• Bitboard infrastructure with a staged move generator
  • Alpha-Beta search with null move, PVS, razoring and futility pruning
  • Quiescence search with SEE and delta pruning
  • Other features: separate PV hashtable, mate distance pruning, enhanced transposition cutoff
  • Evaluation function centered around piece activity
  • Opening book (over 96.000 entries)

UCI options

First there are self-explanatory options for setting hash size, then the following:

Hashfull which hashtable, if any, should report how much of it is filled
Own book path a path to an opening book in *.gob format
Buffer sets the interval in which information is sent to the GUI
MultiPV number of analysis lines displayed in multiPV node
TimeBuffer value determining how much time in miliseconds Glass should keep in reserve in order to avoid a loss on time caused by a lag in communication with GUI
Aggression - moved to personality files this weight shows how important it is for Glass to attack opponent's king; default is 100, but slightly higher values have also proven interesting.
Caution - moved to personality files this weight shows how much Glass cares for its own king being under attack; default is 100, but slightly higher values have also proven interesting.
Freedom - moved to personality files weight assigned by Glass' to its own piece mobility; default is 100.
Restraint - moved to personality files weight of enemy piece mobility; default is 120, which means that our engine pays more attention to restricting opponent's movements than to its own activity. Tests have shown that after rewriting king safety routine (and generally increasing its impact on evaluation) this asymmetry works as a counter-balance, preventing Glass from giving the enemy to much freedom while attacking.
Passers - moved to personality files weight of passed pawns evaluation, default is 100
Pawn structure - moved to personality files weight of weak pawns evaluation, default is 100. Whereas it may seem that Glass is a bit careless in that departament, our tests didn't show any benefits of raising this value.
Contempt - moved to personality files middlegame draw value, used to assign score to draws by repetition etc. Higher value means that Glass will try to keep the ball rolling even if it does not like its position. Default is 10, but please note that in the endgame this value will be replaced by 0.

Please note that the Analyze option should be set when analyzing a position from both sides (otherwise Hashentries won’t be used), and disabled while playing (to use asymmetric eval)

Since version 1.0 Glass supports also searchmoves options -> eg: “go searchmoves e2e4 d2d4” to only search the two mentioned moves in the startposition