#367 Large .bin opening books are slow

[Sandy]

Hi, just wanted to report that large Polyglot opening books are very slow to load/display available moves.

I have a .bin opening book of around 1.5GB and even when just making moves on the board without any engines running, it takes a long time to load new moves. Like, if I move the white pawn to D4, the opening tree window will take at least a few seconds before the possible responses for black are displayed.

Smaller .bin books, like a few MBs in size display moves instantly.

No issues with large CTG books. I have a 2GB .ctg book and moves are displayed instantly in the opening tree window and after every move on the board.

I don't have any really large ABK books but I have found no issues when using a ~80mb .abk book.

Thank you for this awesome program. Your work is very much appreciated!

Sandy