💡📝H. G. Muller wrote on Wed, Jul 24, 2019 03:47 PM UTC:
Oops... It seems there has been a mixup of versions at some point. This code was added as a hack to do Peace Chess, where pieces can combine to 'embracing pairs' coexisting on the same square. The IDs for these combinations are generated here automatically. Piece Chess of course only has 6 basic piece types, so for that purpose having the pair codes start at 64 located them well beyond 'nType', with a large safety margin. But I should never have used that hacked version for replacing the script that powers the diagram in general, at least not without modification. There is no reason why the 64 could not be replaced by (say) 400, to not wreck any variants with fewer than 400 piece types. (Without this hack the limit was 512 piece types; the 512 bit is used to indicate piece virginity, the 1024 bit for piece color.)
Oops... It seems there has been a mixup of versions at some point. This code was added as a hack to do Peace Chess, where pieces can combine to 'embracing pairs' coexisting on the same square. The IDs for these combinations are generated here automatically. Piece Chess of course only has 6 basic piece types, so for that purpose having the pair codes start at 64 located them well beyond 'nType', with a large safety margin. But I should never have used that hacked version for replacing the script that powers the diagram in general, at least not without modification. There is no reason why the 64 could not be replaced by (say) 400, to not wreck any variants with fewer than 400 piece types. (Without this hack the limit was 512 piece types; the 512 bit is used to indicate piece virginity, the 1024 bit for piece color.)
Thanks for spotting this; I will fix it soon.