Field::Encount::PokeSet::EncountProbCalc

unsigned int __fastcall Field::Encount::PokeSet::EncountProbCalc(int a1, unsigned int EncounterProbability, Field::EventPokemonRideTool *a3)
{
  int v3; // r12@1
  int v4; // r12@5
  bool v5; // zf@5
  signed int v6; // r4@10
  unsigned int v7; // r5@12
  unsigned int result; // r0@18

  v3 = *(a1 + 528);
  if ( v3 & 1 )                                 // 100% increase (double down) from arena trap etc
  {
    EncounterProbability *= 2;
  }
  else if ( v3 & 2 )                            // 50% decrease
  {
    EncounterProbability >>= 1;
  }
  else
  {
    v4 = *(a1 + 502);
    v5 = v4 == 224;                             // cleanse tag
    if ( v4 != 224 )
      v5 = v4 == 320;                           // pure incense
    if ( v5 )
      EncounterProbability = 2 * EncounterProbability / 3;
  }
  v6 = 100;
  if ( *(a1 + 524) & 0x20 )                     // 1/4
    EncounterProbability >>= 2;
  v7 = EncounterProbability;
  switch ( Field::EventPokemonRideTool::GetPokemonRideOnID(a3, 0, a3) )
  {
    case 0:
      v6 = 50;
      break;
    case 1:
      v6 = 15;
      break;
    case 2:
      v6 = 55;
      break;
    case 3:
      v6 = 20;
      break;
    default:
      break;
    case 6:
      v6 = 65;
      break;
  }
  result = v7 * v6 / 100;
  if ( result > 100 )
    result = 100;
  return result;
}