KiCad PCB EDA Suite
3d_fastmath.cpp
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1 /*
2  * This program source code file is part of KiCad, a free EDA CAD application.
3  *
4  * Copyright (C) 2016 Mario Luzeiro <mrluzeiro@ua.pt>
5  * Copyright (C) 1992-2016 KiCad Developers, see AUTHORS.txt for contributors.
6  *
7  * This program is free software; you can redistribute it and/or
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24 
31 #include "3d_fastmath.h"
32 
33 
34 // Fast Float Random Numbers
35 // a small and fast implementation for random float numbers in the range [-1,1]
36 // References : Posted by dominik.ries[AT]gmail[DOT]com
37 // http://www.musicdsp.org/showone.php?id=273
38 
39 
40 // set the initial seed to whatever you like
41 static int s_randSeed = 1;
42 
43 // fast rand float, using full 32bit precision
44 // returns in the range [-1, 1] (not confirmed)
46 {
47  s_randSeed *= 16807;
48 
49  return (float)s_randSeed * 4.6566129e-010f;
50 }
51 
52 
53 // Fast rand, as described here:
54 // http://wiki.osdev.org/Random_Number_Generator
55 
56 static unsigned long int s_nextRandSeed = 1;
57 
58 int Fast_rand( void ) // RAND_MAX assumed to be 32767
59 {
60  s_nextRandSeed = s_nextRandSeed * 1103515245 + 12345;
61 
62  return (unsigned int)(s_nextRandSeed >> 16) & 0x7FFF;
63 }
64 
65 void Fast_srand( unsigned int seed )
66 {
67  s_nextRandSeed = seed;
68 }
void Fast_srand(unsigned int seed)
Definition: 3d_fastmath.cpp:65
static int s_randSeed
Definition: 3d_fastmath.cpp:41
Defines math related functions.
int Fast_rand(void)
Definition: 3d_fastmath.cpp:58
float Fast_RandFloat()
Definition: 3d_fastmath.cpp:45
static unsigned long int s_nextRandSeed
Definition: 3d_fastmath.cpp:56