Thank you very much for this tip.mvanthoor wrote: ↑Wed Sep 30, 2020 10:45 pmHave you ever thought about adding this? Your engine is already at +/- 2500 Elo without this knowledge. Stuff like passed pawn evaluation is known to add over 100 Elo in some engines. According to MadChess by Eric Madsen:
+ 119 for passed pawns.
+ 63 for king safety.
1) Passed Pawns:
OliThink knows about "passed pawns", because it's a part of mobility. Passed Pawns have much more squares to move before being eaten/blocked by an enemy pawn.
2) King safety:
True, this is one of OliThink's weaknesses, because this is not explicitly implemented at all.
Implicitly, though, there are some mobility evaluation which help the poor King a little:
a) The King tends to go to center of board dependent on how many enemy officers are on the board. With many pieces on board this is negative, so he should stay in the corner.
b) The mobility evaluation considers the fact, that attacking big enemy pieces (King, Queen, etc..) do not actually reduce the mobility of minor pieces, because they "have to go out of the way".
Of course, there is some implicit chess knowledge "hidden" in the mobility evaluation.