@zxing/library
Version:
TypeScript port of ZXing multi-format 1D/2D barcode image processing library.
78 lines (77 loc) • 2.89 kB
JavaScript
/*
* Copyright 2012 ZXing authors
*
* 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.
*/
/*namespace com.google.zxing.common.detector {*/
/**
* General math-related and numeric utility functions.
*/
export default class MathUtils {
constructor() { }
/**
* Ends up being a bit faster than {@link Math#round(float)}. This merely rounds its
* argument to the nearest int, where x.5 rounds up to x+1. Semantics of this shortcut
* differ slightly from {@link Math#round(float)} in that half rounds down for negative
* values. -2.5 rounds to -3, not -2. For purposes here it makes no difference.
*
* @param d real value to round
* @return nearest {@code int}
*/
static round(d /*float*/) {
if (isNaN(d))
return 0;
if (d <= Number.MIN_SAFE_INTEGER)
return Number.MIN_SAFE_INTEGER;
if (d >= Number.MAX_SAFE_INTEGER)
return Number.MAX_SAFE_INTEGER;
return /*(int) */ (d + (d < 0.0 ? -0.5 : 0.5)) | 0;
}
// TYPESCRIPTPORT: maybe remove round method and call directly Math.round, it looks like it doesn't make sense for js
/**
* @param aX point A x coordinate
* @param aY point A y coordinate
* @param bX point B x coordinate
* @param bY point B y coordinate
* @return Euclidean distance between points A and B
*/
static distance(aX /*float|int*/, aY /*float|int*/, bX /*float|int*/, bY /*float|int*/) {
const xDiff = aX - bX;
const yDiff = aY - bY;
return /*(float) */ Math.sqrt(xDiff * xDiff + yDiff * yDiff);
}
/**
* @param aX point A x coordinate
* @param aY point A y coordinate
* @param bX point B x coordinate
* @param bY point B y coordinate
* @return Euclidean distance between points A and B
*/
// public static distance(aX: number /*int*/, aY: number /*int*/, bX: number /*int*/, bY: number /*int*/): float {
// const xDiff = aX - bX
// const yDiff = aY - bY
// return (float) Math.sqrt(xDiff * xDiff + yDiff * yDiff);
// }
/**
* @param array values to sum
* @return sum of values in array
*/
static sum(array) {
let count = 0;
for (let i = 0, length = array.length; i !== length; i++) {
const a = array[i];
count += a;
}
return count;
}
}