forked from 0ad/0ad
38 lines
1013 B
C++
38 lines
1013 B
C++
/* Copyright (C) 2009 Wildfire Games.
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* This file is part of 0 A.D.
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*
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* 0 A.D. is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 2 of the License, or
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* (at your option) any later version.
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*
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* 0 A.D. is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with 0 A.D. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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* bit-twiddling.
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*/
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#include "precompiled.h"
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#include "bits.h"
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static inline u32 get_float_bits(const float x)
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{
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u32 ret;
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memcpy(&ret, &x, 4);
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return ret;
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}
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int floor_log2(const float x)
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{
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const u32 i = get_float_bits(x);
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const u32 biased_exp = (i >> 23) & 0xFF;
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return (int)biased_exp - 127;
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}
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