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+//
+//  Tables.swift
+//  Sage
+//
+//  Copyright 2016-2017 Nikolai Vazquez
+//  Modified by SuperGeroy
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+//
+
+/// Returns the pawn attack table for `color`.
+internal func _pawnAttackTable(for color: Color) -> [Bitboard] {
+    if color.isWhite {
+        return _whitePawnAttackTable
+    } else {
+        return _blackPawnAttackTable
+    }
+}
+
+/// A lookup table of all white pawn attack bitboards.
+internal let _whitePawnAttackTable = Square.all.map { square in
+    return Bitboard(square: square)._pawnAttacks(for: ._white)
+}
+
+/// A lookup table of all black pawn attack bitboards.
+internal let _blackPawnAttackTable = Square.all.map { square in
+    return Bitboard(square: square)._pawnAttacks(for: ._black)
+}
+
+/// A lookup table of all king attack bitboards.
+internal let _kingAttackTable = Square.all.map { square in
+    return Bitboard(square: square)._kingAttacks()
+}
+
+/// A lookup table of all knight attack bitboards.
+internal let _knightAttackTable = Square.all.map { square in
+    return Bitboard(square: square)._knightAttacks()
+}
+
+/// Returns the squares between `start` and `end`.
+private func _between(_ start: Square, _ end: Square) -> Bitboard {
+    let start = UInt64(start.hashValue)
+    let end = UInt64(end.hashValue)
+    let max = UInt64.max
+    let a2a7: UInt64 = 0x0001010101010100
+    let b2g7: UInt64 = 0x0040201008040200
+    let h1b7: UInt64 = 0x0002040810204080
+
+    let between = (max << start) ^ (max << end)
+    let file = (end & 7) &- (start & 7)
+    let rank = ((end | 7) &- start) >> 3
+
+    var line = ((file & 7) &- 1) & a2a7
+    line += 2 &* (((rank & 7) &- 1) >> 58)
+    line += (((rank &- file) & 15) &- 1) & b2g7
+    line += (((rank &+ file) & 15) &- 1) & h1b7
+    line = line &* (between & (0 &- between))
+
+    return Bitboard(rawValue: line & between)
+}
+
+/// Returns the triangle index for `start` and `end`.
+internal func _triangleIndex(_ start: Square, _ end: Square) -> Int {
+    var a = start.hashValue
+    var b = end.hashValue
+    var d = a &- b
+    d &= d >> 31
+    b = b &+ d
+    a = a &- d
+    b = b &* (b ^ 127)
+    return (b >> 1) + a
+}
+
+/// A lookup table of squares between two squares.
+internal let _betweenTable: [Bitboard] = {
+    var table = [Bitboard](repeating: 0, count: 2080)
+    for start in Square.all {
+        for end in Square.all {
+            let index = _triangleIndex(start, end)
+            table[index] = _between(start, end)
+        }
+    }
+    return table
+}()
+
+/// A lookup table of lines for two squares.
+internal let _lineTable: [Bitboard] = {
+    var table = [Bitboard](repeating: 0, count: 2080)
+    for start in Square.all {
+        for end in Square.all {
+            let startBB = Bitboard(square: start)
+            let endBB = Bitboard(square: end)
+            let index = _triangleIndex(start, end)
+            let rookAttacks = startBB._rookAttacks()
+            let bishopAttacks = startBB._bishopAttacks()
+            if rookAttacks[end] {
+                table[index] = startBB | endBB | (rookAttacks & endBB._rookAttacks())
+            } else if bishopAttacks[end] {
+                table[index] = startBB | endBB | (bishopAttacks & endBB._bishopAttacks())
+            }
+        }
+    }
+    return table
+}()