Quick Questions / Quick Answers

I wrote all of the code for this myself not that long ago.

Normal calculation (a similar calculation is used when calculating approach):

Code:

int CvDiplomacyAI::GetReligionScore(PlayerTypes ePlayer)
{
   int iOpinionWeight = 0;
   if (GC.getGame().isOption(GAMEOPTION_NO_RELIGION)) return 0;
   if (IsVassal(ePlayer)) return 0; // Don't double dip

   ReligionTypes eOurStateReligion = GetPlayer()->GetReligions()->GetCurrentReligion(false);
   ReligionTypes eOurMajorityReligion = GetPlayer()->GetReligions()->GetReligionInMostCities();
   ReligionTypes eTheirStateReligion = GET_PLAYER(ePlayer).GetReligions()->GetCurrentReligion(false);
   ReligionTypes eTheirMajorityReligion = GET_PLAYER(ePlayer).GetReligions()->GetReligionInMostCities();

   int iFlavorReligion = m_pPlayer->GetFlavorManager()->GetPersonalityFlavorForDiplomacy((FlavorTypes)GC.getInfoTypeForString("FLAVOR_RELIGION"));
   int iEraMod = GC.getEraInfo(GC.getGame().getCurrentEra())->getDiploEmphasisReligion();

   // Weight increases or decreases based on flavors
   if (iFlavorReligion < 5)
   {
       iEraMod = max(0, iEraMod - 1);
   }
   else if (iFlavorReligion > 7)
   {
       iEraMod++;
   }

#if defined(MOD_BALANCE_CORE)
   iEraMod += (MOD_BALANCE_CORE && GetPlayer()->GetPlayerTraits()->IsReligious()) ? 1 : 0;
#endif

   // We didn't found or conquer, but have a majority religion
   if (eOurStateReligion == NO_RELIGION && eOurMajorityReligion != NO_RELIGION)
   {
       if (GetNegativeReligiousConversionPoints(ePlayer) <= 0 && !IsHolyCityCapturedBy(ePlayer))
       {
           if (eOurMajorityReligion == eTheirStateReligion)
           {
               // They must have at least one of their own cities following their state religion to get a bonus
               if (GC.getGame().GetGameReligions()->GetNumDomesticCitiesFollowing(eTheirStateReligion, ePlayer) > 0)
               {
                   iOpinionWeight += /*-4*/ GC.getOPINION_WEIGHT_ADOPTING_HIS_RELIGION() * iEraMod;

                   // If it's the World Religion and they're its controller, support them since we get extra League votes from it
                   if (GC.getGame().GetGameLeagues()->GetReligionSpreadStrengthModifier(ePlayer, eTheirStateReligion) > 0)
                   {
                       iOpinionWeight *= /*150*/ GC.getOPINION_WEIGHT_WORLD_RELIGION_MODIFIER();
                       iOpinionWeight /= 100;
                   }
               }
           }
           // Same majority religions?
           else if (eOurMajorityReligion == eTheirMajorityReligion)
           {
               iOpinionWeight += /*-2*/ GC.getOPINION_WEIGHT_SAME_MAJORITY_RELIGIONS() * iEraMod;
           }
       }
       // Different majority religions?
       if (eOurMajorityReligion != eTheirStateReligion && eOurMajorityReligion != eTheirMajorityReligion && eTheirMajorityReligion != NO_RELIGION)
       {
           iOpinionWeight += /*2*/ GC.getOPINION_WEIGHT_DIFFERENT_MAJORITY_RELIGIONS() * iEraMod;
       }
   }
   // We founded or conquered
   else if (eOurStateReligion != NO_RELIGION)
   {
       // Do they also have a state religion? We don't like that!
       if (eTheirStateReligion != NO_RELIGION && GC.getGame().GetGameReligions()->GetNumDomesticCitiesFollowing(eTheirStateReligion, ePlayer) > 0)
       {
           iOpinionWeight += /*5*/ GC.getOPINION_WEIGHT_DIFFERENT_STATE_RELIGIONS() * iEraMod;

           // If it's the World Religion and they control its Holy City, we should work against them
           if (GC.getGame().GetGameLeagues()->GetReligionSpreadStrengthModifier(ePlayer, eTheirStateReligion) > 0)
           {
               iOpinionWeight *= /*150*/ GC.getOPINION_WEIGHT_WORLD_RELIGION_MODIFIER();
               iOpinionWeight /= 100;
           }
       }
       // No? Well, do they have a majority religion?
       else if (eTheirMajorityReligion != NO_RELIGION)
       {
           // Ours?
           if (eTheirMajorityReligion == eOurStateReligion)
           {
               iOpinionWeight += /*-8*/ GC.getOPINION_WEIGHT_ADOPTING_MY_RELIGION() * iEraMod;

               // If it's the World Religion and we control its Holy City, we should work together
               if (GC.getGame().GetGameLeagues()->GetReligionSpreadStrengthModifier(GetPlayer()->GetID(), eOurStateReligion) > 0)
               {
                   iOpinionWeight *= /*150*/ GC.getOPINION_WEIGHT_WORLD_RELIGION_MODIFIER();
                   iOpinionWeight /= 100;
               }
           }
           // Someone else's?
           else
           {
               const CvReligion* pReligion = GC.getGame().GetGameReligions()->GetReligion(eTheirMajorityReligion, NO_PLAYER);

               // If the religion's founder is our teammate, don't apply a penalty if that teammate is still alive.
               if (IsTeammate((PlayerTypes)pReligion->m_eFounder) && GET_PLAYER((PlayerTypes)pReligion->m_eFounder).getNumCities() > 0)
                   return 0;

               // If the religion's founder is THEIR teammate, treat it like a state religion.
               if (GET_PLAYER(ePlayer).GetDiplomacyAI()->IsTeammate((PlayerTypes)pReligion->m_eFounder) && GET_PLAYER((PlayerTypes)pReligion->m_eFounder).getNumCities() > 0)
               {
                   iOpinionWeight += /*5*/ GC.getOPINION_WEIGHT_DIFFERENT_STATE_RELIGIONS() * iEraMod;

                   // If it's the World Religion and their teammate controls its Holy City, we should work against them
                   if (GC.getGame().GetGameLeagues()->GetReligionSpreadStrengthModifier((PlayerTypes)pReligion->m_eFounder, eTheirMajorityReligion) > 0)
                   {
                       iOpinionWeight *= /*150*/ GC.getOPINION_WEIGHT_WORLD_RELIGION_MODIFIER();
                       iOpinionWeight /= 100;
                   }
               }
               // Otherwise, apply a penalty for different majority religions.
               else
               {
                   iOpinionWeight += /*2*/ GC.getOPINION_WEIGHT_DIFFERENT_MAJORITY_RELIGIONS() * iEraMod;
               }
           }
       }
   }

   if (iOpinionWeight > 0 && IsIgnoreReligionDifferences(ePlayer))
       return 0;

   return iOpinionWeight;
}

Vassal calculation:

Code:

int CvDiplomacyAI::GetVassalReligionScore(PlayerTypes ePlayer) const
{
   if (GC.getGame().isOption(GAMEOPTION_NO_RELIGION)) return 0;
   if (!IsVassal(ePlayer)) return 0;

   int iOpinionWeight = 0;

   ReligionTypes eVassalStateReligion = GetPlayer()->GetReligions()->GetCurrentReligion(false);
   ReligionTypes eVassalMajorityReligion = GetPlayer()->GetReligions()->GetReligionInMostCities();
   ReligionTypes eMasterStateReligion = GET_PLAYER(ePlayer).GetReligions()->GetCurrentReligion(false);
   ReligionTypes eMasterMajorityReligion = GET_PLAYER(ePlayer).GetReligions()->GetReligionInMostCities();

   // No vassal religion - don't care
   if (eVassalStateReligion == NO_RELIGION && eVassalMajorityReligion == NO_RELIGION)
       return 0;

   // Vassal did not found or conquer
   if (eVassalStateReligion == NO_RELIGION)
   {
       // Master founded, and we have their religion
       if (eMasterStateReligion != NO_RELIGION && eMasterStateReligion == eVassalMajorityReligion && GC.getGame().GetGameReligions()->GetNumDomesticCitiesFollowing(eMasterStateReligion, ePlayer) > 0)
       {
           iOpinionWeight += -20;
       }
       // Same majority religions
       else if (eMasterMajorityReligion != NO_RELIGION && eMasterMajorityReligion == eVassalMajorityReligion)
       {
           iOpinionWeight += -10;
       }
   }
   // Vassal did found or conquer
   else
   {
       // Master also founded or conquered
       if (eMasterStateReligion != NO_RELIGION && GC.getGame().GetGameReligions()->GetNumDomesticCitiesFollowing(eMasterStateReligion, ePlayer) > 0)
       {
           // ... and it's our majority religion
           if (eMasterStateReligion == eVassalMajorityReligion)
           {
               iOpinionWeight += 25;
           }
           // ... and they've converted some of our cities
           else if (GC.getGame().GetGameReligions()->GetNumDomesticCitiesFollowing(eMasterStateReligion, GetPlayer()->GetID()) > 0)
           {
               iOpinionWeight += 10;
           }
       }
       // Master did not found or conquer, but does have a majority religion - ours
       else if (eMasterMajorityReligion != NO_RELIGION && eMasterMajorityReligion == eVassalStateReligion)
       {
           iOpinionWeight += -40;
       }
   }
  
   if (IsVoluntaryVassalage(ePlayer))
   {
       iOpinionWeight *= GC.getOPINION_WEIGHT_VASSALAGE_VOLUNTARY_VASSAL_MOD();
       iOpinionWeight /= 100;
   }

   // No opinion bonuses if the Holy City was captured and we don't have it back yet
   if (iOpinionWeight < 0 && GetPlayer()->IsHasLostHolyCity() && IsPlayerCapturedHolyCity(ePlayer))
       return 0;

   // No opinion penalties if ignoring religious differences
   if (iOpinionWeight > 0 && GetPlayer()->GetDiplomacyAI()->IsIgnoreReligionDifferences(ePlayer))
       return 0;

   return iOpinionWeight;
}

Whether to ignore religious differences:

Code:

/// Should we ignore religious differences with ePlayer?
bool CvDiplomacyAI::IsIgnoreReligionDifferences(PlayerTypes ePlayer) const
{
   if (IsTeammate(ePlayer) || IsMaster(ePlayer))
       return true;

   if (GetNegativeReligiousConversionPoints(ePlayer) > 0)
       return false;

   if (IsAtWar(ePlayer) || IsCapitalCapturedBy(ePlayer) || IsHolyCityCapturedBy(ePlayer) || IsTeamUntrustworthy(GET_PLAYER(ePlayer).getTeam()))
       return false;

   if (IsPlayerLiberatedCapital(ePlayer) || WasResurrectedBy(ePlayer) || GET_TEAM(GetTeam()).GetLiberatedByTeam() == GET_PLAYER(ePlayer).getTeam() || GetDoFType(ePlayer) == DOF_TYPE_BATTLE_BROTHERS)
       return true;

   return false;
}

Great Prophets are born in the city with the greatest Faith output, not the capital - so it'd be whatever religion that city is, if I'm not mistaken.