Add targeted generator methods for CXD pidiv

If IVs are specified, will try to search for all seeds that originate them.
Same as was done for Method H/J/K of mainline games, this allows sets to be more-quickly generated if the criteria is provided.

PKHeX.Core/Legality/Encounters/Templates/Gen3/Colo/EncounterGift3Colo.cs

@@ -42,8 +42,6 @@ public sealed record EncounterGift3Colo : IEncounterable, IEncounterMatch, IEnco
     public byte LevelMin => Level;
     public byte LevelMax => Level;
 
-    public bool IsColoStarter => Species is (ushort)Core.Species.Espeon or (ushort)Core.Species.Umbreon;
-
     #region Generating
     PKM IEncounterConvertible.ConvertToPKM(ITrainerInfo tr, EncounterCriteria criteria) => ConvertToPKM(tr, criteria);
     PKM IEncounterConvertible.ConvertToPKM(ITrainerInfo tr) => ConvertToPKM(tr);
@@ -90,6 +88,9 @@ public sealed record EncounterGift3Colo : IEncounterable, IEncounterMatch, IEnco
 
     private void SetPINGA(CK3 pk, EncounterCriteria criteria, PersonalInfo3 pi)
     {
+        if (criteria.IsSpecifiedIVs() && MethodCXD.SetFromIVsCXD(pk, criteria, pi, Shiny == Shiny.Never))
+            return;
+
         var gender = criteria.GetGender(pi);
         var nature = criteria.GetNature();
         var ability = criteria.GetAbilityFromNumber(Ability);
@@ -156,12 +157,7 @@ public sealed record EncounterGift3Colo : IEncounterable, IEncounterMatch, IEnco
     }
     #endregion
 
-    public bool IsCompatible(PIDType val, PKM pk)
+    public bool IsCompatible(PIDType val, PKM pk) => val is PIDType.CXD;
-    {
-        if (IsColoStarter)
-            return val is PIDType.CXD_ColoStarter;
-        return val is PIDType.CXD;
-    }
 
     public PIDType GetSuggestedCorrelation() => PIDType.CXD;
 

PKHeX.Core/Legality/Encounters/Templates/Gen3/Colo/EncounterShadow3Colo.cs

@@ -89,6 +89,9 @@ public sealed record EncounterShadow3Colo(byte ID, short Gauge, ReadOnlyMemory<T
 
     private void SetPINGA_Regular(CK3 pk, EncounterCriteria criteria, PersonalInfo3 pi)
     {
+        if (criteria.IsSpecifiedIVs() && this.SetFromIVs(pk, criteria, pi))
+            return;
+
         var gender = criteria.GetGender(pi);
         var nature = criteria.GetNature();
         int ability = criteria.GetAbilityFromNumber(Ability);
@@ -107,8 +110,6 @@ public sealed record EncounterShadow3Colo(byte ID, short Gauge, ReadOnlyMemory<T
                 break;
         }
         while (++ctr <= max);
-
-        System.Diagnostics.Debug.Assert(ctr < max);
     }
 
     private void SetPINGA_EReader(CK3 pk)

PKHeX.Core/Legality/Encounters/Templates/Gen3/Colo/EncounterStatic3Colo.cs

@@ -71,6 +71,9 @@ public sealed record EncounterStatic3Colo(ushort Species, byte Level)
 
     private void SetPINGA(CK3 pk, EncounterCriteria criteria, PersonalInfo3 pi)
     {
+        if (MethodCXD.SetFromTrainerIDStarter(pk, criteria, pi, pk.TID16, pk.SID16))
+            return;
+
         var gender = criteria.GetGender(Gender, pi);
         var nature = criteria.GetNature();
         var ability = criteria.GetAbilityFromNumber(Ability);

PKHeX.Core/Legality/Encounters/Templates/Gen3/XD/EncounterShadow3XD.cs

@@ -79,6 +79,9 @@ public sealed record EncounterShadow3XD(byte ID, short Gauge, ReadOnlyMemory<Tea
 
     private void SetPINGA(XK3 pk, EncounterCriteria criteria, PersonalInfo3 pi)
     {
+        if (criteria.IsSpecifiedIVs() && this.SetFromIVs(pk, criteria, pi, noShiny: true))
+            return;
+
         var gender = criteria.GetGender(pi);
         var nature = criteria.GetNature();
         int ability = criteria.GetAbilityFromNumber(Ability);

PKHeX.Core/Legality/Encounters/Templates/Gen3/XD/EncounterStatic3XD.cs

@@ -29,8 +29,6 @@ public sealed record EncounterStatic3XD(ushort Species, byte Level)
     public byte LevelMin => Level;
     public byte LevelMax => Level;
 
-    public bool IsColoStarter => Species is (ushort)Core.Species.Espeon or (ushort)Core.Species.Umbreon;
-
     #region Generating
     PKM IEncounterConvertible.ConvertToPKM(ITrainerInfo tr, EncounterCriteria criteria) => ConvertToPKM(tr, criteria);
     PKM IEncounterConvertible.ConvertToPKM(ITrainerInfo tr) => ConvertToPKM(tr);
@@ -71,6 +69,16 @@ public sealed record EncounterStatic3XD(ushort Species, byte Level)
 
     private void SetPINGA(XK3 pk, EncounterCriteria criteria, PersonalInfo3 pi)
     {
+        if (Species == (int)Core.Species.Eevee)
+        {
+            if (MethodCXD.SetFromTrainerIDStarter(pk, criteria, pi, pk.TID16, pk.SID16))
+                return;
+        }
+        else
+        {
+            if (criteria.IsSpecifiedIVs() && MethodCXD.SetFromIVsCXD(pk, criteria, pi, noShiny: true))
+                return;
+        }
         var gender = criteria.GetGender(pi);
         var nature = criteria.GetNature();
         var ability = criteria.GetAbilityFromNumber(Ability);
@@ -137,8 +145,6 @@ public sealed record EncounterStatic3XD(ushort Species, byte Level)
 
     public bool IsCompatible(PIDType val, PKM pk)
     {
-        if (IsColoStarter)
-            return val is PIDType.CXD_ColoStarter;
         if (val is PIDType.CXD)
             return true;
         return val is PIDType.CXDAnti && FatefulEncounter;

PKHeX.Core/Legality/RNG/CXD/MethodCXD.cs

@@ -0,0 +1,190 @@
+using System;
+
+namespace PKHeX.Core;
+
+/// <summary>
+/// Generator methods for <see cref="GameVersion.CXD"/>.
+/// </summary>
+public static class MethodCXD
+{
+    /// <summary>
+    /// Tries to set a valid PID/IV for the requested criteria for an <see cref="IShadow3"/> object.
+    /// </summary>
+    /// <remarks>Only called if <see cref="EncounterCriteria.IsSpecifiedIVs"/> is true.</remarks>
+    public static bool SetFromIVs<T>(this T enc, G3PKM pk, EncounterCriteria criteria, PersonalInfo3 pi, bool noShiny = false) where T : IShadow3
+    {
+        var gr = pi.Gender;
+        (uint iv1, uint iv2) = GetCombinedIVs(criteria);
+        Span<uint> all = stackalloc uint[XDRNG.MaxCountSeedsIV];
+        var count = XDRNG.GetSeedsIVs(all, iv1 << 16, iv2 << 16);
+        var seeds = all[..count];
+        foreach (var seed in seeds)
+        {
+            // * => IV, IV, ability, PID, PID
+            var s = XDRNG.Next3(seed);
+            uint pid = GetPID(pk, s, noShiny);
+            if (criteria.IsSpecifiedNature() && (Nature)(pid % 25) != criteria.Nature)
+                continue;
+
+            var gender = EntityGender.GetFromPIDAndRatio(pid, gr);
+            if (!criteria.IsGenderSatisfied(gender))
+                continue;
+
+            var origin = XDRNG.Prev(seed);
+            var pidiv = new PIDIV(PIDType.CXD, origin);
+            var result = LockFinder.IsAllShadowLockValid(enc, pidiv, pk);
+            if (!result)
+                continue;
+
+            pk.PID = pid;
+            pk.Ability = ((XDRNG.Next2(seed) >> 16) & 1) == 0 ? pi.Ability1 : pi.Ability2;
+            criteria.SetRandomIVs(pk);
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// Tries to set a valid PID/IV for the requested criteria for a non-shadow encounter.
+    /// </summary>
+    /// <remarks>Only called if <see cref="EncounterCriteria.IsSpecifiedIVs"/> is true.</remarks>
+    public static bool SetFromIVsCXD(G3PKM pk, EncounterCriteria criteria, PersonalInfo3 pi, bool noShiny = true)
+    {
+        var gr = pi.Gender;
+        (uint iv1, uint iv2) = GetCombinedIVs(criteria);
+        Span<uint> all = stackalloc uint[XDRNG.MaxCountSeedsIV];
+        var count = XDRNG.GetSeedsIVs(all, iv1 << 16, iv2 << 16);
+        var seeds = all[..count];
+        foreach (var seed in seeds)
+        {
+            // * => IV, IV, ability, PID, PID
+            var s = XDRNG.Next3(seed);
+            uint pid = GetPID(pk, s, noShiny);
+            if (criteria.IsSpecifiedNature() && (Nature)(pid % 25) != criteria.Nature)
+                continue;
+
+            var gender = EntityGender.GetFromPIDAndRatio(pid, gr);
+            if (!criteria.IsGenderSatisfied(gender))
+                continue;
+
+            pk.PID = pid;
+            pk.Ability = ((XDRNG.Next2(seed) >> 16) & 1) == 0 ? pi.Ability1 : pi.Ability2;
+            criteria.SetRandomIVs(pk);
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// Tries to set a valid PID/IV for the requested criteria for a Colosseum starter (Umbreon and Espeon), preferring to match Trainer IDs.
+    /// </summary>
+    public static bool SetFromTrainerIDStarter(CK3 pk, EncounterCriteria criteria, PersonalInfo3 pi, ushort tid, ushort sid)
+    {
+        // * => TID, SID, fakepid*2, [IVs, ability, PID]
+        Span<uint> all = stackalloc uint[XDRNG.MaxCountSeedsPID];
+        var count = XDRNG.GetSeeds(all, (uint)tid << 16, (uint)sid << 16);
+        var seeds = all[..count];
+        foreach (ref var seed in seeds)
+        {
+            var s = XDRNG.Next7(seed);
+            uint pid = GetPIDStarterMale(ref s, pk.ID32);
+            if (pk.Species == (int)Species.Espeon) // After Umbreon
+            {
+                s = XDRNG.Next2(s);
+                pid = GetPIDStarterMale(ref s, pk.ID32);
+            }
+            if (criteria.IsSpecifiedNature() && (Nature)(pid % 25) != criteria.Nature)
+                continue;
+
+            var ivSeed = XDRNG.Next4(seed);
+            var iv1 = XDRNG.Next15(ref ivSeed);
+            var iv2 = XDRNG.Next15(ref ivSeed);
+
+            SetIVs(pk, iv1, iv2);
+            pk.PID = pid;
+            pk.Ability = ((XDRNG.Next2(seed) >> 16) & 1) == 0 ? pi.Ability1 : pi.Ability2;
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// Tries to set a valid PID/IV for the requested criteria for the XD starter (Eevee), preferring to match Trainer IDs.
+    /// </summary>
+    public static bool SetFromTrainerIDStarter(XK3 pk, EncounterCriteria criteria, PersonalInfo3 pi, ushort tid, ushort sid)
+    {
+        // * => TID, SID, fakepid*2, [IVs, ability, PID]
+        Span<uint> all = stackalloc uint[XDRNG.MaxCountSeedsPID];
+        var count = XDRNG.GetSeeds(all, (uint)tid << 16, (uint)sid << 16);
+        var seeds = all[..count];
+        foreach (ref var seed in seeds)
+        {
+            var s = XDRNG.Next7(seed);
+            uint pid = GetPID(s);
+            if (criteria.IsSpecifiedNature() && (Nature)(pid % 25) != criteria.Nature)
+                continue;
+
+            var ivSeed = XDRNG.Next4(seed);
+            var iv1 = XDRNG.Next15(ref ivSeed);
+            var iv2 = XDRNG.Next15(ref ivSeed);
+
+            SetIVs(pk, iv1, iv2);
+            pk.PID = pid;
+            pk.Ability = ((XDRNG.Next2(seed) >> 16) & 1) == 0 ? pi.Ability1 : pi.Ability2;
+            return true;
+        }
+
+        return false;
+    }
+
+    private static uint GetPID(uint seed)
+    {
+        var a = XDRNG.Next16(ref seed);
+        var b = XDRNG.Next16(ref seed);
+        return GetPIDRegular(a, b);
+    }
+
+    private static uint GetPID(G3PKM pk, uint seed, bool noShiny)
+    {
+        while (true)
+        {
+            var a = XDRNG.Next16(ref seed);
+            var b = XDRNG.Next16(ref seed);
+            var pid = GetPIDRegular(a, b);
+            if (!noShiny || !ShinyUtil.GetIsShiny(pk.ID32, pid))
+                return pid;
+        }
+    }
+
+    private static uint GetPIDStarterMale(ref uint seed, uint id32)
+    {
+        const byte ratio = 0x1F; // 12.5% F (can't be female)
+        while (true)
+        {
+            var a = XDRNG.Next16(ref seed);
+            var b = XDRNG.Next16(ref seed);
+            var pid = GetPIDRegular(a, b);
+            if ((pid & 0xFF) >= ratio && !ShinyUtil.GetIsShiny(id32, pid))
+                return pid;
+        }
+    }
+
+    private static uint GetPIDRegular(uint a, uint b) => a << 16 | b;
+
+    private static (uint iv1, uint iv2) GetCombinedIVs(EncounterCriteria criteria)
+    {
+        uint iv1 = (uint)criteria.IV_HP | (uint)criteria.IV_ATK << 5 | (uint)criteria.IV_DEF << 10;
+        uint iv2 = (uint)criteria.IV_SPE | (uint)criteria.IV_SPA << 5 | (uint)criteria.IV_SPD << 10;
+        return (iv1, iv2);
+    }
+
+    private static void SetIVs(G3PKM pk, uint iv1, uint iv2)
+    {
+        Span<int> ivs = stackalloc int[6];
+        MethodFinder.GetIVsInt32(ivs, iv1, iv2);
+        pk.SetIVs(ivs);
+    }
+}