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'''[[Main Page|Home]] * [[Board Representation]] * [[Bitboards]] * [[Sliding Piece Attacks]] * Hyperbola Quintessence'''
[[FILE:SamuelBakReflexion.jpg|border|right|thumb|[[Arts#:Category:Samuel Bak|Samuel Bak]] - Reflexion, 1990 <ref>[https://www.puckergallery.com/artists/#/samuel-bak/ Samuel Bak - represented by Pucker Gallery since 1969]</ref> ]]
'''Hyperbola Quintessence''' applies the [[Subtracting a Rook from a Blocking Piece|o^(o-2r)-trick]] also for vertical or diagonal [[On an empty Board#NegativeRays|negative Rays]] - by reversing the bit-order of up to one bit per rank or [[Byte|byte]] with a [[Flipping Mirroring and Rotating#FlipVertically|vertical flip]] aka [[x86-64]] [[x86-64#gpinstructions|bswap]] <ref>[http://msdn.microsoft.com/en-us/library/a3140177.aspx _byteswap_uint64] Visual C++ Developer Center - Run-Time Library Reference</ref> . It is somehow a resurrection of the [[Reverse Bitboards|reverse bitboards]] idea of [[Ryan Mack|Ryan Mack's]] ''Hyperbola Project'' on the fly, and was created by [[Gerd Isenberg]]. Improvements by [[Aleks Peshkov]] <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=140314 Re: BitBoard Tests Magic v Non-Rotated 32 Bits v 64 Bits] by [[Aleks Peshkov]], [[CCC]], August 25, [[Timeline#2007|2007]]</ref> made it applicable and competitive.
