kicad/3d-viewer/3d_fastmath.cpp

69 lines
2.0 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2016 Mario Luzeiro <mrluzeiro@ua.pt>
* Copyright (C) 1992-2016 KiCad Developers, see AUTHORS.txt for contributors.
*
* 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, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
/**
* @file 3d_fastmath.cpp
* @brief
*/
#include "3d_fastmath.h"
// Fast Float Random Numbers
// a small and fast implementation for random float numbers in the range [-1,1]
// References : Posted by dominik.ries[AT]gmail[DOT]com
// http://www.musicdsp.org/showone.php?id=273
// set the initial seed to whatever you like
static int s_randSeed = 1;
// fast rand float, using full 32bit precision
// returns in the range [-1, 1] (not confirmed)
float Fast_RandFloat()
{
s_randSeed *= 16807;
return (float)s_randSeed * 4.6566129e-010f;
}
// Fast rand, as described here:
// http://wiki.osdev.org/Random_Number_Generator
static unsigned long int s_nextRandSeed = 1;
int Fast_rand( void ) // RAND_MAX assumed to be 32767
{
s_nextRandSeed = s_nextRandSeed * 1103515245 + 12345;
return (unsigned int)(s_nextRandSeed >> 16) & 0x7FFF;
}
void Fast_srand( unsigned int seed )
{
s_nextRandSeed = seed;
}