R3/IPPOLIT/Houdini and pawn "anti-mobility"

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BB+
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R3/IPPOLIT/Houdini and pawn "anti-mobility"

Post by BB+ » Mon Jan 31, 2011 3:55 am

From Jury Osipov:
About copying, rewriting of code and so on. In eval-function of Ivanhoe we can find:

Code: Select all

  U = (POSITION->OccupiedBW >> 8) & wBitboardP;
  while (U)
    {
      b = BSF (U);
      MobValue -= PawnAntiMobility;
      BitClear (b, U);
    }
Robert Houdart replace this at:

Code: Select all

  U = (POSITION->OccupiedBW >> 8) & wBitboardP;
  MobValue -= popcnt(U) * PawnAntiMobility;
Is it plagiarism?
No, I'd guess it's the IPPOLIT/IvanHoe crew failing to note this "obvious" improvement (multiplication rather than repeated addition) once they ditched the Rybka 3 method, where "PawnAntiMobility" can depend on the square in question (R3 also has some pawn mobility bonuses for pawns on the opposite side of the board of the opposing King).

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