1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
|
/*-------------------------------------------------------------------------
* drawElements Quality Program OpenGL ES Utilities
* ------------------------------------------------
*
* Copyright 2014 The Android Open Source Project
*
* 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.
*
*/
/**
* This class allows one to create a random integer, floating point number or boolean (TODO, deRandom.choose random items from a list and deRandom.shuffle an array)
*/
'use strict';
goog.provide('framework.delibs.debase.deRandom');
goog.scope(function() {
var deRandom = framework.delibs.debase.deRandom;
/**
* Array of pseudo random numbers based on seed
* @constructor
* @struct
*/
deRandom.deRandom = function() {
/** @type {number} */ this.x = 0;
/** @type {number} */ this.y = 0;
/** @type {number} */ this.z = 0;
/** @type {number} */ this.w = 0;
};
/**
* deRandom.Random number generator init
* @param {deRandom.deRandom} rnd Array to store random numbers
* @param {number} seed Number for seed
*/
deRandom.deRandom_init = function(rnd, seed) {
rnd.x = (-seed ^ 123456789);
rnd.y = (362436069 * seed);
rnd.z = (521288629 ^ (seed >> 7));
rnd.w = (88675123 ^ (seed << 3));
};
/**
* Function to get random int
* @param {deRandom.deRandom} rnd Initialised array of random numbers
* @param {Array<number>=} opts Min and max for range
* @return {number} deRandom.Random int
*/
deRandom.deRandom_getInt = function(rnd, opts) {
if (opts != undefined && opts[0] != undefined && opts[1] != undefined) {
if (opts[0] == 0x80000000 && opts[1] == 0x7fffffff) {
return deRandom.deRandom_getInt(rnd);
} else {
return opts[0] + (deRandom.deRandom_getInt(rnd) % (opts[1] - opts[0] + 1));
}
}
var w = rnd.w;
var t;
t = rnd.x ^ (rnd.x << 11);
rnd.x = rnd.y;
rnd.y = rnd.z;
rnd.z = w;
rnd.w = w = (w ^ (w >> 19)) ^ (t ^ (t >> 8));
return w;
};
/**
* Function to get random float
* @param {deRandom.deRandom} rnd Initialised array of random numbers
* @param {Array<number>=} opts Min and max for range
* @return {number} deRandom.Random float
*/
deRandom.deRandom_getFloat = function(rnd, opts) {
if (opts != undefined && opts[0] != undefined && opts[1] != undefined) {
if (opts[0] <= opts[1]) {
return opts[0] + (opts[1] - opts[0]) * deRandom.deRandom_getFloat(rnd);
}
} else {
return (deRandom.deRandom_getInt(rnd) & 0xFFFFFFF) / (0xFFFFFFF + 1);
}
throw new Error('Invalid arguments');
};
/**
* Function to get random boolean
* @param {deRandom.deRandom} rnd Initialised array of random numbers
* @return {boolean} deRandom.Random boolean
*/
deRandom.deRandom_getBool = function(rnd) {
var val;
val = deRandom.deRandom_getInt(rnd);
return ((val & 0xFFFFFF) < 0x800000);
};
/**
* Function to get a common base seed
* @return {number} constant
*/
deRandom.getBaseSeed = function() {
return 42;
};
/**
* TODO Function to deRandom.choose random items from a list
* @template T
* @param {deRandom.deRandom} rnd Initialised array of random numbers
* @param {Array<T>} elements Array segment already defined
* @param {Array<T>=} resultOut Array where to store the elements in. If undefined, default to array of (num) elements.
* @param {number=} num Number of items to store in resultOut. If undefined, default to 1.
* @return {Array<T>} Even though result is stored in resultOut, return it here as well.
*/
deRandom.choose = function(rnd, elements, resultOut, num) {
var items = num || 1;
var temp = elements.slice();
if (!resultOut)
resultOut = [];
while (items-- > 0) {
var index = deRandom.deRandom_getInt(rnd, [0, temp.length - 1]);
resultOut.push(temp[index]);
temp.splice(index, 1);
}
return resultOut;
};
/**
* TODO Function to deRandom.choose weighted random items from a list
* @param {deRandom.deRandom} rnd Initialised randomizer
* @param {Array<number>} array Array to choose items from
* @param {Array<number>} weights Weights array
* @return {number} Result output
*/
deRandom.chooseWeighted = function(rnd, array, weights) {
// Compute weight sum
/** @type {number} */ var weightSum = 0.0;
/** @type {number} */ var ndx;
for (ndx = 0; ndx < array.length; ndx++)
weightSum += weights[ndx];
// Random point in 0..weightSum
/** @type {number} */ var p = deRandom.deRandom_getFloat(rnd, [0.0, weightSum]);
// Find item in range
/** @type {number} */ var lastNonZero = array.length;
/** @type {number} */ var curWeight = 0.0;
for (ndx = 0; ndx != array.length; ndx++) {
/** @type {number} */ var w = weights[ndx];
curWeight += w;
if (p < curWeight)
return array[ndx];
else if (w > 0.0)
lastNonZero = ndx;
}
assertMsgOptions(lastNonZero != array.length, 'Index went out of bounds', false, true);
return array[lastNonZero];
};
/**
* TODO Function to deRandom.shuffle an array
* @param {deRandom.deRandom} rnd Initialised array of random numbers
* @param {Array} elements Array to deRandom.shuffle
* @return {Array} Shuffled array
*/
deRandom.shuffle = function(rnd, elements) {
var index = elements.length;
while (index > 0) {
var random = deRandom.deRandom_getInt(rnd, [0, index - 1]);
index -= 1;
var elem = elements[index];
elements[index] = elements[random];
elements[random] = elem;
}
return elements;
};
/**
* This function is used to create the deRandom.Random object and
* initialise the random number with a seed.
* It contains functions for generating random numbers in a variety of formats
* @constructor
* @param {number} seed Number to use as a seed
*/
deRandom.Random = function(seed) {
/**
* Instance of array of pseudo random numbers based on seeds
*/
this.m_rnd = new deRandom.deRandom();
//initialise the random numbers based on seed
deRandom.deRandom_init(this.m_rnd, seed);
};
/**
* Function to get random boolean
* @return {boolean} deRandom.Random boolean
*/
deRandom.Random.prototype.getBool = function() { return deRandom.deRandom_getBool(this.m_rnd) == true; };
/**
* Function to get random float
* @param {number=} min Min for range
* @param {number=} max Max for range
* @return {number} deRandom.Random float
*/
deRandom.Random.prototype.getFloat = function(min, max) { return deRandom.deRandom_getFloat(this.m_rnd, [min, max]) };
/**
* Function to get random int
* @param {number=} min Min for range
* @param {number=} max Max for range
* @return {number} deRandom.Random int
*/
deRandom.Random.prototype.getInt = function(min, max) {return deRandom.deRandom_getInt(this.m_rnd, [min, max])};
/**
* TODO Function to deRandom.choose random items from a list
* @template T
* @param {Array<T>} elements Array segment already defined
* @param {Array<T>=} resultOut Array where to store the elements in. If undefined, default to array of (num) elements.
* @param {number=} num Number of items to store in resultOut. If undefined, default to 1.
* @return {Array<T>} Even though result is stored in resultOut, return it here as well.
*/
deRandom.Random.prototype.choose = function(elements, resultOut, num) {return deRandom.choose(this.m_rnd, elements, resultOut, num)};
/**
* choose weighted random items from a list
* @param {Array<number>} array Array to choose items from
* @param {Array<number>} weights Weights array
* @return {number} Result output
*/
deRandom.Random.prototype.chooseWeighted = function(array, weights) {return deRandom.chooseWeighted(this.m_rnd, array, weights)};
/**
* TODO Function to deRandom.shuffle an array
* @param {Array} elements Array to deRandom.shuffle
* @return {Array} Shuffled array
*/
deRandom.Random.prototype.shuffle = function(elements) {return deRandom.shuffle(this.m_rnd, elements)};
/**
* Function to get a common base seed
* @return {number} constant
*/
deRandom.Random.prototype.getBaseSeed = function() {
return deRandom.getBaseSeed();
};
});
|
