Author: Dan Honeycutt
Date: 09:03:13 08/31/04
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On August 31, 2004 at 04:50:27, Richard Pijl wrote: > >I'm feeding both pinned and pinning pieces as a bitboard to my SEE routine. >Whenever a pinning piece enters the exchange (easy check with bitboards) I'm >examining whether the pinning piece releases a pin, or that another piece >becomes the pinning piece. >Of course, there are positions where this misevaluates as well, but generally it >gives a better value. >The penalty for taking pins into account in the SEE is not that big when you're >already have those bitmasks available for evaluation purposes. >I only use the pin-aware SEE in Qsearch as I don't have the pinned/pinning >bitmasks available in inner nodes (something to try I guess, e.g. to use the >pin/pinning data also in moveordering). > >Richard. Thanks Richard for the good ideas. I'm using my move generation pin routine which produces a bitmap of pinned pieces and for each one the squares where they can go - a ray from the friendly king to and including the pinning piece. So right now I don't have the pinning piece but I can get it pretty cheap. I'll tinker with this. Having pins for both sides available at all times opens the door for me to add pins to my evaluation for no extra cost. Do you just add a bonus per pin or do you try to make some determination of the worth of the pin? Doing pin-aware SEE only in QSearch makes a lot of sense. I hadn't thought of that. Thanks again. Dan H.
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