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pkg/dev_compiler/tool/input_sdk/lib/math/rectangle.dart

-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-part of dart.math;
-
-/**
- * A base class for representing two-dimensional axis-aligned rectangles.
- *
- * This rectangle uses a left-handed Cartesian coordinate system, with x
- * directed to the right and y directed down, as per the convention in 2D
- * computer graphics.
- *
- * See also:
- *    [W3C Coordinate Systems Specification](http://www.w3.org/TR/SVG/coords.html#InitialCoordinateSystem).
- *
- * The rectangle is the set of points with representable coordinates greater
- * than or equal to left/top, and with distance to left/top no greater than
- * width/height (to the limit of the precission of the coordinates).
- */
-abstract class _RectangleBase<T extends num> {
-  const _RectangleBase();
-
-  /** The x-coordinate of the left edge. */
-  T get left;
-  /** The y-coordinate of the top edge. */
-  T get top;
-  /** The width of the rectangle. */
-  T get width;
-  /** The height of the rectangle. */
-  T get height;
-
-  /** The x-coordinate of the right edge. */
-  T get right => left + width;
-  /** The y-coordinate of the bottom edge. */
-  T get bottom => top + height;
-
-  String toString() {
-    return 'Rectangle ($left, $top) $width x $height';
-  }
-
-  bool operator ==(other) {
-    if (other is !Rectangle) return false;
-    // TODO(rnystrom): Type promotion doesn't currently promote the [other]
-    // to Rectangle from the above line, so do it explicitly here to avoid a
-    // dynamic send and work around:
-    // https://github.com/dart-lang/sdk/issues/27551
-    var otherRect = other as Rectangle;
-    return left == otherRect.left &&
-        top == otherRect.top &&
-        right == otherRect.right &&
-        bottom == otherRect.bottom;
-  }
-
-  int get hashCode => _JenkinsSmiHash.hash4(left.hashCode, top.hashCode,
-      right.hashCode, bottom.hashCode);
-
-  /**
-   * Computes the intersection of `this` and [other].
-   *
-   * The intersection of two axis-aligned rectangles, if any, is always another
-   * axis-aligned rectangle.
-   *
-   * Returns the intersection of this and `other`, or `null` if they don't
-   * intersect.
-   */
-  Rectangle<T> intersection(Rectangle<T> other) {
-    var x0 = max(left, other.left);
-    var x1 = min(left + width, other.left + other.width);
-
-    if (x0 <= x1) {
-      var y0 = max(top, other.top);
-      var y1 = min(top + height, other.top + other.height);
-
-      if (y0 <= y1) {
-        return new Rectangle<T>(x0, y0, x1 - x0, y1 - y0);
-      }
-    }
-    return null;
-  }
-
-
-  /**
-   * Returns true if `this` intersects [other].
-   */
-  bool intersects(Rectangle<num> other) {
-    return (left <= other.left + other.width &&
-        other.left <= left + width &&
-        top <= other.top + other.height &&
-        other.top <= top + height);
-  }
-
-  /**
-   * Returns a new rectangle which completely contains `this` and [other].
-   */
-  Rectangle<T> boundingBox(Rectangle<T> other) {
-    var right = max(this.left + this.width, other.left + other.width);
-    var bottom = max(this.top + this.height, other.top + other.height);
-
-    var left = min(this.left, other.left);
-    var top = min(this.top, other.top);
-
-    return new Rectangle<T>(left, top, right - left, bottom - top);
-  }
-
-  /**
-   * Tests whether `this` entirely contains [another].
-   */
-  bool containsRectangle(Rectangle<num> another) {
-    return left <= another.left &&
-           left + width >= another.left + another.width &&
-           top <= another.top &&
-           top + height >= another.top + another.height;
-  }
-
-  /**
-   * Tests whether [another] is inside or along the edges of `this`.
-   */
-  bool containsPoint(Point<num> another) {
-    return another.x >= left &&
-           another.x <= left + width &&
-           another.y >= top &&
-           another.y <= top + height;
-  }
-
-  Point<T> get topLeft => new Point<T>(this.left, this.top);
-  Point<T> get topRight => new Point<T>(this.left + this.width, this.top);
-  Point<T> get bottomRight => new Point<T>(this.left + this.width,
-      this.top + this.height);
-  Point<T> get bottomLeft => new Point<T>(this.left,
-      this.top + this.height);
-}
-
-
-/**
- * A class for representing two-dimensional rectangles whose properties are
- * immutable.
- */
-class Rectangle<T extends num> extends _RectangleBase<T> {
-  final T left;
-  final T top;
-  final T width;
-  final T height;
-
-  /**
-   * Create a rectangle spanned by `(left, top)` and `(left+width, top+height)`.
-   *
-   * The rectangle contains the points
-   * with x-coordinate between `left` and `left + width`, and
-   * with y-coordinate between `top` and `top + height`, both inclusive.
-   *
-   * The `width` and `height` should be non-negative.
-   * If `width` or `height` are negative, they are clamped to zero.
-   *
-   * If `width` and `height` are zero, the "rectangle" comprises only the single
-   * point `(left, top)`.
-   */
-  const Rectangle(this.left, this.top, T width, T height)
-      : this.width = (width < 0) ? -width * 0 : width,  // Inline _clampToZero.
-        this.height = (height < 0) ?  -height * 0 : height;
-
-  /**
-   * Create a rectangle spanned by the points [a] and [b];
-   *
-   * The rectangle contains the points
-   * with x-coordinate between `a.x` and `b.x`, and
-   * with y-coordinate between `a.y` and `b.y`, both inclusive.
-   *
-   * If the distance between `a.x` and `b.x` is not representable
-   * (which can happen if one or both is a double),
-   * the actual right edge might be slightly off from `max(a.x, b.x)`.
-   * Similar for the y-coordinates and the bottom edge.
-   */
-  factory Rectangle.fromPoints(Point<T> a, Point<T> b) {
-    T left = min(a.x, b.x);
-    T width = max(a.x, b.x) - left;
-    T top = min(a.y, b.y);
-    T height = max(a.y, b.y) - top;
-    return new Rectangle<T>(left, top, width, height);
-  }
-}
-
-/**
- * A class for representing two-dimensional axis-aligned rectangles with mutable
- * properties.
- */
-class MutableRectangle<T extends num> extends _RectangleBase<T>
-                                      implements Rectangle<T> {
-
-  /**
-   * The x-coordinate of the left edge.
-   *
-   * Setting the value will move the rectangle without changing its width.
-   */
-  T left;
-  /**
-   * The y-coordinate of the left edge.
-   *
-   * Setting the value will move the rectangle without changing its height.
-   */
-  T top;
-  T _width;
-  T _height;
-
-  /**
-   * Create a mutable rectangle spanned by `(left, top)` and
-   * `(left+width, top+height)`.
-   *
-   * The rectangle contains the points
-   * with x-coordinate between `left` and `left + width`, and
-   * with y-coordinate between `top` and `top + height`, both inclusive.
-   *
-   * The `width` and `height` should be non-negative.
-   * If `width` or `height` are negative, they are clamped to zero.
-   *
-   * If `width` and `height` are zero, the "rectangle" comprises only the single
-   * point `(left, top)`.
-   */
-  MutableRectangle(this.left, this.top, T width, T height)
-      : this._width = (width < 0) ? _clampToZero/*<T>*/(width) : width,
-        this._height = (height < 0) ? _clampToZero/*<T>*/(height) : height;
-
-  /**
-   * Create a mutable rectangle spanned by the points [a] and [b];
-   *
-   * The rectangle contains the points
-   * with x-coordinate between `a.x` and `b.x`, and
-   * with y-coordinate between `a.y` and `b.y`, both inclusive.
-   *
-   * If the distance between `a.x` and `b.x` is not representable
-   * (which can happen if one or both is a double),
-   * the actual right edge might be slightly off from `max(a.x, b.x)`.
-   * Similar for the y-coordinates and the bottom edge.
-   */
-  factory MutableRectangle.fromPoints(Point<T> a, Point<T> b) {
-    T left = min(a.x, b.x);
-    T width = max(a.x, b.x) - left;
-    T top = min(a.y, b.y);
-    T height = max(a.y, b.y) - top;
-    return new MutableRectangle<T>(left, top, width, height);
-  }
-
-  T get width => _width;
-
- /**
-   * Sets the width of the rectangle.
-   *
-   * The width must be non-negative.
-   * If a negative width is supplied, it is clamped to zero.
-   *
-   * Setting the value will change the right edge of the rectangle,
-   * but will not change [left].
-   */
-  void set width(T width) {
-    if (width < 0) width = _clampToZero/*<T>*/(width);
-    _width = width;
-  }
-
-  T get height => _height;
-
-  /**
-   * Sets the height of the rectangle.
-   *
-   * The height must be non-negative.
-   * If a negative height is supplied, it is clamped to zero.
-   *
-   * Setting the value will change the bottom edge of the rectangle,
-   * but will not change [top].
-   */
-  void set height(T height) {
-    if (height < 0) height = _clampToZero/*<T>*/(height);
-    _height = height;
-  }
-}
-
-/**
- * Converts a negative [int] or [double] to a zero-value of the same type.
- *
- * Returns `0` if value is int, `0.0` if value is double.
- */
-num/*=T*/ _clampToZero/*<T extends num>*/(num/*=T*/ value) {
-  assert(value < 0);
-  return -value * 0;
-}