/* * Copyright 2016 Nu-book Inc. * Copyright 2016 ZXing authors */ // SPDX-License-Identifier: Apache-2.0 #pragma once #include "BitMatrix.h" #include #include namespace ZXing::QRCode { /** *

Encapsulates data masks for the data bits in a QR and micro QR code, per ISO 18004:2006 6.8.

* *

Note that the diagram in section 6.8.1 is misleading since it indicates that i is column position * and j is row position. In fact, as the text says, i is row position and j is column position.

*/ inline bool GetDataMaskBit(int maskIndex, int x, int y, bool isMicro = false) { if (isMicro) { if (maskIndex < 0 || maskIndex >= 4) throw std::invalid_argument("QRCode maskIndex out of range"); maskIndex = std::array{1, 4, 6, 7}[maskIndex]; // map from MQR to QR indices } switch (maskIndex) { case 0: return (y + x) % 2 == 0; case 1: return y % 2 == 0; case 2: return x % 3 == 0; case 3: return (y + x) % 3 == 0; case 4: return ((y / 2) + (x / 3)) % 2 == 0; case 5: return (y * x) % 6 == 0; case 6: return ((y * x) % 6) < 3; case 7: return (y + x + ((y * x) % 3)) % 2 == 0; } throw std::invalid_argument("QRCode maskIndex out of range"); } inline bool GetMaskedBit(const BitMatrix& bits, int x, int y, int maskIndex, bool isMicro = false) { return GetDataMaskBit(maskIndex, x, y, isMicro) != bits.get(x, y); } } // namespace ZXing::QRCode