PKHeX/PKHeX.Core/Legality/RNG/Overworld8aRNG.cs
Kurt ff2e890e69 Revise Overworld8a application of PIDIV
Instantiating from template now follows group seed -> spawn 1 correlation, including alpha move.
Differentiates static encounters that don't follow the ow8a correlation, scrambles EC to disassociate.
Adds rand64 to get initial seeds
Set correct level range to match slotSeed; not respecting the slot roll being valid, but whatever.
2022-04-22 21:11:11 -07:00

335 lines
10 KiB
C#

using System;
using System.Runtime.CompilerServices;
namespace PKHeX.Core;
/// <summary>
/// Contains logic for the Generation 8 (Legends: Arceus) overworld spawns that walk around the overworld.
/// </summary>
public static class Overworld8aRNG
{
private static uint GetShinyPID(int tid, int sid, uint pid, int type)
{
return (uint)(((tid ^ sid ^ (pid & 0xFFFF) ^ type) << 16) | (pid & 0xFFFF));
}
private static bool GetIsShiny(int tid, int sid, uint pid)
{
return GetShinyXor(pid, (uint)((sid << 16) | tid)) < 16;
}
private static uint GetShinyXor(uint pid, uint oid)
{
var xor = pid ^ oid;
return (xor ^ (xor >> 16)) & 0xFFFF;
}
private const int UNSET = -1;
public static (ulong GroupSeed, ulong SlotSeed) ApplyDetails(PKM pk, EncounterCriteria criteria, in OverworldParam8a para, bool giveAlphaMove)
{
int ctr = 0;
const int maxAttempts = 50_000;
var fakeRand = new Xoroshiro128Plus(Util.Rand.Rand64());
Xoroshiro128Plus groupRand;
ulong groupSeed;
ulong slotSeed;
do
{
groupSeed = fakeRand.Next();
groupRand = new Xoroshiro128Plus(groupSeed);
slotSeed = groupRand.Next();
var slotRand = new Xoroshiro128Plus(slotSeed);
_ = slotRand.Next();
var entitySeed = slotRand.Next();
var result = TryApplyFromSeed(pk, criteria, para, entitySeed);
if (result)
break;
} while (++ctr != maxAttempts);
// Failed, fall back to Unrestricted and just put whatever.
if (ctr >= maxAttempts)
{
groupSeed = fakeRand.Next();
groupRand = new Xoroshiro128Plus(groupSeed);
var slotRand = new Xoroshiro128Plus(slotSeed);
_ = slotRand.Next();
var entitySeed = slotRand.Next();
TryApplyFromSeed(pk, EncounterCriteria.Unrestricted, para, entitySeed);
}
if (giveAlphaMove)
ApplyRandomAlphaMove(pk, groupRand.Next());
return (groupSeed, slotSeed);
}
public static (ulong EntitySeed, ulong SlotRand) ApplyDetails(PKM pk, in OverworldParam8a para, bool giveAlphaMove, ref Xoroshiro128Plus groupRand)
{
var slotSeed = groupRand.Next();
var alphaSeed = groupRand.Next();
var slotRand = new Xoroshiro128Plus(slotSeed);
var slotRoll = slotRand.Next();
var entitySeed = slotRand.Next();
TryApplyFromSeed(pk, EncounterCriteria.Unrestricted, para, entitySeed);
if (giveAlphaMove)
ApplyRandomAlphaMove(pk, alphaSeed);
return (entitySeed, slotRoll);
}
private static void ApplyRandomAlphaMove(PKM pk, ulong seed)
{
var pi = (PersonalInfoLA)PersonalTable.LA.GetFormEntry(pk.Species, pk.Form);
var count = pi.GetMoveShopCount();
if (count == 0 || pk is not PA8 pa8)
return;
var index = GetRandomAlphaMoveIndex(seed, count);
var alphaIndex = pi.GetMoveShopIndex(index);
var alphaMove = Legal.MoveShop8_LA[alphaIndex];
pa8.SetMasteryFlagMove(pa8.AlphaMove = alphaMove);
}
private static int GetRandomAlphaMoveIndex(ulong alphaSeed, int count)
{
var alphaRand = new Xoroshiro128Plus(alphaSeed);
return (int)alphaRand.NextInt((uint)count);
}
public static bool TryApplyFromSeed(PKM pk, EncounterCriteria criteria, in OverworldParam8a para, ulong seed)
{
var rand = new Xoroshiro128Plus(seed);
// Encryption Constant
pk.EncryptionConstant = (uint)rand.NextInt();
// PID
var fakeTID = (uint)rand.NextInt();
uint pid = (uint)rand.NextInt();
bool isShiny = false;
if (para.Shiny == Shiny.Random) // let's decide if it's shiny or not!
{
for (int i = 1; i < para.RollCount; i++)
{
isShiny = GetShinyXor(pid, fakeTID) < 16;
if (isShiny)
break;
pid = (uint)rand.NextInt();
}
}
else
{
// no need to calculate a fake trainer
isShiny = para.Shiny == Shiny.Always;
}
ForceShinyState(pk, isShiny, ref pid);
if (para.Shiny == Shiny.Never)
{
if (GetIsShiny(pk.TID, pk.SID, pid))
return false;
}
else if (para.Shiny != Shiny.Random)
{
if (!GetIsShiny(pk.TID, pk.SID, pid))
return false;
if (para.Shiny == Shiny.AlwaysSquare && pk.ShinyXor != 0)
return false;
if (para.Shiny == Shiny.AlwaysStar && pk.ShinyXor == 0)
return false;
}
pk.PID = pid;
Span<int> ivs = stackalloc[] { UNSET, UNSET, UNSET, UNSET, UNSET, UNSET };
const int MAX = 31;
for (int i = 0; i < para.FlawlessIVs; i++)
{
int index;
do { index = (int)rand.NextInt(6); }
while (ivs[index] != UNSET);
ivs[index] = MAX;
}
for (int i = 0; i < ivs.Length; i++)
{
if (ivs[i] == UNSET)
ivs[i] = (int)rand.NextInt(32);
}
if (!criteria.IsIVsCompatible(ivs, 8))
return false;
pk.IV_HP = ivs[0];
pk.IV_ATK = ivs[1];
pk.IV_DEF = ivs[2];
pk.IV_SPA = ivs[3];
pk.IV_SPD = ivs[4];
pk.IV_SPE = ivs[5];
pk.RefreshAbility((int)rand.NextInt(2));
int gender = para.GenderRatio switch
{
PersonalInfo.RatioMagicGenderless => 2,
PersonalInfo.RatioMagicFemale => 1,
PersonalInfo.RatioMagicMale => 0,
_ => (int)rand.NextInt(252) + 1 < para.GenderRatio ? 1 : 0,
};
if (gender != criteria.Gender && criteria.Gender != -1)
return false;
pk.Gender = gender;
int nature = (int)rand.NextInt(25);
pk.StatNature = pk.Nature = nature;
var (height, weight) = para.IsAlpha
? (byte.MaxValue, byte.MaxValue)
: ((byte)((int)rand.NextInt(0x81) + (int)rand.NextInt(0x80)),
(byte)((int)rand.NextInt(0x81) + (int)rand.NextInt(0x80)));
if (pk is IScaledSize s)
{
s.HeightScalar = height;
s.WeightScalar = weight;
if (pk is IScaledSizeValue a)
{
a.ResetHeight();
a.ResetWeight();
}
}
return true;
}
public static bool Verify(PKM pk, ulong seed, in OverworldParam8a para)
{
var rand = new Xoroshiro128Plus(seed);
var ec = (uint)rand.NextInt();
if (ec != pk.EncryptionConstant)
return false;
var fakeTID = (uint)rand.NextInt();
uint pid = (uint)rand.NextInt();
bool isShiny = false;
if (para.Shiny == Shiny.Random) // let's decide if it's shiny or not!
{
for (int i = 1; i < para.RollCount; i++)
{
isShiny = GetShinyXor(pid, fakeTID) < 16;
if (isShiny)
break;
pid = (uint)rand.NextInt();
}
}
else
{
// no need to calculate a fake trainer
isShiny = para.Shiny == Shiny.Always;
}
ForceShinyState(pk, isShiny, ref pid);
if (pk.PID != pid)
return false;
Span<int> ivs = stackalloc[] { UNSET, UNSET, UNSET, UNSET, UNSET, UNSET };
const int MAX = 31;
for (int i = 0; i < para.FlawlessIVs; i++)
{
int index;
do { index = (int)rand.NextInt(6); }
while (ivs[index] != UNSET);
ivs[index] = MAX;
}
for (int i = 0; i < 6; i++)
{
if (ivs[i] == UNSET)
ivs[i] = (int)rand.NextInt(32);
}
if (pk.IV_HP != ivs[0])
return false;
if (pk.IV_ATK != ivs[1])
return false;
if (pk.IV_DEF != ivs[2])
return false;
if (pk.IV_SPA != ivs[3])
return false;
if (pk.IV_SPD != ivs[4])
return false;
if (pk.IV_SPE != ivs[5])
return false;
int abil = (int)rand.NextInt(2);
abil <<= 1; // 1/2/4
var current = pk.AbilityNumber;
if (abil == 4 && current != 4)
return false;
// else, for things that were made Hidden Ability, defer to Ability Checks (Ability Patch)
int gender = para.GenderRatio switch
{
PersonalInfo.RatioMagicGenderless => 2,
PersonalInfo.RatioMagicFemale => 1,
PersonalInfo.RatioMagicMale => 0,
_ => (int)rand.NextInt(252) + 1 < para.GenderRatio ? 1 : 0,
};
if (pk.Gender != gender)
return false;
var nature = (int)rand.NextInt(25);
if (pk.Nature != nature)
return false;
var (height, weight) = para.IsAlpha
? (byte.MaxValue, byte.MaxValue)
: ((byte)((int)rand.NextInt(0x81) + (int)rand.NextInt(0x80)),
(byte)((int)rand.NextInt(0x81) + (int)rand.NextInt(0x80)));
if (pk is IScaledSize s)
{
if (s.HeightScalar != height)
return false;
if (s.WeightScalar != weight)
return false;
}
return true;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void ForceShinyState(PKM pk, bool isShiny, ref uint pid)
{
if (isShiny)
{
if (!GetIsShiny(pk.TID, pk.SID, pid))
pid = GetShinyPID(pk.TID, pk.SID, pid, 0);
}
else
{
if (GetIsShiny(pk.TID, pk.SID, pid))
pid ^= 0x1000_0000;
}
}
public static int GetRandomLevel(ulong slotSeed, byte LevelMin, byte LevelMax)
{
var delta = LevelMax - LevelMin;
var xoro = new Xoroshiro128Plus(slotSeed);
xoro.Next();
xoro.Next(); // slot, entitySeed
var amp = (int)xoro.NextInt((ulong)delta + 1);
return LevelMin + amp;
}
}
public readonly record struct OverworldParam8a(bool IsAlpha, byte GenderRatio, byte FlawlessIVs, byte RollCount, Shiny Shiny = Shiny.Random);