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Rangi
996469ee28
Some test cases need CRLF line endings checked out even on Unix. Also some source files had inadvertently contained CR bytes.
24 lines
724 B
C++
24 lines
724 B
C++
// SPDX-License-Identifier: MIT
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#ifndef RGBDS_GFX_FLIP_HPP
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#define RGBDS_GFX_FLIP_HPP
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#include <array>
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#include <stdint.h>
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// Flipping tends to happen fairly often, so take a bite out of dcache to speed it up
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static std::array<uint16_t, 256> flipTable = ([]() constexpr {
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std::array<uint16_t, 256> table{};
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for (uint16_t i = 0; i < table.size(); ++i) {
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// To flip all the bits, we'll flip both nibbles, then each nibble half, etc.
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uint16_t byte = i;
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byte = (byte & 0b0000'1111) << 4 | (byte & 0b1111'0000) >> 4;
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byte = (byte & 0b0011'0011) << 2 | (byte & 0b1100'1100) >> 2;
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byte = (byte & 0b0101'0101) << 1 | (byte & 0b1010'1010) >> 1;
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table[i] = byte;
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}
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return table;
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})();
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#endif // RGBDS_GFX_FLIP_HPP
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