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pkg/dev_compiler/tool/input_sdk/lib/math/point.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 utility class for representing two-dimensional positions.
- */
-class Point<T extends num> {
-  final T x;
-  final T y;
-
-  const Point(T x, T y): this.x = x, this.y = y;
-
-  String toString() => 'Point($x, $y)';
-
-  /**
-   * A `Point` is only equal to another `Point` with the same coordinates.
-   *
-   * This point is equal to `other` if, and only if,
-   * `other` is a `Point` with
-   * [x] equal to `other.x` and [y] equal to `other.y`.
-   */
-  bool operator ==(other) {
-    if (other is !Point) return false;
-    return x == other.x && y == other.y;
-  }
-
-  int get hashCode => _JenkinsSmiHash.hash2(x.hashCode, y.hashCode);
-
-  /**
-   * Add [other] to `this`, as if both points were vectors.
-   *
-   * Returns the resulting "vector" as a Point.
-   */
-  Point<T> operator +(Point<T> other) {
-    return new Point<T>(x + other.x, y + other.y);
-  }
-
-  /**
-   * Subtract [other] from `this`, as if both points were vectors.
-   *
-   * Returns the resulting "vector" as a Point.
-   */
-  Point<T> operator -(Point<T> other) {
-    return new Point<T>(x - other.x, y - other.y);
-  }
-
-  /**
-   * Scale this point by [factor] as if it were a vector.
-   *
-   * *Important* *Note*: This function accepts a `num` as its argument only so
-   * that you can scale Point<double> objects by an `int` factor. Because the
-   * star operator always returns the same type of Point that originally called
-   * it, passing in a double [factor] on a `Point<int>` _causes_ _a_
-   * _runtime_ _error_ in checked mode.
-   */
-  Point<T> operator *(num/*T|int*/ factor) {
-    return new Point<T>(
-        (x * factor) as dynamic/*=T*/, (y * factor) as dynamic/*=T*/);
-  }
-
-  /**
-   * Get the straight line (Euclidean) distance between the origin (0, 0) and
-   * this point.
-   */
-  double get magnitude => sqrt(x * x + y * y);
-
-  /**
-   * Returns the distance between `this` and [other].
-   */
-  double distanceTo(Point<T> other) {
-    var dx = x - other.x;
-    var dy = y - other.y;
-    return sqrt(dx * dx + dy * dy);
-  }
-
-  /**
-   * Returns the squared distance between `this` and [other].
-   *
-   * Squared distances can be used for comparisons when the actual value is not
-   * required.
-   */
-  T squaredDistanceTo(Point<T> other) {
-    var dx = x - other.x;
-    var dy = y - other.y;
-    return dx * dx + dy * dy;
-  }
-}