. | |

/// | |

/// The `scale` parameter describes the uniform scale factor. | |

/// | |

/// The `anchorX` and `anchorY` parameters give the coordinate of the point | |

/// around which to rotate. | |

/// | |

/// The `translateX` and `translateY` parameters give the coordinate of the | |

/// offset by which to translate. | |

/// | |

/// This constructor computes the arguments of the [new RSTransform] | |

/// constructor and then defers to that constructor to actually create the | |

/// object. If many [RSTransform] objects are being created and there is a way | |

/// to factor out the computations of the sine and cosine of the rotation | |

/// (which are computed each time this constructor is called) and reuse them | |

/// over multiple [RSTransform] objects, it may be more efficient to directly | |

/// use the more direct [new RSTransform] constructor instead. | |

factory RSTransform.fromComponents({ | |

required double rotation, | |

required double scale, | |

required double anchorX, | |

required double anchorY, | |

required double translateX, | |

required double translateY | |

}) { | |

final double scos = math.cos(rotation) * scale; | |

final double ssin = math.sin(rotation) * scale; | |

final double tx = translateX + -scos * anchorX + ssin * anchorY; | |

final double ty = translateY + -ssin * anchorX - scos * anchorY; | |

return RSTransform(scos, ssin, tx, ty); | |

} | |

final Float32List _value = Float32List(4); | |

/// The cosine of the rotation multiplied by the scale factor. | |

double get scos => _value[0]; | |

/// The sine of the rotation multiplied by that same scale factor. | |

double get ssin => _value[1]; | |

/// The x coordinate of the translation, minus [scos] multiplied by the | |

/// x-coordinate of the rotation point, plus [ssin] multiplied by the | |

/// y-coordinate of the rotation point. | |

double get tx => _value[2]; | |

/// The y coordinate of the translation, minus [ssin] multiplied by the | |

/// x-coordinate of the rotation point, minus [scos] multiplied by the | |

/// y-coordinate of the rotation point. | |

double get ty => _value[3]; | |

} |