The definition of an obvious move is that all of the following conditions are true:
•
the shallow sorting pre-search of 3 plies depth shows a score drop of at least 2
pawns between the best and second best move.
•
the best move has been part of the principal variation in the previous turn, or the
result is within a
±
0.5 pawn window of the evaluation from the turn before. If neither
of these two pieces of information is available, quick replies will not be triggered by
an obvious move. This may happen e.g. right after the end of the opening book,
after taking back moves or after switching sides.
The
±
0.5 pawn window covers two aspects:
•
If the CT800 seems to be winning a piece out of nowhere, the CT800 will assume
that a sacrifice may be going on, and that needs serious calculation. That is why the
CT800 will not capture quickly if the opponent simply loses a piece by neglect.
•
If the seemingly obvious move still makes the CT800 stand much worse than
expected from the previous turn, then maybe the CT800 had already seen
something better, e.g. a mating attack.
Independently from forced or obvious moves, the CT800 also takes a look at how much
thinking time it has left for its move. If it has already used up more than 55% of the
allocated move time when starting the next search depth iteration, it will drop the next
depth iteration because it would not be able to complete it anyway.
3.2.3 Status Information
Towards the upper right corner of the display, there can be additional notifiers when the
CT800 announces its move:
•
“b”
: The CT800 took this move from its opening book.
•
“+”
: The CT800 thinks it is up by at least 0.5 pawns.
•
“-”
: The CT800 thinks it is down by at least 0.5 pawns:
•
“++”
: The CT800 thinks it is up by at least 3.0 pawns, which is a decisive
advantage.
•
“--”
: The CT800 thinks it is down by at least 3.0 pawns, so it is likely to loose the
game.
•
“+m” : The CT800 sees a forced mate and will win.
•
“-m”
: The CT800 sees that it can be mated.
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