38 lines
1.1 KiB
C++
38 lines
1.1 KiB
C++
// Copyright (C) 2020 Jérôme Leclercq
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// This file is part of the "Nazara Engine - Graphics module"
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// For conditions of distribution and use, see copyright notice in Config.hpp
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#include <Nazara/Graphics/Algorithm.hpp>
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#include <cmath>
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#include <cstring>
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#include <limits>
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#include <Nazara/Graphics/Debug.hpp>
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namespace Nz
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{
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inline UInt32 DistanceAsSortKey(float distance)
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{
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#if defined(arm) && \
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((defined(__MAVERICK__) && defined(NAZARA_BIG_ENDIAN)) || \
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(!defined(__SOFTFP__) && !defined(__VFP_FP__) && !defined(__MAVERICK__)))
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#error The following code relies on native-endian IEEE-754 representation, which your platform does not guarantee
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#endif
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static_assert(sizeof(float) == sizeof(UInt32));
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static_assert(std::numeric_limits<float>::is_iec559);
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if (std::isnan(distance))
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return std::numeric_limits<UInt32>::max();
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if (std::isinf(distance))
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return 0;
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UInt32 distanceInt;
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std::memcpy(&distanceInt, &distance, sizeof(UInt32));
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return ~distanceInt; //< Reverse distance to have back to front
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}
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}
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#include <Nazara/Graphics/DebugOff.hpp>
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