ZoneBuilder/Source/Plugins/vpo_dll/m_fixed.cc

66 lines
1.5 KiB
C++

// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
// DESCRIPTION:
// Fixed point implementation.
//
//-----------------------------------------------------------------------------
#include "vpo_local.h"
namespace vpo
{
// Fixme. __USE_C_FIXED__ or something.
fixed_t
FixedMul
( fixed_t a,
fixed_t b )
{
return ((int64_t) a * (int64_t) b) >> FRACBITS;
}
//
// FixedDiv, C version.
//
fixed_t FixedDiv(fixed_t a, fixed_t b)
{
if ((abs(a) >> 14) >= abs(b))
{
return (a^b) < 0 ? INT_MIN : INT_MAX;
}
else
{
int64_t result;
result = ((int64_t) a << 16) / b;
return (fixed_t) result;
}
}
} // namespace vpo