68 lines
2.3 KiB
C#
68 lines
2.3 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Linq;
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using UnityEngine;
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using Random = UnityEngine.Random;
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namespace VOID.Generic.Util
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{
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public static class RandomUtil
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{
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/// <summary>
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/// Reinit random with given seed.
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/// </summary>
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public static void InitState(int seed)
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{
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Random.InitState(seed);
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}
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/// <summary>
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/// Returns random integer between min and max.
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/// </summary>
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public static int RandomInteger(int min = 0, int max = 100)
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{
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return Mathf.RoundToInt(Random.value * (max-min)) + min;
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}
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/// <summary>
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/// Returns random float between min and max.
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/// </summary>
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public static float RandomFloat(float min = 0, float max = 1)
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{
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return Random.value * (max-min) + min;
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}
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/// <summary>
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/// Returns random element from given collection.
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/// </summary>
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public static T RandomElement<T>(IEnumerable<T> enumerable)
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{
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return RandomElements(enumerable, 1)[0];
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}
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/// <summary>
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/// Returns random element from given collection.
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/// </summary>
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public static List<T> RandomElements<T>(IEnumerable<T> enumerable, int count, bool repeatable = false)
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{
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var list = enumerable.ToList();
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// Not repeatable - we can take each value only once - sort by random and get needed amount
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if (!repeatable) return list.OrderBy(_ => RandomFloat()).Take(count).ToList();
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// Repeatable - randomize each time and get value from list
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return new T[count].Select(_ => list[RandomInteger(0, list.Count - 1)]).ToList();
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}
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/// <summary>
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/// Returns random element from given collection by function that determine weight.
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/// </summary>
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public static T RandomElementByWeight<T>(IEnumerable<T> enumerable, Func<T, float> getWeight)
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{
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var list = enumerable.ToList();
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var maxWeight = list.Sum(getWeight.Invoke);
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var randomWeight = RandomFloat(0, maxWeight);
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return list.FirstOrDefault(element => (randomWeight -= getWeight.Invoke(element)) <= 0f);
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}
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}
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} |