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js/goog/math/size.js

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+/**
+ * @license
+ * Copyright The Closure Library Authors.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview A utility class for representing two-dimensional sizes.
+ */
+
+
+goog.provide('goog.math.Size');
+
+
+
+/**
+ * Class for representing sizes consisting of a width and height. Undefined
+ * width and height support is deprecated and results in compiler warning.
+ * @param {number} width Width.
+ * @param {number} height Height.
+ * @struct
+ * @constructor
+ */
+goog.math.Size = function(width, height) {
+  'use strict';
+  /**
+   * Width
+   * @type {number}
+   */
+  this.width = width;
+
+  /**
+   * Height
+   * @type {number}
+   */
+  this.height = height;
+};
+
+
+/**
+ * Compares sizes for equality.
+ * @param {goog.math.Size} a A Size.
+ * @param {goog.math.Size} b A Size.
+ * @return {boolean} True iff the sizes have equal widths and equal
+ *     heights, or if both are null.
+ */
+goog.math.Size.equals = function(a, b) {
+  'use strict';
+  if (a == b) {
+    return true;
+  }
+  if (!a || !b) {
+    return false;
+  }
+  return a.width == b.width && a.height == b.height;
+};
+
+
+/**
+ * @return {!goog.math.Size} A new copy of the Size.
+ */
+goog.math.Size.prototype.clone = function() {
+  'use strict';
+  return new goog.math.Size(this.width, this.height);
+};
+
+
+if (goog.DEBUG) {
+  /**
+   * Returns a nice string representing size.
+   * @return {string} In the form (50 x 73).
+   * @override
+   */
+  goog.math.Size.prototype.toString = function() {
+    'use strict';
+    return '(' + this.width + ' x ' + this.height + ')';
+  };
+}
+
+
+/**
+ * @return {number} The longer of the two dimensions in the size.
+ */
+goog.math.Size.prototype.getLongest = function() {
+  'use strict';
+  return Math.max(this.width, this.height);
+};
+
+
+/**
+ * @return {number} The shorter of the two dimensions in the size.
+ */
+goog.math.Size.prototype.getShortest = function() {
+  'use strict';
+  return Math.min(this.width, this.height);
+};
+
+
+/**
+ * @return {number} The area of the size (width * height).
+ */
+goog.math.Size.prototype.area = function() {
+  'use strict';
+  return this.width * this.height;
+};
+
+
+/**
+ * @return {number} The perimeter of the size (width + height) * 2.
+ */
+goog.math.Size.prototype.perimeter = function() {
+  'use strict';
+  return (this.width + this.height) * 2;
+};
+
+
+/**
+ * @return {number} The ratio of the size's width to its height.
+ */
+goog.math.Size.prototype.aspectRatio = function() {
+  'use strict';
+  return this.width / this.height;
+};
+
+
+/**
+ * @return {boolean} True if the size has zero area, false if both dimensions
+ *     are non-zero numbers.
+ */
+goog.math.Size.prototype.isEmpty = function() {
+  'use strict';
+  return !this.area();
+};
+
+
+/**
+ * Clamps the width and height parameters upward to integer values.
+ * @return {!goog.math.Size} This size with ceil'd components.
+ */
+goog.math.Size.prototype.ceil = function() {
+  'use strict';
+  this.width = Math.ceil(this.width);
+  this.height = Math.ceil(this.height);
+  return this;
+};
+
+
+/**
+ * @param {!goog.math.Size} target The target size.
+ * @return {boolean} True if this Size is the same size or smaller than the
+ *     target size in both dimensions.
+ */
+goog.math.Size.prototype.fitsInside = function(target) {
+  'use strict';
+  return this.width <= target.width && this.height <= target.height;
+};
+
+
+/**
+ * Clamps the width and height parameters downward to integer values.
+ * @return {!goog.math.Size} This size with floored components.
+ */
+goog.math.Size.prototype.floor = function() {
+  'use strict';
+  this.width = Math.floor(this.width);
+  this.height = Math.floor(this.height);
+  return this;
+};
+
+
+/**
+ * Rounds the width and height parameters to integer values.
+ * @return {!goog.math.Size} This size with rounded components.
+ */
+goog.math.Size.prototype.round = function() {
+  'use strict';
+  this.width = Math.round(this.width);
+  this.height = Math.round(this.height);
+  return this;
+};
+
+
+/**
+ * Scales this size by the given scale factors. The width and height are scaled
+ * by `sx` and `opt_sy` respectively.  If `opt_sy` is not
+ * given, then `sx` is used for both the width and height.
+ * @param {number} sx The scale factor to use for the width.
+ * @param {number=} opt_sy The scale factor to use for the height.
+ * @return {!goog.math.Size} This Size object after scaling.
+ */
+goog.math.Size.prototype.scale = function(sx, opt_sy) {
+  'use strict';
+  const sy = (typeof opt_sy === 'number') ? opt_sy : sx;
+  this.width *= sx;
+  this.height *= sy;
+  return this;
+};
+
+
+/**
+ * Uniformly scales the size to perfectly cover the dimensions of a given size.
+ * If the size is already larger than the target, it will be scaled down to the
+ * minimum size at which it still covers the entire target. The original aspect
+ * ratio will be preserved.
+ *
+ * This function assumes that both Sizes contain strictly positive dimensions.
+ * @param {!goog.math.Size} target The target size.
+ * @return {!goog.math.Size} This Size object, after optional scaling.
+ */
+goog.math.Size.prototype.scaleToCover = function(target) {
+  'use strict';
+  const s = this.aspectRatio() <= target.aspectRatio() ?
+      target.width / this.width :
+      target.height / this.height;
+
+  return this.scale(s);
+};
+
+
+/**
+ * Uniformly scales the size to fit inside the dimensions of a given size. The
+ * original aspect ratio will be preserved.
+ *
+ * This function assumes that both Sizes contain strictly positive dimensions.
+ * @param {!goog.math.Size} target The target size.
+ * @return {!goog.math.Size} This Size object, after optional scaling.
+ */
+goog.math.Size.prototype.scaleToFit = function(target) {
+  'use strict';
+  const s = this.aspectRatio() > target.aspectRatio() ?
+      target.width / this.width :
+      target.height / this.height;
+
+  return this.scale(s);
+};