| // Copyright 2012 The Closure Library Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS-IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| /** |
| * @fileoverview A one dimensional linear interpolator. |
| * |
| */ |
| |
| goog.provide('goog.math.interpolator.Linear1'); |
| |
| goog.require('goog.array'); |
| goog.require('goog.asserts'); |
| goog.require('goog.math'); |
| goog.require('goog.math.interpolator.Interpolator1'); |
| |
| |
| |
| /** |
| * A one dimensional linear interpolator. |
| * @implements {goog.math.interpolator.Interpolator1} |
| * @constructor |
| * @final |
| */ |
| goog.math.interpolator.Linear1 = function() { |
| /** |
| * The abscissa of the data points. |
| * @type {!Array<number>} |
| * @private |
| */ |
| this.x_ = []; |
| |
| /** |
| * The ordinate of the data points. |
| * @type {!Array<number>} |
| * @private |
| */ |
| this.y_ = []; |
| }; |
| |
| |
| /** @override */ |
| goog.math.interpolator.Linear1.prototype.setData = function(x, y) { |
| goog.asserts.assert(x.length == y.length, |
| 'input arrays to setData should have the same length'); |
| if (x.length == 1) { |
| this.x_ = [x[0], x[0] + 1]; |
| this.y_ = [y[0], y[0]]; |
| } else { |
| this.x_ = x.slice(); |
| this.y_ = y.slice(); |
| } |
| }; |
| |
| |
| /** @override */ |
| goog.math.interpolator.Linear1.prototype.interpolate = function(x) { |
| var pos = goog.array.binarySearch(this.x_, x); |
| if (pos < 0) { |
| pos = -pos - 2; |
| } |
| pos = goog.math.clamp(pos, 0, this.x_.length - 2); |
| |
| var progress = (x - this.x_[pos]) / (this.x_[pos + 1] - this.x_[pos]); |
| return goog.math.lerp(this.y_[pos], this.y_[pos + 1], progress); |
| }; |
| |
| |
| /** @override */ |
| goog.math.interpolator.Linear1.prototype.getInverse = function() { |
| var interpolator = new goog.math.interpolator.Linear1(); |
| interpolator.setData(this.y_, this.x_); |
| return interpolator; |
| }; |