mirror of https://gitlab.com/nakst/essence
58 lines
1.1 KiB
C
58 lines
1.1 KiB
C
//
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// Copyright(C) 1993-1996 Id Software, Inc.
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// Copyright(C) 2005-2014 Simon Howard
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//
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License
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// as published by the Free Software Foundation; either version 2
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// of the License, or (at your option) any later version.
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//
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// This program 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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// DESCRIPTION:
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// Fixed point implementation.
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//
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#include "essence/include.h"
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#include "doomtype.h"
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#include "i_system.h"
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#include "m_fixed.h"
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// Fixme. __USE_C_FIXED__ or something.
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fixed_t
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FixedMul
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( fixed_t a,
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fixed_t b )
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{
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return ((int64_t) a * (int64_t) b) >> FRACBITS;
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}
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//
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// FixedDiv, C version.
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//
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fixed_t FixedDiv(fixed_t a, fixed_t b)
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{
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if ((ES_abs(a) >> 14) >= ES_abs(b))
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{
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return (a^b) < 0 ? INT_MIN : INT_MAX;
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}
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else
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{
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int64_t result;
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result = ((int64_t) a << 16) / b;
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return (fixed_t) result;
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}
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}
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