mirror of
https://github.com/Ellpeck/MLEM.git
synced 2024-05-15 13:48:46 +02:00
moved SeedSource to its own file and added Rotate
This commit is contained in:
parent
e3b41ebeea
commit
943616e21a
104
MLEM/Misc/SeedSource.cs
Normal file
104
MLEM/Misc/SeedSource.cs
Normal file
|
|
@ -0,0 +1,104 @@
|
|||
using System;
|
||||
|
||||
namespace MLEM.Misc {
|
||||
/// <summary>
|
||||
/// A seed source contains an <see cref="int"/> value which can be used as a seed for a <see cref="System.Random"/> or <see cref="SingleRandom"/>. Seed sources feature a convenient way to add multiple seeds using <see cref="Add(int)"/>, which will be sufficiently scrambled to be deterministically pseudorandom and combined into a single <see cref="int"/>.
|
||||
/// This struct behaves similarly to <c>System.HashCode</c> in many ways, with an important distinction being that <see cref="SeedSource"/>'s scrambling procedure is not considered an implementation detail, and will stay consistent between process executions.
|
||||
/// </summary>
|
||||
/// <example>
|
||||
/// For example, a seed source can be used to create a new <see cref="System.Random"/> based on an object's <c>x</c> and <c>y</c> coordinates by combining them into a <see cref="SeedSource"/> using <see cref="Add(int)"/>. The values generated by the <see cref="System.Random"/> created using <see cref="Random()"/> will then be determined by the specific pair of <c>x</c> and <c>y</c> values used.
|
||||
/// </example>
|
||||
public readonly struct SeedSource {
|
||||
|
||||
private readonly int? value;
|
||||
|
||||
/// <summary>
|
||||
/// Creates a new seed source from the given seed, which will be added automatically using <see cref="Add(int)"/>.
|
||||
/// </summary>
|
||||
/// <param name="seed">The initial seed to use.</param>
|
||||
public SeedSource(int seed) : this() {
|
||||
this = this.Add(seed);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Creates a new seed source from the given set of seeds, which will be added automatically using <see cref="Add(int)"/>.
|
||||
/// </summary>
|
||||
/// <param name="seeds">The initial seeds to use.</param>
|
||||
public SeedSource(params int[] seeds) : this() {
|
||||
foreach (var seed in seeds)
|
||||
this = this.Add(seed);
|
||||
}
|
||||
|
||||
private SeedSource(int? value) {
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// The algorithm used for adding involves various scrambling operations that sufficiently pseudo-randomize the seed and final value.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(int seed) {
|
||||
return new SeedSource(new int?(SeedSource.Scramble(this.Get()) + SeedSource.Scramble(seed)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// Floating point values are scrambled by invoking <see cref="Add(int)"/> using a typecast version, followed by invoking <see cref="Add(int)"/> using the decimal value multiplied by <see cref="int.MaxValue"/>.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(float seed) {
|
||||
return this.Add((int) seed).Add((seed - (int) seed) * int.MaxValue);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// Strings are scrambled by invoking <see cref="Add(int)"/> using every character contained in the string, in order.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(string seed) {
|
||||
var ret = this;
|
||||
foreach (var c in seed)
|
||||
ret = ret.Add(c);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns a new seed source whose value is this seed source's value, but scrambled further.
|
||||
/// In essence, this creates a new seed source whose value is determined by the current seed source.
|
||||
/// </summary>
|
||||
/// <returns>A new seed source with a rotated value.</returns>
|
||||
public SeedSource Rotate() {
|
||||
return new SeedSource(new int?(SeedSource.Scramble(this.Get())));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns this seed source's seed value, which can then be used in <see cref="SingleRandom"/> or elsewhere.
|
||||
/// </summary>
|
||||
/// <returns>This seed source's value.</returns>
|
||||
public int Get() {
|
||||
return this.value ?? 1623487;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns a new <see cref="Random"/> instance using this source seed's value, retrieved using <see cref="Get"/>.
|
||||
/// </summary>
|
||||
/// <returns>A new <see cref="Random"/> using this seed source's value.</returns>
|
||||
public Random Random() {
|
||||
return new Random(this.Get());
|
||||
}
|
||||
|
||||
private static int Scramble(int x) {
|
||||
x += 84317;
|
||||
x ^= x << 7;
|
||||
x *= 207398809;
|
||||
x ^= x << 17;
|
||||
x *= 928511849;
|
||||
return x;
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
|
|
@ -1,6 +1,4 @@
|
|||
using System;
|
||||
|
||||
namespace MLEM.Misc {
|
||||
namespace MLEM.Misc {
|
||||
/// <summary>
|
||||
/// The SingleRandom class allows generating single, one-off pseudorandom numbers based on a seed or a <see cref="SeedSource"/>.
|
||||
/// The types of numbers that can be generated are <see cref="int"/> and <see cref="float"/>, both of which can be generated with specific minimum and maximum values if desired.
|
||||
|
|
@ -141,96 +139,4 @@ namespace MLEM.Misc {
|
|||
}
|
||||
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// A seed source contains an <see cref="int"/> value which can be used as a seed for a <see cref="System.Random"/> or <see cref="SingleRandom"/>. Seed sources feature a convenient way to add multiple seeds using <see cref="Add(int)"/>, which will be sufficiently scrambled to be deterministically semi-random and combined into a single <see cref="int"/>.
|
||||
/// This struct behaves similarly to <c>System.HashCode</c> in many ways, with an important distinction being that <see cref="SeedSource"/>'s scrambling procedure is not considered an implementation detail, and will stay consistent between process executions.
|
||||
/// </summary>
|
||||
/// <example>
|
||||
/// For example, a seed source can be used to create a new <see cref="System.Random"/> based on an object's <c>x</c> and <c>y</c> coordinates by combining them into a <see cref="SeedSource"/> using <see cref="Add(int)"/>. The values generated by the <see cref="System.Random"/> created using <see cref="Random()"/> will then be determined by the specific pair of <c>x</c> and <c>y</c> values used.
|
||||
/// </example>
|
||||
public readonly struct SeedSource {
|
||||
|
||||
private readonly int? value;
|
||||
|
||||
/// <summary>
|
||||
/// Creates a new seed source from the given seed, which will be added automatically using <see cref="Add(int)"/>.
|
||||
/// </summary>
|
||||
/// <param name="seed">The initial seed to use.</param>
|
||||
public SeedSource(int seed) : this() {
|
||||
this = this.Add(seed);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Creates a new seed source from the given set of seeds, which will be added automatically using <see cref="Add(int)"/>.
|
||||
/// </summary>
|
||||
/// <param name="seeds">The initial seeds to use.</param>
|
||||
public SeedSource(params int[] seeds) : this() {
|
||||
foreach (var seed in seeds)
|
||||
this = this.Add(seed);
|
||||
}
|
||||
|
||||
private SeedSource(int? value) {
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// The algorithm used for adding involves various scrambling operations that sufficiently semi-randomize the seed and final value.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(int seed) {
|
||||
return new SeedSource(new int?(SeedSource.Scramble(this.Get()) + SeedSource.Scramble(seed)));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// Floating point values are scrambled by invoking <see cref="Add(int)"/> using a typecast version, followed by invoking <see cref="Add(int)"/> using the decimal value multiplied by <see cref="int.MaxValue"/>.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(float seed) {
|
||||
return this.Add((int) seed).Add((seed - (int) seed) * int.MaxValue);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Adds the given seed to this seed source's value and returns the result as a new seed source.
|
||||
/// Strings are scrambled by invoking <see cref="Add(int)"/> using every character contained in the string, in order.
|
||||
/// </summary>
|
||||
/// <param name="seed">The seed to add.</param>
|
||||
/// <returns>A new seed source with the seed added.</returns>
|
||||
public SeedSource Add(string seed) {
|
||||
var ret = this;
|
||||
foreach (var c in seed)
|
||||
ret = ret.Add(c);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns this seed source's seed value, which can then be used in <see cref="SingleRandom"/> or elsewhere.
|
||||
/// </summary>
|
||||
/// <returns>This seed source's value.</returns>
|
||||
public int Get() {
|
||||
return this.value ?? 1623487;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns a new <see cref="Random"/> instance using this source seed's value, retrieved using <see cref="Get"/>.
|
||||
/// </summary>
|
||||
/// <returns>A new <see cref="Random"/> using this seed source's value.</returns>
|
||||
public Random Random() {
|
||||
return new Random(this.Get());
|
||||
}
|
||||
|
||||
private static int Scramble(int x) {
|
||||
x += 84317;
|
||||
x ^= x << 7;
|
||||
x *= 207398809;
|
||||
x ^= x << 17;
|
||||
x *= 928511849;
|
||||
return x;
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue