PKHeX/PKHeX.Core/Legality/RNG/MethodFinder.cs
Kurt 103aa9aa4b
Revise EncounterArea and EncounterType for clarity (#3228)
EncounterArea now stores a more specific type'd array for encounter slots. Better iteration and less casting, as the nonspecific `Slots` fetch is rarely referenced.

EncounterType renamed to GroundTile to reflect how it actually works in Gen4. Was previously an ambiguous field that was clarified a little; we can describe it a little better now. Keep the GUI the same to not scare the end users.

Change Trash Byte properties to get/set a Span. Trash Byte legality checking easier on the garbage collector?
2021-06-29 20:58:06 -07:00

968 lines
36 KiB
C#

using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.CompilerServices;
using static PKHeX.Core.PIDType;
namespace PKHeX.Core
{
/// <summary>
/// Class containing logic to obtain a PKM's PIDIV method.
/// </summary>
public static class MethodFinder
{
/// <summary>
/// Analyzes a <see cref="PKM"/> to find a matching PIDIV method.
/// </summary>
/// <param name="pk">Input <see cref="PKM"/>.</param>
/// <returns><see cref="PIDIV"/> object containing seed and method info.</returns>
public static PIDIV Analyze(PKM pk)
{
if (pk.Format < 3)
return AnalyzeGB(pk);
var pid = pk.EncryptionConstant;
var top = pid >> 16;
var bot = pid & 0xFFFF;
var IVs = new uint[6];
for (int i = 0; i < 6; i++)
IVs[i] = (uint)pk.GetIV(i);
if (GetLCRNGMatch(top, bot, IVs, out PIDIV pidiv))
return pidiv;
if (pk.Species == (int)Species.Unown && GetLCRNGUnownMatch(top, bot, IVs, out pidiv)) // frlg only
return pidiv;
if (GetColoStarterMatch(pk, top, bot, IVs, out pidiv))
return pidiv;
if (GetXDRNGMatch(pk, top, bot, IVs, out pidiv))
return pidiv;
// Special cases
if (GetLCRNGRoamerMatch(top, bot, IVs, out pidiv))
return pidiv;
if (GetChannelMatch(top, bot, IVs, out pidiv, pk))
return pidiv;
if (GetMG4Match(pid, IVs, out pidiv))
return pidiv;
if (GetBACDMatch(pk, pid, IVs, out pidiv))
return pidiv;
if (GetModifiedPIDMatch(pk, pid, IVs, out pidiv))
return pidiv;
return PIDIV.None; // no match
}
private static bool GetModifiedPIDMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
if (pk.IsShiny)
{
if (GetChainShinyMatch(pk, pid, IVs, out pidiv))
return true;
if (GetModified8BitMatch(pk, pid, out pidiv))
return true;
}
else
{
if (pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv))
return true;
}
return GetPokewalkerMatch(pk, pid, out pidiv);
}
private static bool GetModified8BitMatch(PKM pk, uint pid, out PIDIV pidiv)
{
return pk.Gen4
? (pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv)) || GetG5MGShinyMatch(pk, pid, out pidiv)
: GetG5MGShinyMatch(pk, pid, out pidiv) || (pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv));
}
private static bool GetLCRNGMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
var reg = GetSeedsFromPID(RNG.LCRNG, top, bot);
var iv1 = GetIVChunk(IVs, 0);
var iv2 = GetIVChunk(IVs, 3);
foreach (var seed in reg)
{
// A and B are already used by PID
var B = RNG.LCRNG.Advance(seed, 2);
// Method 1/2/4 can use 3 different RNG frames
var C = RNG.LCRNG.Next(B);
var ivC = C >> 16 & 0x7FFF;
if (iv1 == ivC)
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv2 == ivD) // ABCD
{
pidiv = new PIDIV(Method_1, seed);
return true;
}
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // ABCE
{
pidiv = new PIDIV(Method_4, seed);
return true;
}
}
else
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // ABDE
{
pidiv = new PIDIV(Method_2, seed);
return true;
}
}
}
reg = GetSeedsFromPIDSkip(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
// A and B are already used by PID
var C = RNG.LCRNG.Advance(seed, 3);
// Method 3
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 != ivE)
continue;
pidiv = new PIDIV(Method_3, seed);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetLCRNGUnownMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
// this is an exact copy of LCRNG 1,2,4 matching, except the PID has its halves switched (BACD, BADE, BACE)
var reg = GetSeedsFromPID(RNG.LCRNG, bot, top); // reversed!
var iv1 = GetIVChunk(IVs, 0);
var iv2 = GetIVChunk(IVs, 3);
foreach (var seed in reg)
{
// A and B are already used by PID
var B = RNG.LCRNG.Advance(seed, 2);
// Method 1/2/4 can use 3 different RNG frames
var C = RNG.LCRNG.Next(B);
var ivC = C >> 16 & 0x7FFF;
if (iv1 == ivC)
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv2 == ivD) // BACD
{
pidiv = new PIDIV(Method_1_Unown, seed);
return true;
}
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // BACE
{
pidiv = new PIDIV(Method_4_Unown, seed);
return true;
}
}
else
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // BADE
{
pidiv = new PIDIV(Method_2_Unown, seed);
return true;
}
}
}
reg = GetSeedsFromPIDSkip(RNG.LCRNG, bot, top); // reversed!
foreach (var seed in reg)
{
// A and B are already used by PID
var C = RNG.LCRNG.Advance(seed, 3);
// Method 3
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 != ivE)
continue;
pidiv = new PIDIV(Method_3_Unown, seed);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetLCRNGRoamerMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
if (IVs[2] != 0 || IVs[3] != 0 || IVs[4] != 0 || IVs[5] != 0 || IVs[1] > 7)
return GetNonMatch(out pidiv);
var iv1 = GetIVChunk(IVs, 0);
var reg = GetSeedsFromPID(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
// Only the first 8 bits are kept
var ivC = RNG.LCRNG.Advance(seed, 3) >> 16 & 0x00FF;
if (iv1 != ivC)
continue;
pidiv = new PIDIV(Method_1_Roamer, seed);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetXDRNGMatch(PKM pk, uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
var xdc = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in xdc)
{
var B = RNG.XDRNG.Prev(seed);
var A = RNG.XDRNG.Prev(B);
var hi = A >> 16;
var lo = B >> 16;
if (IVsMatch(hi, lo, IVs))
{
pidiv = new PIDIV(CXD, RNG.XDRNG.Prev(A));
return true;
}
// check for anti-shiny against player TSV
var tsv = (uint)(pk.TID ^ pk.SID) >> 3;
var psv = (top ^ bot) >> 3;
if (psv == tsv) // already shiny, wouldn't be anti-shiny
continue;
var p2 = seed;
var p1 = B;
psv = ((p2 ^ p1) >> 19);
if (psv != tsv) // prior PID must be shiny
continue;
do
{
B = RNG.XDRNG.Prev(A);
A = RNG.XDRNG.Prev(B);
hi = A >> 16;
lo = B >> 16;
if (IVsMatch(hi, lo, IVs))
{
pidiv = new PIDIV(CXDAnti, RNG.XDRNG.Prev(A));
return true;
}
p2 = RNG.XDRNG.Prev(p1);
p1 = RNG.XDRNG.Prev(p2);
psv = (p2 ^ p1) >> 19;
}
while (psv == tsv);
}
return GetNonMatch(out pidiv);
}
private static bool GetChannelMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv, PKM pk)
{
var ver = pk.Version;
if (ver is not ((int)GameVersion.R or (int)GameVersion.S))
return GetNonMatch(out pidiv);
var undo = top ^ 0x8000;
if ((undo > 7 ? 0 : 1) != (bot ^ pk.SID ^ 40122))
top = undo;
var channel = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in channel)
{
var C = RNG.XDRNG.Advance(seed, 3); // held item
// no checks, held item can be swapped
var D = RNG.XDRNG.Next(C); // Version
if ((D >> 31) + 1 != ver) // (0-Sapphire, 1-Ruby)
continue;
var E = RNG.XDRNG.Next(D); // OT Gender
if (E >> 31 != pk.OT_Gender)
continue;
if (!RNG.XDRNG.GetSequentialIVsUInt32(E).SequenceEqual(IVs))
continue;
if (seed >> 16 != pk.SID)
continue;
pidiv = new PIDIV(Channel, RNG.XDRNG.Prev(seed));
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetMG4Match(uint pid, uint[] IVs, out PIDIV pidiv)
{
uint mg4Rev = RNG.ARNG.Prev(pid);
var mg4 = GetSeedsFromPID(RNG.LCRNG, mg4Rev >> 16, mg4Rev & 0xFFFF);
foreach (var seed in mg4)
{
var B = RNG.LCRNG.Advance(seed, 2);
var C = RNG.LCRNG.Next(B);
var D = RNG.LCRNG.Next(C);
if (!IVsMatch(C >> 16, D >> 16, IVs))
continue;
pidiv = new PIDIV(G4MGAntiShiny, seed);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetG5MGShinyMatch(PKM pk, uint pid, out PIDIV pidiv)
{
var low = pid & 0xFFFF;
// generation 5 shiny PIDs
if (low <= 0xFF)
{
var av = (pid >> 16) & 1;
var genPID = PIDGenerator.GetMG5ShinyPID(low, av, pk.TID, pk.SID);
if (genPID == pid)
{
pidiv = PIDIV.G5MGShiny;
return true;
}
}
return GetNonMatch(out pidiv);
}
private static bool GetCuteCharmMatch(PKM pk, uint pid, out PIDIV pidiv)
{
if (pid > 0xFF)
return GetNonMatch(out pidiv);
GetCuteCharmGenderSpecies(pk, pid, out int genderValue, out int species);
int getRatio() => PersonalTable.HGSS[species].Gender;
switch (genderValue)
{
case 2: break; // can't cute charm a genderless pkm
case 0: // male
var gr = getRatio();
if (254 <= gr) // no modification for PID
break;
var rate = 25*((gr / 25) + 1); // buffered
var nature = pid % 25;
if (nature + rate != pid)
break;
pidiv = PIDIV.CuteCharm;
return true;
case 1: // female
if (pid >= 25)
break; // nope, this isn't a valid nature
if (254 <= getRatio()) // no modification for PID
break;
pidiv = PIDIV.CuteCharm;
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetChainShinyMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
// 13 shiny bits
// PIDH & 7
// PIDL & 7
// IVs
var bot = GetIVChunk(IVs, 0);
var top = GetIVChunk(IVs, 3);
var reg = GetSeedsFromIVs(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
// check the individual bits
var s = seed;
int i = 15;
do
{
var bit = s >> 16 & 1;
if (bit != (pid >> i & 1))
break;
s = RNG.LCRNG.Prev(s);
}
while (--i != 2);
if (i != 2) // bit failed
continue;
// Shiny Bits of PID validated
var upper = s;
if ((upper >> 16 & 7) != (pid >> 16 & 7))
continue;
var lower = RNG.LCRNG.Prev(upper);
if ((lower >> 16 & 7) != (pid & 7))
continue;
var upid = (((pid & 0xFFFF) ^ pk.TID ^ pk.SID) & 0xFFF8) | ((upper >> 16) & 0x7);
if (upid != pid >> 16)
continue;
s = RNG.LCRNG.Reverse(lower, 2); // unroll one final time to get the origin seed
pidiv = new PIDIV(ChainShiny, s);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetBACDMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
var bot = GetIVChunk(IVs, 0);
var top = GetIVChunk(IVs, 3);
var reg = GetSeedsFromIVs(RNG.LCRNG, top, bot);
PIDType type = BACD_U;
foreach (var seed in reg)
{
var B = seed;
var A = RNG.LCRNG.Prev(B);
var low = B >> 16;
var PID = (A & 0xFFFF0000) | low;
if (PID != pid)
{
uint idxor = (uint)(pk.TID ^ pk.SID);
bool isShiny = (idxor ^ PID >> 16 ^ (PID & 0xFFFF)) < 8;
if (!isShiny)
{
if (!pk.IsShiny) // check for nyx antishiny
{
if (!IsBACD_U_AX(idxor, pid, low, A, ref type))
continue;
}
else // check for force shiny pkm
{
if (!IsBACD_U_S(idxor, pid, low, ref A, ref type))
continue;
}
}
else if (!IsBACD_U_AX(idxor, pid, low, A, ref type))
{
if ((PID + 8 & 0xFFFFFFF8) != pid)
continue;
type = BACD_U_A;
}
}
var s = RNG.LCRNG.Prev(A);
// Check for prior Restricted seed
var sn = s;
for (int i = 0; i < 3; i++, sn = RNG.LCRNG.Prev(sn))
{
if ((sn & 0xFFFF0000) != 0)
continue;
// shift from unrestricted enum val to restricted enum val
pidiv = new PIDIV(--type, sn);
return true;
}
// no restricted seed found, thus unrestricted
pidiv = new PIDIV(type, s);
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetPokewalkerMatch(PKM pk, uint oldpid, out PIDIV pidiv)
{
// check surface compatibility
var mid = oldpid & 0x00FFFF00;
if (mid != 0 && mid != 0x00FFFF00) // not expected bits
return GetNonMatch(out pidiv);
var nature = oldpid % 25;
if (nature == 24) // impossible nature
return GetNonMatch(out pidiv);
var gender = pk.Gender;
uint pid = PIDGenerator.GetPokeWalkerPID(pk.TID, pk.SID, nature, gender, pk.PersonalInfo.Gender);
if (pid != oldpid)
{
if (!(gender == 0 && IsAzurillEdgeCaseM(pk, nature, oldpid)))
return GetNonMatch(out pidiv);
}
pidiv = PIDIV.Pokewalker;
return true;
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool IsAzurillEdgeCaseM(PKM pk, uint nature, uint oldpid)
{
// check for Azurill evolution edge case... 75% F-M is now 50% F-M; was this a F->M bend?
int species = pk.Species;
if (species is not ((int)Species.Marill or (int)Species.Azumarill))
return false;
const int AzurillGenderRatio = 0xBF;
var gender = PKX.GetGenderFromPIDAndRatio(pk.PID, AzurillGenderRatio);
if (gender != 1)
return false;
var pid = PIDGenerator.GetPokeWalkerPID(pk.TID, pk.SID, nature, 1, AzurillGenderRatio);
return pid == oldpid;
}
private static bool GetColoStarterMatch(PKM pk, uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
if (pk.Version != (int)GameVersion.CXD || pk.Species is not ((int)Species.Espeon or (int)Species.Umbreon))
return GetNonMatch(out pidiv);
var iv1 = GetIVChunk(IVs, 0);
var iv2 = GetIVChunk(IVs, 3);
var xdc = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in xdc)
{
uint origin = seed;
if (!LockFinder.IsColoStarterValid(pk.Species, ref origin, pk.TID, pk.SID, pk.PID, iv1, iv2))
continue;
pidiv = new PIDIV(CXD_ColoStarter, origin);
return true;
}
return GetNonMatch(out pidiv);
}
/// <summary>
/// Returns false and no <see cref="PIDIV"/>.
/// </summary>
/// <param name="pidiv">Null</param>
/// <returns>False</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool GetNonMatch(out PIDIV pidiv)
{
pidiv = PIDIV.None;
return false;
}
/// <summary>
/// Checks if the PID is a <see cref="PIDType.BACD_U_S"></see> match.
/// </summary>
/// <param name="idxor"><see cref="PKM.TID"/> ^ <see cref="PKM.SID"/></param>
/// <param name="pid">Full actual PID</param>
/// <param name="low">Low portion of PID (B)</param>
/// <param name="A">First RNG call</param>
/// <param name="type">PID Type is updated if successful</param>
/// <returns>True/False if the PID matches</returns>
/// <remarks>First RNG call is unrolled once if the PID is valid with this correlation</remarks>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool IsBACD_U_S(uint idxor, uint pid, uint low, ref uint A, ref PIDType type)
{
// 0-Origin
// 1-PIDH
// 2-PIDL (ends up unused)
// 3-FORCEBITS
// PID = PIDH << 16 | (SID ^ TID ^ PIDH)
var X = RNG.LCRNG.Prev(A); // unroll once as there's 3 calls instead of 2
uint PID = (X & 0xFFFF0000) | (idxor ^ X >> 16);
PID &= 0xFFFFFFF8;
PID |= low & 0x7; // lowest 3 bits
if (PID != pid)
return false;
A = X; // keep the unrolled seed
type = BACD_U_S;
return true;
}
/// <summary>
/// Checks if the PID is a <see cref="PIDType.BACD_U_AX"></see> match.
/// </summary>
/// <param name="idxor"><see cref="PKM.TID"/> ^ <see cref="PKM.SID"/></param>
/// <param name="pid">Full actual PID</param>
/// <param name="low">Low portion of PID (B)</param>
/// <param name="A">First RNG call</param>
/// <param name="type">PID Type is updated if successful</param>
/// <returns>True/False if the PID matches</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool IsBACD_U_AX(uint idxor, uint pid, uint low, uint A, ref PIDType type)
{
if ((pid & 0xFFFF) != low)
return false;
// 0-Origin
// 1-ushort rnd, do until >8
// 2-PIDL
uint rnd = A >> 16;
if (rnd < 8)
return false;
uint PID = ((rnd ^ idxor ^ low) << 16) | low;
if (PID != pid)
return false;
type = BACD_U_AX;
return true;
}
private static PIDIV AnalyzeGB(PKM _)
{
// not implemented; correlation between IVs and RNG hasn't been converted to code.
return PIDIV.None;
}
private static IEnumerable<uint> GetSeedsFromPID(RNG method, uint a, uint b)
{
Debug.Assert(a >> 16 == 0);
Debug.Assert(b >> 16 == 0);
uint second = a << 16;
uint first = b << 16;
return method.RecoverLower16Bits(first, second);
}
private static IEnumerable<uint> GetSeedsFromPIDSkip(RNG method, uint a, uint b)
{
Debug.Assert(a >> 16 == 0);
Debug.Assert(b >> 16 == 0);
uint third = a << 16;
uint first = b << 16;
return method.RecoverLower16BitsGap(first, third);
}
private static IEnumerable<uint> GetSeedsFromIVs(RNG method, uint a, uint b)
{
Debug.Assert(a >> 15 == 0);
Debug.Assert(b >> 15 == 0);
uint second = a << 16;
uint first = b << 16;
var pairs = method.RecoverLower16Bits(first, second)
.Concat(method.RecoverLower16Bits(first, second ^ 0x80000000));
foreach (var z in pairs)
{
yield return z;
yield return z ^ 0x80000000; // sister bitflip
}
}
public static IEnumerable<uint> GetSeedsFromIVsSkip(RNG method, uint rand1, uint rand3)
{
Debug.Assert(rand1 >> 15 == 0);
Debug.Assert(rand3 >> 15 == 0);
rand1 <<= 16;
rand3 <<= 16;
var seeds = method.RecoverLower16BitsGap(rand1, rand3)
.Concat(method.RecoverLower16BitsGap(rand1, rand3 ^ 0x80000000));
foreach (var z in seeds)
{
yield return z;
yield return z ^ 0x80000000; // sister bitflip
}
}
public static IEnumerable<uint> GetSeedsFromPIDEuclid(RNG method, uint rand1, uint rand2)
{
return method.RecoverLower16BitsEuclid16(rand1 << 16, rand2 << 16);
}
public static IEnumerable<uint> GetSeedsFromIVsEuclid(RNG method, uint rand1, uint rand2)
{
return method.RecoverLower16BitsEuclid15(rand1 << 16, rand2 << 16);
}
/// <summary>
/// Generates IVs from 2 RNG calls using 15 bits of each to generate 6 IVs (5bits each).
/// </summary>
/// <param name="r1">First rand frame</param>
/// <param name="r2">Second rand frame</param>
/// <param name="IVs">IVs that should be the result</param>
/// <returns>IVs match random number IVs</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool IVsMatch(uint r1, uint r2, IReadOnlyList<uint> IVs)
{
if (IVs[0] != (r1 & 31))
return false;
if (IVs[1] != (r1 >> 5 & 31))
return false;
if (IVs[2] != (r1 >> 10 & 31))
return false;
if (IVs[3] != (r2 & 31))
return false;
if (IVs[4] != (r2 >> 5 & 31))
return false;
if (IVs[5] != (r2 >> 10 & 31))
return false;
return true;
}
/// <summary>
/// Generates IVs from 2 RNG calls using 15 bits of each to generate 6 IVs (5bits each).
/// </summary>
/// <param name="r1">First rand frame</param>
/// <param name="r2">Second rand frame</param>
/// <returns>Array of 6 IVs</returns>
internal static uint[] GetIVs(uint r1, uint r2)
{
return new[]
{
r1 & 31,
r1 >> 5 & 31,
r1 >> 10 & 31,
r2 & 31,
r2 >> 5 & 31,
r2 >> 10 & 31,
};
}
internal static int[] GetIVsInt32(uint r1, uint r2)
{
return new[]
{
(int)r1 & 31,
(int)r1 >> 5 & 31,
(int)r1 >> 10 & 31,
(int)r2 & 31,
(int)r2 >> 5 & 31,
(int)r2 >> 10 & 31,
};
}
private static uint GetIVChunk(uint[] IVs, int start)
{
uint val = 0;
for (int i = 0; i < 3; i++)
val |= IVs[i+start] << (5*i);
return val;
}
public static IEnumerable<PIDIV> GetColoEReaderMatches(uint PID)
{
var top = PID >> 16;
var bot = (ushort)PID;
var xdc = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in xdc)
{
var B = RNG.XDRNG.Prev(seed);
var A = RNG.XDRNG.Prev(B);
var C = RNG.XDRNG.Advance(A, 7);
yield return new PIDIV(CXD, RNG.XDRNG.Prev(C));
}
}
public static IEnumerable<PIDIV> GetPokeSpotSeeds(PKM pkm, int slot)
{
// Activate (rand % 3)
// Munchlax / Bonsly (10%/30%)
// Encounter Slot Value (ESV) = 50%/35%/15% rarity (0-49, 50-84, 85-99)
var pid = pkm.PID;
var top = pid >> 16;
var bot = pid & 0xFFFF;
var seeds = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in seeds)
{
// check for valid encounter slot info
if (!IsPokeSpotActivation(slot, seed, out uint s))
continue;
yield return new PIDIV(PokeSpot, s);
}
}
public static bool IsPokeSpotActivation(int slot, uint seed, out uint s)
{
s = seed;
var esv = (seed >> 16) % 100;
if (!IsPokeSpotSlotValid(slot, esv))
{
// todo
}
// check for valid activation
s = RNG.XDRNG.Prev(seed);
if ((s >> 16) % 3 != 0)
{
if ((s >> 16) % 100 < 10) // can't fail a munchlax/bonsly encounter check
{
// todo
}
s = RNG.XDRNG.Prev(s);
if ((s >> 16) % 3 != 0) // can't activate even if generous
{
// todo
}
}
return true;
}
private static bool IsPokeSpotSlotValid(int slot, uint esv) => slot switch
{
0 => esv < 50 , // [0,50)
1 => esv - 50 < 35, // [50,85)
2 => esv >= 85, // [85,100)
_ => false
};
public static bool IsCompatible3(this PIDType val, IEncounterable encounter, PKM pkm)
{
switch (encounter)
{
case WC3 g:
if (val == g.Method)
return true;
if (val == CXDAnti && g.Shiny == Shiny.Never && g.Method == CXD)
return true;
// forced shiny eggs, when hatched, can lose their detectable correlation.
return g.IsEgg && !pkm.IsEgg && val == None && (g.Method is BACD_R_S or BACD_U_S);
case EncounterStaticShadow:
return pkm.Version == (int)GameVersion.CXD && (val is CXD or CXDAnti);
case EncounterStatic3 s:
return pkm.Version switch
{
(int)GameVersion.CXD => val is CXD or CXD_ColoStarter or CXDAnti,
(int)GameVersion.E => val == Method_1, // no roamer glitch
(int)GameVersion.FR or (int)GameVersion.LG => s.Roaming ? val.IsRoamerPIDIV(pkm) : val == Method_1, // roamer glitch
_ => s.Roaming ? val.IsRoamerPIDIV(pkm) : MethodH14.Contains(val), // RS, roamer glitch && RSBox s/w emulation => method 4 available
};
case EncounterSlot w:
if (pkm.Version == 15)
return val == PokeSpot;
return (w.Species == (int)Species.Unown ? MethodH_Unown : MethodH).Contains(val);
default:
return val == None;
}
}
private static bool IsRoamerPIDIV(this PIDType val, PKM pkm)
{
// Roamer PIDIV is always Method 1.
// M1 is checked before M1R. A M1R PIDIV can also be a M1 PIDIV, so check that collision.
if (Method_1_Roamer == val)
return true;
if (Method_1 != val)
return false;
// only 8 bits are stored instead of 32 -- 5 bits HP, 3 bits for ATK.
// return pkm.IV32 <= 0xFF;
return pkm.IV_DEF == 0 && pkm.IV_SPE == 0 && pkm.IV_SPA == 0 && pkm.IV_SPD == 0 && pkm.IV_ATK <= 7;
}
public static bool IsCompatible4(this PIDType val, IEncounterable encounter, PKM pkm)
{
switch (encounter)
{
case EncounterStatic4Pokewalker:
return val == Pokewalker || (val == CuteCharm && GetCuteCharmMatch(pkm, pkm.EncryptionConstant, out _) && IsCuteCharm4Valid(encounter, pkm));
case EncounterStatic4 {Species: (int)Species.Pichu}:
return val == Pokewalker;
case EncounterStatic4 {Shiny: Shiny.Always}:
return val == ChainShiny;
case EncounterStatic4:
if (val == CuteCharm && IsCuteCharm4Valid(encounter, pkm))
return true;
return val == Method_1;
case EncounterSlot4 sl:
if (val == Method_1)
return true;
if (val == CuteCharm && IsCuteCharm4Valid(encounter, pkm))
return true;
if (val != ChainShiny)
return false;
// Chain shiny with poke radar is only possible in DPPt in grass, safari zone does not allow pokeradar
// TypeEncounter Grass discard any cave or city
return pkm.IsShiny && !pkm.HGSS && sl.GroundTile == GroundTilePermission.Grass && !Locations.IsSafariZoneLocation4(sl.Location);
case PGT: // manaphy
return IsG4ManaphyPIDValid(val, pkm);
case PCD d when d.Gift.PK.PID != 1:
return true; // already matches PCD's fixed PID requirement
default: // eggs
return val == None;
}
}
private static bool IsG4ManaphyPIDValid(PIDType val, PKM pkm)
{
if (pkm.IsEgg)
{
if (pkm.IsShiny)
return false;
if (val == Method_1)
return true;
return val == G4MGAntiShiny && IsAntiShinyARNG();
}
if (val == Method_1)
return pkm.WasTradedEgg || !pkm.IsShiny; // can't be shiny on received game
return val == G4MGAntiShiny && (pkm.WasTradedEgg || IsAntiShinyARNG());
bool IsAntiShinyARNG()
{
var shinyPID = RNG.ARNG.Prev(pkm.PID);
return (pkm.TID ^ pkm.SID ^ (shinyPID & 0xFFFF) ^ (shinyPID >> 16)) < 8; // shiny proc
}
}
private static bool IsCuteCharm4Valid(IEncounterable encounter, PKM pkm)
{
if (pkm.Species is (int)Species.Marill or (int)Species.Azumarill)
{
return !IsCuteCharmAzurillMale(pkm.PID) // recognized as not Azurill
|| encounter.Species == (int)Species.Azurill; // encounter must be male Azurill
}
return true;
}
private static bool IsCuteCharmAzurillMale(uint pid) => pid is >= 0xC8 and <= 0xE0;
private static void GetCuteCharmGenderSpecies(PKM pk, uint pid, out int genderValue, out int species)
{
// There are some edge cases when the gender ratio changes across evolutions.
species = pk.Species;
if (species == (int)Species.Ninjask)
{
species = (int)Species.Nincada; // Nincada evo chain travels from M/F -> Genderless Shedinja
genderValue = PKX.GetGenderFromPID(species, pid);
return;
}
switch (species)
{
// These evolved species cannot be encountered with cute charm.
// 100% fixed gender does not modify PID; override this with the encounter species for correct calculation.
// We can assume the re-mapped species's [gender ratio] is what was encountered.
case (int)Species.Wormadam or (int)Species.Mothim: species = (int)Species.Burmy; break;
case (int)Species.Vespiquen: species = (int)Species.Combee; break;
case (int)Species.Gallade: species = (int)Species.Kirlia; break;
case (int)Species.Froslass: species = (int)Species.Snorunt; break;
// Changed gender ratio (25% M -> 50% M) needs special treatment.
// Double check the encounter species with IsCuteCharm4Valid afterwards.
case (int)Species.Marill or (int)Species.Azumarill: // Azurill & Marill/Azumarill collision
if (IsCuteCharmAzurillMale(pid))
{
species = (int)Species.Azurill;
genderValue = 0;
return;
}
break;
}
genderValue = pk.Gender;
}
private static readonly PIDType[] MethodH = { Method_1, Method_2, Method_3, Method_4 };
private static readonly PIDType[] MethodH14 = { Method_1, Method_4 };
private static readonly PIDType[] MethodH_Unown = { Method_1_Unown, Method_2_Unown, Method_3_Unown, Method_4_Unown };
}
}