Mirrors/phaser
2
0
Fork 0
mirror of https://github.com/photonstorm/phaser synced 2024-11-28 07:31:11 +00:00
Code Issues Projects Releases Packages Wiki Activity

ArrayUtils - minor corrections

Browse source 
- Corrected off-by-one issue; the effect is the same but it is arguably
  more correct.

- Fixed getRandomItem; it would previously return null for false'y values
  (false/''/0) which was against the defined contract.

- Updated documentation / documented types
This commit is contained in:
Paul 2014-12-01 23:06:06 -08:00
parent 152b26a668
commit bdacef8170
1 changed files with 20 additions and 14 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

34
src/utils/ArrayUtils.js
View file

@ -14,7 +14,9 @@ Phaser.ArrayUtils = {
/** /**
* Fetch a random entry from the given array. * Fetch a random entry from the given array.
* Will return null if random selection is missing, or array has no entries. *
* Will return null if there are no array items that fall within the specified range
* or if there is no item for the randomly choosen index.
* *
* @method * @method
* @param {any[]} objects - An array of objects. * @param {any[]} objects - An array of objects.
@ -32,7 +34,7 @@ Phaser.ArrayUtils = {
if (typeof length === 'undefined') { length = objects.length; } if (typeof length === 'undefined') { length = objects.length; }
var randomIndex = startIndex + Math.floor(Math.random() * length); var randomIndex = startIndex + Math.floor(Math.random() * length);
return objects[randomIndex] || null; return objects[randomIndex] === undefined ? null : objects[randomIndex];
}, },
@ -90,21 +92,24 @@ Phaser.ArrayUtils = {
}, },
/** /**
* Transposes the elements of the given Array. * Transposes the elements of the given matrix (array of arrays).
* *
* @method * @method
* @param {array[]} array - The array to transpose. * @param {Array<any[]>} array - The matrix to transpose.
* @return {array[]} The transposed array. * @return {Array<any[]>} A new transposed matrix
*/ */
transposeMatrix: function (array) { transposeMatrix: function (array) {
var result = new Array(array[0].length); var sourceRowCount = array.length;
var sourceColCount = array[0].length;
for (var i = 0; i < array[0].length; i++) var result = new Array(sourceColCount);
for (var i = 0; i < sourceColCount; i++)
{ {
result[i] = new Array(array.length - 1); result[i] = new Array(sourceRowCount);
for (var j = array.length - 1; j > -1; j--) for (var j = sourceRowCount - 1; j > -1; j--)
{ {
result[i][j] = array[j][i]; result[i][j] = array[j][i];
} }
@ -115,13 +120,14 @@ Phaser.ArrayUtils = {
}, },
/** /**
* Rotates the given array. * Rotates the given matrix (array of arrays).
* Based on the routine from http://jsfiddle.net/MrPolywhirl/NH42z/ *
* Based on the routine from {@link http://jsfiddle.net/MrPolywhirl/NH42z/}.
* *
* @method * @method
* @param {array[]} matrix - The array to rotate. * @param {Array<any[]>} matrix - The array to rotate; this matrix _may_ be altered.
* @param {number|string} direction - The amount to rotate. Either a number: 90, -90, 270, -270, 180 or a string: 'rotateLeft', 'rotateRight' or 'rotate180' * @param {number|string} direction - The amount to rotate: the roation in degrees (90, -90, 270, -270, 180) or a string command ('rotateLeft', 'rotateRight' or 'rotate180').
* @return {array[]} The rotated array * @return {Array<any[]>} The rotated matrix. The source matrix should be discarded for the returned matrix.
*/ */
rotateMatrix: function (matrix, direction) { rotateMatrix: function (matrix, direction) {